XLMG3422R050RQZT [TI]

具有集成驱动器、保护和温度报告功能的 600V 50mΩ GaN FET | RQZ | 54 | -40 to 150;
XLMG3422R050RQZT
型号: XLMG3422R050RQZT
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

具有集成驱动器、保护和温度报告功能的 600V 50mΩ GaN FET | RQZ | 54 | -40 to 150

驱动 驱动器
文件: 总49页 (文件大小:2306K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
LMG3422R050, LMG3425R050  
ZHCSNN4B OCTOBER 2020 REVISED MAY 2022  
LMG342xR050 600V 50mΩ 具有集成驱动器、保护和温度报告功能GaN FET  
1 特性  
3 说明  
LMG342xR050 GaN FET 具有集成式驱动器和保护功  
可让设计人员在电力电子系统中实现更高水平的功  
率密度和效率。  
• 符合面向硬开关拓扑JEDEC JEP180 标准  
• 带集成栅极驱动器600-V GaN-on-Si FET  
– 集成高精度栅极偏置电压  
200V/ns CMTI  
3.6MHz 开关频率  
20V/ns 150V/ns 压摆率用于优化开关性能  
和缓EMI  
LMG342xR050 集成了一个硅驱动器可实现高达 150  
V/ns 的开关速度。与分立式硅栅极驱动器相比TI 的  
集成式精密栅极偏置可实现更高的开关 SOA。这种集  
成特性与 TI 的低电感封装技术相结合可在硬开关电  
源拓扑中提供干净的开关和超小的振铃。可调栅极驱动  
强度允许将压摆率控制在 20 V/ns 150 V/ns 之间,  
这可用于主动控制 EMI 优化开关性能。  
LMG3425R050 包含理想二极管模式该模式通过启  
用自适应死区时间控制功能来降低第三象限损耗。  
7.5V 18V 电源下工作  
• 强大的保护  
– 响应时间少100 ns 的逐周期过流和锁存短路  
保护  
– 硬开关时可承720V 浪涌  
– 针对内部过热UVLO 监控的自我保护  
• 高级电源管理  
高级电源管理功能包括数字温度报告和故障检测。  
GaN FET 的温度通过可变占空比 PWM 输出进行报  
这可简化器件加载管理。报告的故障包括过热、过  
UVLO 监控。  
– 数字温PWM 输出  
– 理想二极管模式可减LMG3425R050 中的第  
三象限损耗  
器件信息  
(1)  
2 应用  
封装尺寸标称值)  
器件型号  
LMG3422R050  
LMG3425R050  
• 高密度工业电源  
• 光伏逆变器和工业电机驱动器  
• 不间断电源  
商用网络和服务PSU  
商用电信整流器  
VQFN (54)  
12.00mm x 12.00mm  
(1) 如需了解所有可用封装请参阅数据表末尾的可订购产品附  
录。  
DRAIN  
Direct-Drive  
Slew  
GaN  
Rate  
SOURCE  
RDRV  
IN  
VDD  
VNEG  
LDO,  
BB  
OCP, SCP,  
OTP, UVLO  
Current  
LDO5V  
TEMP  
FAULT  
OC  
SOURCE  
简化版方框图  
100 V/ns 时的开关性能  
本文档旨在为方便起见提供有TI 产品中文版本的信息以确认产品的概要。有关适用的官方英文版本的最新信息请访问  
www.ti.com其内容始终优先。TI 不保证翻译的准确性和有效性。在实际设计之前请务必参考最新版本的英文版本。  
English Data Sheet: SNOSDA8  
 
 
 
 
LMG3422R050, LMG3425R050  
ZHCSNN4B OCTOBER 2020 REVISED MAY 2022  
www.ti.com.cn  
Table of Contents  
9.6 Device Functional Modes..........................................29  
10 Application and Implementation................................30  
10.1 Application Information........................................... 30  
10.2 Typical Application.................................................. 31  
10.3 Do's and Don'ts.......................................................34  
11 Power Supply Recommendations..............................35  
11.1 Using an Isolated Power Supply............................. 35  
11.2 Using a Bootstrap Diode......................................... 35  
12 Layout...........................................................................37  
12.1 Layout Guidelines................................................... 37  
12.2 Layout Examples.................................................... 39  
13 Device and Documentation Support..........................41  
13.1 Documentation Support.......................................... 41  
13.2 接收文档更新通知................................................... 41  
13.3 支持资源..................................................................41  
13.4 Trademarks.............................................................41  
13.5 Electrostatic Discharge Caution..............................41  
13.6 Export Control Notice..............................................41  
13.7 术语表..................................................................... 41  
14 Mechanical, Packaging, and Orderable  
1 特性................................................................................... 1  
2 应用................................................................................... 1  
3 说明................................................................................... 1  
4 Revision History.............................................................. 2  
5 Device Comparison.........................................................3  
6 Pin Configuration and Functions...................................4  
7 Specifications.................................................................. 5  
7.1 Absolute Maximum Ratings........................................ 5  
7.2 ESD Ratings............................................................... 5  
7.3 Recommended Operating Conditions.........................5  
7.4 Thermal Information....................................................6  
7.5 Electrical Characteristics.............................................6  
7.6 Switching Characteristics............................................8  
7.7 Typical Characteristics..............................................10  
8 Parameter Measurement Information..........................12  
8.1 Switching Parameters...............................................12  
9 Detailed Description......................................................15  
9.1 Overview...................................................................15  
9.2 Functional Block Diagram.........................................16  
9.3 Feature Description...................................................17  
9.4 Start Up Sequence....................................................27  
9.5 Safe Operation Area (SOA)...................................... 28  
Information.................................................................... 41  
4 Revision History  
以前版本的页码可能与当前版本的页码不同  
Changes from Revision A (April 2021) to Revision B (May 2022)  
Page  
• 将数据表状态从“预告信息”更改为“量产数据”.............................................................................................1  
Copyright © 2022 Texas Instruments Incorporated  
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5 Device Comparison  
DUAL OVERCURRENT /  
SHORT-CIRCUIT PROTECTION  
OPERATIONAL IDEAL-DIODE  
DEVICE NAME  
TEMPERATURE REPORTING  
MODE  
LMG3422R050  
LMG3425R050  
Yes  
Yes  
Yes  
Yes  
No  
Yes  
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6 Pin Configuration and Functions  
DRAIN  
15 14  
13 12 11 10  
9
8
7
6
5
4
3
2
1
16  
17  
54  
NC2  
NC2  
18  
19  
20  
21  
22  
23  
24  
25  
26  
53  
52  
51  
50  
49  
48  
47  
46  
45  
LDO5V  
RDRV  
TEMP  
OC  
THERMAL PAD  
GND  
FAULT  
IN  
VDD  
GND  
27  
44  
GND  
28  
29 30  
31 32 33 34 35 36 37 38  
39 40 41 42  
43  
VNEG  
SOURCE  
6-1. RQZ Package 54-Pin VQFN (Top View)  
6-1. Pin Functions  
PIN  
TYPE(1)  
DESCRIPTION  
NAME  
NC1  
NO.  
1, 16  
2-15  
Used to anchor QFN package to PCB. Pins must be soldered to PCB landing pads. The PCB landing pads  
are non-solder mask defined pads and must not be physically connected to any other metal on the PCB.  
Internally connected to DRAIN.  
DRAIN  
NC2  
P
GaN FET drain. Internally connected to NC1.  
Used to anchor QFN package to PCB. Pins must be soldered to PCB landing pads. The PCB landing pads  
are non-solder mask defined pads and must not be physically connected to any other metal on the PCB.  
Internally connected to SOURCE, GND, and THERMAL PAD.  
17, 54  
SOURCE  
VNEG  
18-40  
41-42  
P
P
GaN FET source. Internally connected to GND, NC2, and THERMAL PAD.  
Internal buck-boost converter negative output. Used as the negative supply to turn off the depletion mode  
GaN FET. Bypass to ground with a 2.2-µF capacitor.  
BBSW  
GND  
VDD  
IN  
43  
44, 45, 49  
46  
P
G
P
I
Internal buck-boost converter switch pin. Connect an inductor from this point to ground.  
Signal ground. Internally connected to SOURCE, NC2, and THERMAL PAD.  
Device input supply.  
47  
CMOS-compatible non-inverting input used to turn the FET on and off.  
Push-pull digital output that asserts low during a fault condition. Refer to Fault Detection for details.  
FAULT  
48  
O
Push-pull digital output that asserts low during overcurrent and short-circuit fault conditions. Refer to Fault  
Detection for details.  
OC  
50  
51  
O
O
Push-pull digital output that gives information about the GaN FET temperature. Outputs a fixed 9-kHz pulsed  
waveform. The device temperature is encoded as the duty cycle of the waveform.  
TEMP  
Drive strength selection pin. Connect a resistor from this pin to ground to set the turn-on drive strength to  
control slew rate. Tie the pin to GND to enable 150 V/ns and tie the pin to LDO5V to enable 100 V/ns.  
RDRV  
52  
53  
I
LDO5V  
P
5-V LDO output for external digital isolator  
THERMAL  
PAD  
Thermal pad. Internally connected to SOURCE, GND, and NC2. The thermal pad can be used to conduct  
rated device current.  
(1) I = input, O = output, P = power, G = ground  
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7 Specifications  
7.1 Absolute Maximum Ratings  
Unless otherwise noted: voltages are respect to GND(1)  
MIN  
MAX  
600  
UNIT  
V
VDS  
Drain-source voltage, FET off  
VDS(surge) Drain-source voltage, FET switching, surge condition(2)  
720  
V
VDS(tr)  
Drain-source transient ringing peak voltage, FET off, surge condition(2) (3)  
800  
V
(surge)  
VDD  
20  
5.5  
V
V
V
V
V
0.3  
0.3  
LDO5V  
VNEG  
0.3  
16  
BBSW  
VVDD+0.5  
20  
V
VNEG1  
0.3  
Pin voltage  
IN  
VLDO5V+0.  
3
FAULT, OC, TEMP  
RDRV  
V
0.3  
0.3  
5.5  
44  
V
A
ID(RMS)  
ID(pulse)  
Drain RMS current, FET on  
Internally  
Limited  
Drain pulsed current, FET on, tp < 10 µs(4)  
A
96  
IS(pulse)  
TJ  
Source pulsed current, FET off, tp < 1 µs  
Operating junction temperature(5)  
Storage temperature  
60  
150  
150  
A
°C  
°C  
40  
55  
Tstg  
(1) Stresses beyond those listed under Absolute Maximum Rating may cause permanent damage to the device. These are stress ratings  
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under  
Recommended Operating Condition. Exposure to absolute-maximum-rated conditions for extended periods may affect device  
reliability.  
(2) See 9.3.3 for an explanation of the switching cycle drain-source voltage ratings.  
(3) t1 < 200 ns in 9-1.  
(4) The positive pulsed current must remain below the overcurrent threshold to avoid the FET being automatically shut off. The FET drain  
intrinsic positive pulsed current rating for tp < 10 µs is 96 A.  
(5) Refer to the Electrical and Switching Characteristics Tables for junction temperature test conditions.  
7.2 ESD Ratings  
PARAMETER  
VALUE  
±2000  
±500  
UNIT  
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001(1)  
Charged-device model (CDM), per ANSI/ESDA/JEDEC JS-002(2)  
V(ESD)  
Electrostatic discharge  
V
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.  
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.  
7.3 Recommended Operating Conditions  
Unless otherwise noted: voltages are respect to GND, SOURCE connected to GND  
MIN  
7.5  
0
NOM  
12  
MAX  
UNIT  
VDD  
Supply voltage  
(Maximum switching frequency derated  
for VVDD < 9 V)  
18  
V
Input voltage  
IN  
5
18  
32  
V
A
ID(RMS)  
Drain RMS current  
Positive source current  
LDO5V  
25  
mA  
kΩ  
uF  
RRDRV  
CVNEG  
RDRV to GND resistance from external slew-rate control resistor  
VNEG to GND capacitance from external bypass capacitor  
0
1
500  
10  
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7.3 Recommended Operating Conditions (continued)  
Unless otherwise noted: voltages are respect to GND, SOURCE connected to GND  
MIN  
NOM  
MAX  
10  
UNIT  
LBBSW  
BBSW to GND inductance from external buck-boost inductor (1)  
3
4.7  
uH  
(1) > 1 A current rating is recommended.  
7.4 Thermal Information  
LMG342xR050  
RQZ (VQFN)  
54 PINS  
THERMAL METRIC(1)  
UNIT  
RθJC(bot,avg)  
Junction-to-case (bottom) average thermal resistance  
0.88  
°C/W  
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application  
report.  
7.5 Electrical Characteristics  
Unless otherwise noted: voltage, resistance, capacitance, and inductance are respect to GND; 40TJ 125;  
VDS = 480 V; 9 V VVDD 18 V; VIN = 0 V; RDRV connected to LDO5V; LBBSW = 4.7 µH  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
GAN POWER TRANSISTOR  
VIN = 5 V, TJ = 25°C  
43  
73  
3.8  
5.3  
1
55  
mΩ  
mΩ  
V
RDS(on)  
Drain-source on resistance  
VIN = 5 V, TJ = 125°C  
IS = 0.1 A  
Third-quadrant mode source-drain  
voltage  
VSD  
IS = 15 A  
3
V
VDS = 600 V, TJ = 25°C  
VDS = 600 V, TJ = 125°C  
VDS = 400 V  
uA  
uA  
pF  
IDSS  
Drain leakage current  
Output capacitance  
7
COSS  
CO(er)  
110  
Energy related effective output  
capacitance  
155  
235  
pF  
pF  
Time related effective output  
capacitance  
VDS = 0 V to 400 V  
CO(tr)  
QOSS  
QRR  
Output charge  
100  
0
nC  
nC  
Reverse recovery charge  
VDD SUPPLY CURRENTS  
VDD quiescent current (LMG3422)  
VVDD = 12 V, VIN = 0 V or 5V  
700  
780  
9
1200  
1300  
10.5  
uA  
uA  
VDD quiescent current (LMG3425)  
VDD operating current  
VVDD = 12 V, VIN = 0 V or 5V  
VVDD = 12 V, fIN = 140 kHz, soft-switching  
mA  
BUCK BOOST CONVERTER  
VNEG output voltage  
VNEG sinking 40 mA  
V
A
14  
Peak BBSW sourcing current at low  
IBBSW,PK(low peak current mode setting  
0.3  
0.4  
0.5  
(Peak external buck-boost inductor  
current)  
)
Peak BBSW sourcing current at high  
IBBSW,PK(hig peak current mode setting  
0.8  
1
1.2  
A
(Peak external buck-boost inductor  
h)  
current)  
High peak current mode setting  
enable IN positive-going threshold  
frequency  
280  
420  
515  
kHz  
LDO5V  
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7.5 Electrical Characteristics (continued)  
Unless otherwise noted: voltage, resistance, capacitance, and inductance are respect to GND; 40TJ 125;  
VDS = 480 V; 9 V VVDD 18 V; VIN = 0 V; RDRV connected to LDO5V; LBBSW = 4.7 µH  
PARAMETER  
TEST CONDITIONS  
MIN  
4.75  
25  
TYP  
MAX  
5.25  
100  
UNIT  
V
Output voltage  
LDO5V sourcing 25 mA  
5
Short-circuit current  
50  
mA  
IN  
VIN,IT+  
VIN,IT–  
Positive-going input threshold voltage  
Negative-going input threshold voltage  
Input threshold hysteresis  
1.7  
0.7  
0.7  
100  
1.9  
1
2.45  
1.3  
V
V
0.9  
150  
1.3  
V
Input pulldown resistance  
VIN = 2 V  
200  
kΩ  
FAULT, OC, TEMP OUPUT DRIVE  
Low-level output voltage  
Output sinking 8 mA  
0.16  
0.2  
0.4  
V
V
Output sourcing 8 mA, Measured as  
High-level output voltage  
0.45  
V
LDO5V VO  
VDD, VNEG UNDER VOLTAGE LOCKOUT  
VVDD,T+  
VDD UVLO positive-going threshold  
voltage  
6.5  
6.1  
7
6.5  
7.5  
7
V
V
(UVLO)  
VDD UVLO negative-going threshold  
voltage  
VDD UVLO Input threshold voltage  
hysteresis  
510  
mV  
V
VNEG UVLO negative-going  
threshold voltage  
13.6  
13.0  
12.3  
12.1  
VNEG UVLO positive-going  
threshold voltage  
V
13.2 12.75  
GATE DRIVER  
From VDS < 320 V to VDS < 80 V, RDRV  
disconnected from LDO5V, RRDRV = 300  
k, TJ = 25, VBUS = 400 V, LHB current  
= 10 A, see 8-1  
20  
V/ns  
V/ns  
V/ns  
MHz  
From VDS < 320 V to VDS < 80 V, RDRV  
tied to LDO5V, TJ = 25, VBUS = 400 V,  
LHB current = 10 A, see 8-1  
100  
Turn-on slew rate  
From VDS < 320 V to VDS < 80 V, RDRV  
disconnected from LDO5V, RRDRV = 0 ,  
TJ = 25, VBUS = 400 V, LHB current = 10  
A, see 8-1  
150  
VNEG rising to > 13.25 V, soft-switched,  
maximum switching frequency derated for  
VVDD < 9 V  
Maximum GaN FET switching  
frequency.  
3.6  
FAULTS  
DRAIN overcurrent fault threshold  
current  
IT(OC)  
40  
60  
50  
75  
60  
90  
A
A
DRAIN short-circuit fault threshold  
current  
IT(SC)  
di/dt threshold between overcurrent and  
short-circuit faults  
di/dtT(SC)  
150  
A/µs  
°C  
GaN temperature fault postive-going  
threshold temperature  
175  
30  
GaN Temperature fault threshold  
temperature hysteresis  
°C  
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7.5 Electrical Characteristics (continued)  
Unless otherwise noted: voltage, resistance, capacitance, and inductance are respect to GND; 40TJ 125;  
VDS = 480 V; 9 V VVDD 18 V; VIN = 0 V; RDRV connected to LDO5V; LBBSW = 4.7 µH  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
Driver temperature fault positive-  
going threshold temperature  
185  
°C  
Driver Temperature fault threshold  
temperature hysteresis  
20  
°C  
TEMP  
Output Frequency  
4.5  
9
82  
14  
kHz  
%
GaN TJ = 150℃  
58.5  
36.2  
0.3  
64.6  
40  
70  
43.7  
6
%
GaN TJ = 125℃  
GaN TJ = 85℃  
GaN TJ = 25℃  
Output PWM Duty Cycle  
%
3
%
IDEAL-DIODE MODE CONTROL  
Drain-source third-quadrant detection  
VT(3rd)  
0
0.15  
V
0.15  
threshold voltage  
0
0
0.2  
A
A
0TJ 125℃  
40TJ 0℃  
0.2  
Drain zero-current detection –  
threshold current  
IT(ZC)  
0.35  
0.35  
7.6 Switching Characteristics  
Unless otherwise noted: voltage, resistance, capacitance, and inductance are respect to GND; 40TJ 125;  
VDS = 480 V; 9 V VVDD 18 V; VIN = 0 V; RDRV connected to LDO5V; LBBSW = 4.7 µH  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
SWITCHING TIMES  
From VIN > VIN,IT+ to ID > 1 A, VBUS = 400  
V, LHB current = 10 A, see 8-1 and 图  
8-2  
td(on)  
Drain-current turn-on delay time  
Turn-on delay time  
28  
32  
42  
52  
4
ns  
ns  
ns  
ns  
ns  
ns  
(Idrain)  
From VIN > VIN,IT+ to VDS < 320 V, VBUS  
400 V, LHB current = 10 A, see 8-1  
and 8-2  
=
td(on)  
tr(on)  
td(off)  
tf(off)  
From VDS < 320 V to VDS < 80 V, VBUS  
400 V, LHB current = 10 A, see 8-1  
and 8-2  
=
Turn-on rise time  
2.5  
44  
From VIN < VIN ,ITto VDS > 80 V, VBUS  
400 V, LHB current = 10 A, see 8-1  
and 8-2  
=
Turn-off delay time  
65  
21  
24  
From VDS > 80 V to VDS > 320 V, VBUS  
400 V, LHB current = 10 A, see 8-1  
and 8-2  
=
Turn-off fall time(1)  
VIN rise/fall times < 1 ns, VDS falls to <  
200 V, VBUS = 400 V, LHB current = 10 A,  
see 8-1  
Minimum IN high pulse-width for FET  
turn-on  
STARTUP TIMES  
From VVDD > VVDD,T+  
(UVLO) to FAULT high, CLDO5V = 100  
nF, CVNEG = 2.2 µF at 0-V bias linearly  
decreasing to 1.5 µF at 15-V bias  
t(start)  
Driver start-up time  
310  
110  
470  
145  
us  
ns  
FAULT TIMES  
Overcurrent fault FET turn-off time, FET  
on before overcurrent  
VIN = 5 V, From ID > IT(OC) to ID < 50 A, ID  
di/dt = 100 A/µs  
toff(OC)  
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7.6 Switching Characteristics (continued)  
Unless otherwise noted: voltage, resistance, capacitance, and inductance are respect to GND; 40TJ 125;  
VDS = 480 V; 9 V VVDD 18 V; VIN = 0 V; RDRV connected to LDO5V; LBBSW = 4.7 µH  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
Short-circuit current fault FET turn-off  
time, FET on before short circuit  
VIN = 5 V, From ID > IT(SC) to ID < 50 A, ID  
di/dt = 700 A/µs  
toff(SC)  
65  
100  
ns  
Overcurrent fault FET turn-off time, FET  
turning on into overcurrent  
From ID > IT(OC) to ID < 50 A  
200  
250  
ns  
Short-circuit fault FET turn-off time, FET  
turning on into short circuit  
From ID > IT(SC) to ID < 50 A  
100  
380  
50  
180  
580  
ns  
us  
ns  
IN reset time to clear FAULT latch  
From VIN < VIN,ITto FAULT high  
250  
t(window)  
Overcurrent fault to short-circuit fault  
window time  
(OC)  
IDEAL-DIODE MODE CONTROL TIMES  
VDS < VT(3rd) to FET turn-on, VDS being  
discharged by half-bridge configuration  
inductor at 5 A  
Ideal-diode mode FET turn-on time  
50  
65  
ns  
ID > IT(ZC) to FET turn-off, ID di/dt = 100  
A/µs created with a half-bridge  
configuration  
Ideal-diode mode FET turn-off time  
50  
76  
ns  
ns  
Overtemperature-shutdown ideal-diode  
mode IN falling blanking time  
150  
230  
360  
(1) During turn-off, VDS rise time is the result of the resonance of COSS and loop inductance as well as load current.  
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7.7 Typical Characteristics  
140  
120  
100  
80  
-40C  
0C  
25C  
85C  
125C  
60  
40  
20  
0
50 100 150 200 250 300 350 400 450 500  
RDRV Resistance (k)  
7-2. Turn-On Delay Time vs Drive Strength Resistance  
7-1. Drain-Current Turn-On Delay Time vs Drive Strength  
Resistance  
18  
140  
-40C  
-40C  
16  
0C  
0C  
120  
25C  
85C  
125C  
25C  
14  
85C  
100  
125C  
12  
80  
60  
40  
20  
0
10  
8
6
4
2
0
0
50 100 150 200 250 300 350 400 450 500  
0
50 100 150 200 250 300 350 400 450 500  
RDRV Resistance (k)  
RDRV Resistance (k)  
7-4. Turn-On Slew Rate vs Drive Strength Resistance  
7-3. Turn-On Rise Time vs Drive Strength Resistance  
350  
8
-40C  
7.5  
0C  
300  
250  
25C  
7
85C  
125C  
6.5  
6
200  
-40C  
5.5  
5
25C  
150  
100  
50  
125C  
OC limit  
4.5  
4
3.5  
3
0
0
5
10  
15  
20  
25  
30  
35  
40  
45  
0
5
10  
15  
20  
25  
30  
35  
Drain-Source Voltage (V)  
Source Current (A)  
7-5. Drain Current vs Drain-Source Voltage  
IN = 0 V  
7-6. Off-State Source-Drain Voltage vs Source Current  
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7.7 Typical Characteristics (continued)  
800  
700  
600  
500  
400  
300  
200  
100  
0
2
1.8  
1.6  
1.4  
1.2  
1
-40C  
0C  
25C  
85C  
125C  
0.8  
0.6  
0
50 100 150 200 250 300 350 400 450 500  
Drain-Source Voltage (V)  
-40 -20  
0
20  
40  
60  
80 100 120 140 160  
Junction Temperature(C)  
7-8. Output Capacitance vs Drain-Source Voltage  
7-7. Normalized On-Resistance vs Junction Temperatue  
250  
VDS = 0 V  
VDS = 50 V  
VDS = 400 V  
200  
150  
100  
50  
VDS = 400 V  
VDS = 50 V  
VDS = 0 V  
0
0
400 800 1200 1600 2000 2400 2800 3200 3600  
IN Switching Frequency (kHz)  
VDD = 12 V;  
TJ = 25 °C.  
VDD = 12 V;  
TJ = 125 °C.  
7-9. VDD Supply Current vs IN Switching Frequency  
7-10. VDD Supply Current vs IN Switching Frequency  
100  
45  
40  
35  
30  
25  
20  
15  
10  
5
80  
60  
40  
Turn-On Switching Energy (J)  
Turn-Off Switching Energy (J)  
20  
0
0
0
3
6
9
12  
15  
18  
21  
24  
27  
30  
0
50 100 150 200 250 300 350 400 450 500  
Drain-Source Voltage (V)  
Inductive Load Current (A)  
7-11. Half-Bridge Switching Energy vs Inductive Load  
7-12. Repetitive Safe Operation Area  
Current  
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8 Parameter Measurement Information  
8.1 Switching Parameters  
8-1 shows the circuit used to measure most switching parameters. The top device in this circuit is used to re-  
circulate the inductor current and functions in third-quadrant mode only. Only the LMG3422R050 must be used  
as the top device as it does not have the ideal-diode mode feature. Do not use the LMG3425R050 for the top  
device. If the top device has the ideal-diode mode feature, it will automatically turn on the GaN FET when the  
inductor current is re-circulating and cause a shoot-through current event when the bottom device turns on. The  
bottom device is the active device that turns on to increase the inductor current to the desired test current. The  
bottom device is then turned off and on to create switching waveforms at a specific inductor current. Both the  
drain current (at the source) and the drain-source voltage is measured. 8-2 shows the specific timing  
measurement. TI recommends to use the half-bridge as double pulse tester. Excessive third-quadrant operation  
can overheat the top device.  
DRAIN  
Slew  
Rate  
Direct- Drive  
SOURCE  
GaN  
RDRV  
IN  
VDD  
VNEG  
OCP, OTP, Current  
UVLO,  
TEMP  
LDO,  
BB  
LDO5V  
LHB  
TEMP  
FAULT  
OC  
VBUS  
+
œ
SOURCE  
CPCB  
DRAIN  
Slew  
Rate  
Direct- Drive  
SOURCE  
GaN  
RDRV  
IN  
+
VDD  
VNEG  
VDS  
_
OCP, OTP,  
UVLO,  
TEMP  
Current  
LDO,  
BB  
LDO5V  
TEMP  
PWM input  
FAULT  
OC  
SOURCE  
8-1. Circuit Used to Determine Switching Parameters  
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50%  
50%  
IN  
ID  
td(on)(Idrain)  
1A  
td(on)  
td(off)  
tr(on)  
tf(off)  
VDS  
80%  
80%  
20%  
20%  
8-2. Measurement to Determine Propagation Delays and Slew Rates  
8.1.1 Turn-On Times  
The turn-on transition has three timing components: drain-current turn-on delay time, turn-on delay time, and  
turn-on rise time. The drain-current turn-on delay time is from when IN goes high to when the GaN FET drain-  
current reaches 1 A. The turn-on delay time is from when IN goes high to when the drain-source voltage falls  
20% below the bus voltage. Finally, the turn-on rise time is from when drain-source voltage falls 20% below the  
bus voltage to when the drain-source voltage falls 80% below the bus voltage. Note that the turn-on rise time is  
the same as the VDS 80% to 20% fall time. All three turn-on timing components are a function of the RDRV pin  
setting.  
8.1.2 Turn-Off Times  
The turn-off transition has two timing components: turn-off delay time, and turn-off fall time. The turn-off delay  
time is from when IN goes low to when the drain-source voltage rises to 20% of the bus voltage. The turn-off fall  
time is from when the drain-source voltage rises to 20% of the bus voltage to when the drain-source voltage  
rises to 80% of the bus voltage. Note that the turn-off fall time is the same as the VDS 20% to 80% rise time. The  
turn-off timing components are independent of the RDRV pin setting, but heavily dependent on the LHB load  
current.  
8.1.3 Drain-Source Turn-On Slew Rate  
The drain-source turn-on slew rate, measured in volts per nanosecond, is the inverse of the turn-on rise time or  
equivalently the inverse of the VDS 80% to 20% fall time. The RDRV pin is used to program the slew rate.  
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8.1.4 Turn-On and Turn-Off Switching Energy  
The turn-on and turn-off switching energy shown in 7-11 represent the energy absorbed by the low-side  
device during the turn-on and turn-off transients of the circuit. As the circuit in 8-1 represents a boost  
converter with input shorted to output, the switching energy is dissipated in the low-side device. The turn-on  
transition is lossy while the turn-off transition is essentially lossless with the output capacitance energy charged  
by the inductor current. The turn-on and turn-off losses have been calculated from experimental waveforms by  
integrating the product of the drain current with the drain-source voltage over the turn-on and turn-off times,  
respectively. The skew of probes for voltage and current are very important for accurate measurement of turn-on  
and turn-off energy.  
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9 Detailed Description  
9.1 Overview  
The LMG342xR050 is a high-performance power GaN device with integrated gate driver. The GaN device offers  
zero reverse recovery and ultra-low output capacitance, which enables high efficiency in bridge-based  
topologies. Direct Drive architecture is applied to control the GaN device directly by the integrated gate driver.  
This architecture provides superior switching performance compared to the traditional cascode approach and  
helps solve a number of challenges in GaN applications.  
The integrated driver ensures the device stays off for high drain slew rates. The integrated driver also protects  
the GaN device from overcurrent, short-circuit, undervoltage, and overtemperature. Regarding fault signal  
reporting, LMG342xR050 provides different reporting method which is shown in 9-1. Refer to Fault Detection  
for more details. The integrated driver is also able to sense the die temperature and send out the temperature  
signal through a modulated PWM signal.  
Unlike Si MOSFETs, GaN devices do not have a p-n junction from source to drain and thus have no reverse  
recovery charge. However, GaN devices still conduct from source to drain similar to a p-n junction body diode,  
but with higher voltage drop and higher conduction loss. Therefore, source-to-drain conduction time must be  
minimized while the LMG342xR050 GaN FET is turned off. The ideal-diode mode feature in the LMG3425R050  
automatically minimizes the source-to-drain conduction loss that occur on the GaN FET soft-switched turn-on  
edge, similar to optimum dead-time control.  
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9.2 Functional Block Diagram  
TEMP  
DRAIN  
VDD  
Third-Quadrant  
Detection  
GaN  
LDO  
LDO5V  
UVLO  
(+5V, VDD, VNEG)  
FAULT  
Series  
Si FET  
Die  
Temp  
Sensing  
Thermal  
Shutdown  
Short Circuit Protection  
Overcurrent Protection  
OC  
IN  
Gating logic control  
& level shifting  
Buck-Boost  
Controller  
BBSW  
VNEG  
SOURCE  
RDRV  
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9.3 Feature Description  
The LMG342xR050 includes advanced features to provide superior switching performance and converter  
efficiency.  
9.3.1 GaN FET Operation Definitions  
For the purposes of this data sheet, the following terms are defined below. The SOURCE pin is assumed to be at  
0 V for these definitions.  
First-Quadrant Current = Positive current flowing internally from the DRAIN pin to the SOURCE pin.  
Third-Quadrant Current = Positive current flowing internally from the SOURCE pin to the DRAIN pin.  
First-Quadrant Voltage = Drain pin voltage Source pin voltage = Drain pin voltage  
Third-Quadrant Voltage = SOURCE pin voltage DRAIN pin voltage = DRAIN pin voltage  
FET On-State = FET channel is at rated RDS(on). Both first-quadrant current and third-quadrant current can flow  
at rated RDS(on)  
.
For LMG342xR050 in On-State, GaN FET internal gate voltage is held at the SOURCE pin voltage to achieve  
rated RDS(on). The GaN FET channel is at rated RDS(on) with VGS = 0 V because the LMG342xR050 GaN FET is  
a depletion mode FET.  
FET Off-State = FET channel is fully off for positive first-quadrant voltage. No first-quadrant current can flow.  
While first-quadrant current cannot flow in the FET Off-State, third-quadrant current still flows if the DRAIN  
voltage is taken sufficiently negative (positive third-quadrant voltage). For devices with an intrinsic p-n junction  
body diode, current flow begins when the DRAIN voltage drops enough to forward bias the p-n junction.  
GaN FETS do not have an intrinsic p-n junction body diode. Instead, current flows because the GaN FET  
channel turns back on. In this case, the DRAIN pin becomes the electrical source and the SOURCE pin  
becomes the electrical drain. To enhance the channel in third-quadrant, the DRAIN (electrical source) voltage  
must be taken sufficiently low to establish a VGS voltage greater than the GaN FET threshold voltage. The GaN  
FET channel is operating in saturation and only turns on enough to support the third-quadrant current as its  
saturated current.  
For LMG342xR050 in Off-State, GaN FET internal gate voltage is held at the VNEG pin voltage to block all first-  
quadrant current. The VNEG voltage is lower than the GaN FET negative threshold voltage to cut off the  
channel.  
To enhance the channel in off-state third quadrant, the LMG342xR050 DRAIN (electrical source) voltage must be  
taken sufficiently close to VNEG to establish a VGS voltage greater than the GaN FET threshold voltage. Again,  
because the LMG342xR050 GaN FET is a depletion mode FET with a negative threshold voltage, this means  
the GaN FET turns on with DRAIN (electrical source) voltage between 0 V and VNEG. The typical off-state third-  
quadrant voltage is 5.3 V for third-quadrant current at 15 A. Thus, the off-state third-quadrant losses for the  
LMG342xR050 are significantly higher than a comparable power device with an intrinsic p-n junction body diode.  
The ideal-diode mode function described in Ideal-Diode Mode Operation can help mitigate these losses in  
specific situations.  
9.3.2 Direct-Drive GaN Architecture  
The LMG342xR050 uses a series Si FET to ensure the power IC stays off when VDD bias power is not applied.  
When the VDD bias power is off, the series Si FET is interconnected with the GaN device in a cascode mode,  
which is shown in the Functional Block Diagram. The gate of the GaN device is held within a volt of the series Si  
FET's source. When a high voltage is applied on the module and the silicon FET blocks the drain voltage, the  
VGS of the GaN device decreases until the GaN device passes the threshold voltage. Then, the GaN device is  
turned off and blocks the remaining major part of drain voltage. There is an internal clamp to make sure that the  
VDS does not exceed its maximum rating. This feature avoids the avalanche of the series Si FET when there is  
no bias power.  
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When LMG342xR050 is powered up with VDD bias power, the internal buck-boost converter generates a  
negative voltage (VVNEG) that is sufficient to directly turn off the GaN device. In this case, the series Si FET is  
held on and the GaN device is gated directly with the negative voltage.  
Comparing with traditional cascode drive GaN architecture, where the GaN gate is grounded and the Si  
MOSFET gate is being driven to control the GaN device, direct-drive configuration has multiple advantages.  
First, as the Si MOSFET does need to switch in every switching cycle, GaN gate-to-source charge (QGS) is lower  
and theres no Si MOSFET reverse-recovery related losses. Second, the voltage distribution between the GaN  
and Si MOSFET in off-mode in a cascode configuration can cause the MOSFET to avalanche due to high GaN  
drain-to-source capacitance (CDS). Finally, the switching slew rate in direct-drive configuration can be controlled  
while cascode drive cannot. More information about the direct-drive GaN architecture can be found in Direct-  
drive configuration for GaN devices.  
9.3.3 Drain-Source Voltage Capability  
Due to the silicon FETs long reign as the dominant power-switch technology, many designers are unaware  
that the headline drain-source voltage cannot be used as an equivalent point to compare devices across  
technologies. The headline drain-source voltage of a silicon FET is set by the avalanche breakdown voltage.  
The headline drain-source voltage of a GaN FET is set by the long term reliability with respect to data sheet  
specifications.  
Exceeding the headline drain-source voltage of a silicon FET can lead to immediate and permanent damage.  
Meanwhile, the breakdown voltage of a GaN FET is much higher than the headline drain-source voltage. For  
example, the breakdown voltage of the LMG342xR050 is more than 800 V.  
A silicon FET is usually the weakest link in a power application during an input voltage surge. Surge protection  
circuits must be carefully designed to ensure the silicon FET avalanche capability is not exceeded because it is  
not feasible to clamp the surge below the silicon FET breakdown voltage. Meanwhile, it is easy to clamp the  
surge voltage below a GaN FET breakdown voltage. In fact, a GaN FET can continue switching during the surge  
event which means output power is safe from interruption.  
The LMG342xR050 drain-source capability is explained with the assistance of 9-1. The figure shows the  
drain-source voltage versus time for a GaN FET for a single switch cycle in a switching application. No claim is  
made about the switching frequency or duty cycle.  
VDS(tr)  
VDS(off)  
VDS(switching)  
t0 t1  
t2  
9-1. Drain-Source Voltage Switching Cycle  
The waveform starts before t0 with the FET in the on state. At t0 the GaN FET turns off and parasitic elements  
cause the drain-source voltage to ring at a high frequency. The peak ring voltage is designated VDS(tr). The high  
frequency ringing has damped out by t1. Between t1 and t2 the FET drain-source voltage is set by the  
characteristic response of the switching application. The characteristic is shown as a flat line, but other  
responses are possible. The voltage between t1 and t2 is designated VDS(off). At t2 the GaN FET is turned on at a  
non-zero drain-source voltage. The drain-source voltage at t2 is designated VDS(switching). Unique VDS(tr), VDS(off)  
and VDS(switching) parameters are shown because each can contribute to stress over the lifetime of the GaN FET.  
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The LMG342xR050 drain-source surge voltage capability is seen with the absolute maximum ratings VDS(tr)(surge)  
and VDS(surge) in the Specifications where VDS(tr)(surge) maps to VDS(tr) in 9-1 and VDS(surge) maps to both  
VDS(off) and VDS(switching) in 9-1. More information about the surge capability of TI GaN FETs is found in A New  
Approach to Validate GaN FET Reliability to Power-line Surges Under Use-conditions.  
9.3.4 Internal Buck-Boost DC-DC Converter  
An internal inverting buck-boost converter generates a regulated negative rail for the turn-off supply of the GaN  
device. The buck-boost converter is controlled by a peak current mode, hysteretic controller. In normal operation,  
the converter remains in discontinuous-conduction mode, but can enter continuous-conduction mode during  
start-up and overload the conditions. The converter is controlled internally and requires only a single surface-  
mount inductor and output bypass capacitor. Typically, the converter is designed to use a 4.7 μH inductor and a  
2.2 μF output capacitor.  
The buck-boost converter uses a peak current hysteretic control. As shown in 9-2, the inductor current  
increases at the beginning of a switching cycle until the inductor reaches the peak current limit. Then the  
inductor current goes down to zero. The idle time between each current pulse is determined automatically by the  
output current, and can be reduced to zero. Therefore, the maximum output current happens when the idle time  
is zero, and is decided by the peak current but to a first order is independent of the inductor value. However, the  
peak output current the buck-boost can deliver to the -14V rail is proportional to the VDD input voltage.  
Therefore, the maximum switching frequency of the GaN that the buck-boost can support varies with VDD  
voltage and is only specified for operation up to 3.6 MHz for VDD voltages above 9V.  
VNEG_avg  
ûVNEG  
VNEG  
IDCDC,PK  
Smaller  
inductor  
Larger  
inductor  
Idle time  
Buck-boost  
inductor current  
1/(buck-boost frequency)  
9-2. Buck-Boost Converter Inductor Current  
The LMG342xR050 supports the GaN operation up to 3.6 MHz. As power consumption is very different in a wide  
switching frequency range enabled by the GaN device, two peak current limits are used to control the buck-boost  
converter. The two ranges are separated by IN positive-going threshold frequency. As shown in 9-3, when  
switching frequency is in the lower range, the peak current is initially set to the lower value IBBSW,M(low) (typically  
0.4 A) . When switching frequency is in the higher range, the peak current is raised to the higher value  
IBBSW,M(high) (typically 1 A) and requires a larger inductor. There is a filter on this frequency detection logic,  
therefore the LMG342xR050 requires five consecutive cycles at the higher frequency before it is set to the higher  
buck-boost peak current limit. The current limit does not go down again until power off after the higher limit is set.  
Even if the switching frequency returns to the lower range, the current limit does not decrease to the lower limit.  
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IBBSW,PK(high)  
IBBSW,PK(low)  
IBBSW,PK  
IN  
9-3. Buck-Boost Converter Peak Current  
As the peak current of the buck-boost is subject to two different peak current limits which are 0.4 A and 1 A for  
low and high frequency operation (see Internal Buck-Boost DC-DC Converter), so the inductor must have a  
saturation current well above the rated peak current limit. After the higher limit is established by switching at a  
higher frequency, the current limit does not go back to the lower level even when GaN device is then switched at  
a lower frequency. Therefore, selecting an inductor according to the higher 1-A limit is recommended.  
9.3.5 VDD Bias Supply  
Wide VDD voltage ranges from 7.5 V to 18 V are supported by internal regulators which supply the bias supplies  
needed for the internal circuits to function. TI recommends to use a 12-V unregulated power supply to supply  
VDD.  
9.3.6 Auxiliary LDO  
There is a 5-V voltage regulator inside the part used to supply external loads, such as digital isolators for the  
high-side drive signal. The digital outputs of the part use this rail as their supply. No capacitor is required for  
stability, but transient response is poor if no external capacitor is provided. If the application uses this rail to  
supply external circuits, TI recommends to have a capacitor of at least 0.1 μF for improved transient response.  
A larger capacitor can be used for further transient response improvement. The decoupling capacitor used here  
must be a low-ESR ceramic type. Capacitances above 0.47 μF will slow down the start-up time of the  
LMG342xR050 due to the ramp-up time of the 5-V rail.  
9.3.7 Fault Detection  
The GaN power IC integrates overcurrent protection (OCP), short-circuit protection (SCP), overtemperature  
protection (OTP) and undervoltage lockout (UVLO).  
9.3.7.1 Overcurrent Protection and Short-Circuit Protection  
There are two types of current faults which can be detected by the driver: overcurrent fault and short-circuit fault.  
The overcurrent protection (OCP) circuit monitors drain current and compares that current signal with an  
internally set limit IT(OC). Upon detection of the overcurrent, the LMG342xR050 conducts cycle-by-cycle  
overcurrent protection as shown in 9-4. In this mode, the GaN device is shut off and the OC pin is pulled low  
when the drain current crosses the IT(OC) plus a delay toff(OC), but the overcurrent signal clears after the IN pin  
signal goes low. In the next cycle, the GaN device can turn on as normal. The cycle-by-cycle function can be  
used in cases where steady-state operation current is below the OCP level but transient response can still reach  
current limit, while the circuit operation cannot be paused. The cycle-by-cycle function also prevents the GaN  
device from overheating by overcurrent induced conduction losses.  
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The short-circuit protection (SCP) monitors the drain current and triggers if the di/dt of the current exceeds a  
threshold di/dt T(SC) as the current crosses between the OC and SC thresholds. It performs this di/dt detection by  
delaying the OC detection signal by an amount tOC,window and using a higher current SC detection threshold. If  
the delayed OC occurs before the non-delayed SC, the di/dt is below the threshold and an OC is triggered. If the  
SC is detected first, the di/dt is fast enough and the SC is detected as shown in 9-5. This extremely high di/dt  
current would typically be caused by a short of the output of the half-bridge and can be damaging for the GaN to  
continue to operate in that condition. Therefore, if a short-circuit fault is detected, the GaN device is turned off  
with an intentionally slowed driver so that a lower overshoot voltage and ringing can be achieved during the turn-  
off event. This fast response circuit helps protect the GaN device even under a hard short-circuit condition. In  
this protection, the GaN device is shut off and held off until the fault is reset by either holding the IN pin low for a  
period of time defined in the Specifications or removing power from VDD.  
During OCP or SCP in a half bridge, after the current reaches the upper limit and the device is turned off by  
protection, the PWM input of the device could still be high and the PWM input of the complementary device  
could still be low. In this case, the load current can flow through the third quadrant of the complementary device  
with no synchronous rectification. The high negative VDS of the GaN device (3 V to 5 V) from drain to source  
could lead to high third-quadrant loss, similar to dead-time loss but for a longer time.  
For safety considerations, OCP allows cycle-by-cycle operation while SCP latches the device until reset. By  
reading the FAULT and OC pins, the exact current fault type can be determined. Refer to Fault Reporting for  
detailed information.  
IT(OC)  
Inductor current  
VSW  
Input PWM  
9-4. Cycle-by-Cycle OCP Operation  
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toff(SC)  
toff(OC)  
IT(SC)  
< t(window)(OC)  
IT(OC)  
ID  
IN  
OC  
Cycle by cycle OCP  
Latched SCP  
9-5. Overcurrent Detection vs Short-Circuit Detection  
9.3.7.2 Overtemperature Shutdown  
The LMG342xR050 implements two overtemperature-shutdown (OTSD) functions, the GaN OTSD and the  
Driver OTSD. Two OTSD functions are needed to maximize device protection by sensing different locations in  
the device and protecting against different thermal-fault scenarios.  
The GaN OTSD senses the GaN FET temperature. The GaN FET can overheat from both first-quadrant current  
and third-quadrant current. As explained in GaN FET Operation Definitions, a FET can prevent first-quadrant  
current by going into the off-state but is unable to prevent third-quadrant current. FET third-quadrant losses are a  
function of the FET technology, current magnitude, and if the FET is operating in the on-state or off-state. As  
explained in GaN FET Operation Definitions, the LMG342xR050 has much higher GaN FET third-quadrant  
losses in the off-state.  
When the GaN FET is too hot, the best protection is to turn off the GaN FET when first-quadrant current tries to  
flow and turn on the GaN FET when third-quadrant current is flowing. This type of FET control is known as ideal-  
diode mode (IDM). When the GaN OTSD trip point is exceeded, the GaN OTSD puts the GaN FET into  
overtemperature-shutdown ideal-diode mode (OTSD-IDM) operation to achieve this optimum protection. OTSD-  
IDM is explained in Ideal-Diode Mode Operation.  
The Driver OTSD senses the integrated driver temperature and trips at a higher temperature compared to the  
GaN OTSD. This second OTSD function exists to protect the LMG342xR050 from driver thermal-fault events  
while allowing sufficient temperature difference for OTSD-IDM to operate. These driver thermal events include  
shorts on the LDO5V, BBSW, and VNEG device pins. When the Driver OTSD trip point is exceeded, the Driver  
OTSD shuts off the LDO5V regulator, the VNEG buck-boost converter, and the GaN FET. Note that OTSD-IDM  
does not function in Driver OTSD. This is why the Driver OTSD must trip higher than the GaN OTSD function.  
Otherwise, GaN FET third-quadrant overheating cannot be addressed.  
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Besides the temperature difference in the GaN OTSD and Driver OTSD trip points, further temperature  
separation is obtained due to the thermal gradient difference between the GaN OTSD and Driver OTSD sense  
points. The GaN OTSD sensor is typically at least 20°C hotter than the driver OTSD sensor when the device is  
in GaN OTSD due to GaN FET power dissipation.  
The FAULT pin is asserted for either or both the GaN OTSD state and the Driver OTSD state. FAULT de-asserts  
and the device automatically returns to normal operation after both the GaN OTSD and Driver OTSD fall below  
their negative-going trip points. During cool down, when the device exits the Driver OTSD state but is still in the  
GaN OTSD state, the device automatically resumes OTSD-IDM operation.  
9.3.7.3 UVLO Protection  
The LMG342xR050 supports a wide range of VDD voltages. However, when the device is below UVLO  
threshold, the GaN device stops switching and is held off. The FAULT pin is pulled low as an indication of UVLO.  
The LDO and buck-boost are turned on by the rising-edge of the VIN UVLO and shuts off around 5 V to 6 V.  
9.3.7.4 Fault Reporting  
The FAULT and OC outputs form a fault reporting scheme together. The FAULT and OC outputs are both push-  
pull outputs indicating the readiness and fault status of the driver. These two pins are logic high in normal  
operation, and change logic according to 9-1.  
9-1. Fault Types and Reporting  
NORMAL  
UVLO, OT, and RDRV-OPEN  
OVERCURRENT  
SHORT-CIRCUIT  
FAULT  
OC  
1
1
0
1
1
0
0
0
FAULT is held low when starting up until the series Si FET is turned on. During operation, if the power supplies  
go below the UVLO thresholds or the device temperature go above the OT thresholds, power device is disabled  
and FAULT is held low until a fault condition is no longer detected. If RDRV is open, FAULT is also held low. In a  
short-circuit or overtemperature fault condition, FAULT is held low until the fault latches are reset or fault is  
cleared. The OC pin is held low if there is a short-circuit or overcurrent fault. The signals help notify the controller  
the exact type of faults by reading the truth table. If a combined reporting of the faults on a single pin is desired,  
one can short the OC pin to ground during power up. All faults assert the FAULT pin then and the OC pin is not  
used. Please note: internal protection happens regardless of the connection of the pin outputs, which means that  
the protection features continue to operate even if fault reporting is ignored..  
9.3.8 Drive Strength Adjustment  
The LMG342xR050 allows users to adjust the drive strength of the device and obtain a desired slew rate, which  
provides flexibility when optimizing switching losses and noise coupling.  
To adjust drive strength, a resistor can be placed between the RDRV pin and GND pin. The resistance  
determines the slew rate of the device, from 20 V/ns to 150 V/ns, during turn-on. On the other hand, there are  
two dv/dt values that can be selected without the resistor: shorting the RDRV pin to ground sets the slew rate to  
150 V/ns, and shorting the RDRV pin to LDO5V sets the slew rate to 100 V/ns. The device detects the short to  
LDO5V one time at power up. Once the short to LDO5V condition is detected, the device no longer monitors the  
RDRV pin. Otherwise, the RDRV pin is continuously monitored and the dv/dt setting can be changed by  
modulating the resistance during device operation. The modulation must be fairly slow since there is significant  
internal filtering to reject switching noise.  
Please note: parasitic power loop inductance can influence the voltage slew rate reading from the VDS switching  
waveform.The inductance induces a drop on VDS in the current rising phase before voltage falling phase, if this  
drop is more than 20% of the VDC, the voltage slew rate reading can be influenced. Refer to 12.1.2 for the  
power loop design guideline and how to estimate the parasitic power loop inductance.  
9.3.9 Temperature-Sensing Output  
The integrated driver senses the GaN die temperature and outputs the information through a modulated PWM  
signal on the TEMP pin. The typical PWM frequency is 9 kHz with the same refresh rate. The minimum PWM  
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duty cycle is around 1%, which can be observed at temperature below 25°C. The target temperature range is  
from 25°C to 150°C, and the corresponding PWM duty cycle is typically from 3% to 82%. Following equation can  
be used to calculate the typical junction temperature TJ,typ in °C from the duty cycle DTEMP  
:
TJ,typ (°C) = 162.3 * DTEMP + 20.1  
The tolerances of typical measurement are listed in 9-2.  
9-2. Typical Junction Temperature Measurement based on TEMP Signal and Tolerance  
Typical TJ Measurement based on TEMP Signal (°C)  
25  
85  
125  
Tolerance (°C)  
± 5  
± 6  
± 10  
At temperatures above 150°C, the duty cycle continues to increase linearly until overtemperature fault happens.  
When overtemperature happens, the TEMP pin is pulled high to indicate this fault until the temperature is  
reduced to the normal range. There is a hysteresis to clear overtemperature fault.  
9.3.10 Ideal-Diode Mode Operation  
Off-state FETs act like diodes by blocking current in one direction (first quadrant) and allowing current in the  
other direction (third quadrant) with a corresponding diode like voltage drop. FETs, though, can also conduct  
third-quadrant current in the on-state at a significantly lower voltage drop. Ideal-diode mode (IDM) is when an  
FET is controlled to block first-quadrant current by going to the off-state and conduct third-quadrant current by  
going to the on-state, thus achieving an ideal lower voltage drop.  
FET off-state third-quadrant current flow is commonly seen in power converters, both in normal and fault  
situations. As explained in GaN FET Operation Definitions, GaN FETs do not have an intrinsic p-n junction body  
diode to conduct off-state third-quadrant current. Instead, the off-state third-quadrant voltage drop for the  
LMG342xR050 is several times higher than a p-n junction voltage drop, which can impact efficiency in normal  
operation and device ruggedness in fault conditions.  
To mitigate efficiency degradation, the LMG3425R050 implements an operational ideal-diode mode (OP-IDM)  
function. Meanwhile, to improve device ruggedness in a GaN FET overtemperature fault situation, all devices in  
the LMG342xR050 family implement a GaN FET overtemperature-shutdown ideal-diode mode (OTSD-IDM)  
function as referenced in Overtemperature Shutdown. Both OP-IDM and OTSD-IDM are described in more detail  
below.  
Operational Ideal-Diode Mode (LMG3425R050)  
Operational ideal-diode mode (OP-IDM) is implemented in the LMG3425R050 but not in the LMG3422R050.  
Understand that the OP-IDM function is not a general-purpose ideal-diode mode function which allows the  
LMG342xR050 to autonomously operate as a diode, including as an autonomous synchronous rectifier.  
Furthermore, the OP-IDM function is not intended to support an ideal-diode mode transition from the on-state to  
the off-state in a high-voltage, hard-switched application. Exposing the LMG342xR050 to this situation is akin to  
operating a half-bridge power stage with negative dead time with corresponding high shoot-through current.  
Instead, as described below, the LMG342xR050 OP-IDM function is narrowly implemented to address a specific  
off-state third-quadrant current flow situation while minimizing situations where the ideal-diode mode can create  
a dangerous shoot-through current event.  
OP-IDM is intended to minimize GaN FET off-state third-quadrant losses that occur in a zero-voltage switched  
(ZVS) event. ZVS events are seen in applications such as synchronous rectifiers and LLC converters. The ZVS  
event occurs at the FET off-state to on-state transition when an inductive element discharges the FET drain  
voltage before the FET is turned-on. The discharge ends with the inductive element pulling the FET drain-source  
voltage negative and the FET conducting off-state third-quadrant current.  
Power supply controllers use dead-time control to set the time for the ZVS event to complete before turning on  
the FET. Both the ZVS time and resulting FET off-state third-quadrant current are a function of the power  
converter operation. Long ZVS time and low third-quadrant current occur when the inductive element is slewing  
the FET with low current and short ZVS time and high third-quadrant current occur when the inductive element is  
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slewing at the FET with high current. Sophisticated controllers optimally adjust the dead time to minimize third-  
quadrant losses. Simpler controllers use a fixed dead time to handle the longest possible ZVS time. Thus, in a  
fixed dead-time application, the highest possible off-state third-quadrant losses occur for the longest possible  
time.  
OP-IDM mitigates the losses in a fixed dead-time application by automatically turning on the GaN FET as soon  
as third-quadrant current is detected. In this sense, OP-IDM can be described as providing a turn-on assist  
function with optimum dead-time control. Meanwhile, OP-IDM is not intended to be used to turn-off the GaN FET  
in normal operation. OP-IDM turnoff capability is only provided as a protection mechanism to guard against  
shoot-through current.  
OP-IDM works within the confines of normal LMG342xR050 switching operation as controlled by the IN pin. The  
key consideration for the OP-IDM operation is to ensure the turn-on assist function is only activated on the ZVS  
edge. For example, third-quadrant current is seen in a LMG342xR050 used as a synchronous rectifier both  
before the IN pin goes high to turn on the GaN FET and after the IN pin goes low to turn off the GaN FET. OP-  
IDM turns on the GaN FET before the IN pin goes high when OP-IDM detects third-quadrant current. But it would  
be a mistake for OP-IDM to turn the GaN FET back on right after IN has turned it off because OP-IDM detects  
third-quadrant current. If OP-IDM were to turn on the GaN FET in this situation, it would create a shoot-through  
current event when the opposite-side power switch turns on. OP-IDM avoids this shoot-through current problem  
on the turn-off edge by requiring the drain voltage to first go positive before looking for the ZVS event.  
The OP-IDM state machine is shown in 9-6. Each state is assigned a state number in the upper right side of  
the state box.  
IN low  
1
5
FET OFF  
FET ON  
OP-IDM looking for  
positive VDS  
OP-IDM idle  
IN high  
IN high  
Positive VDS  
IN high  
IN high  
4
2
3
FET OFF  
FET ON  
FET Off  
OP-IDM looking for  
negative VDS  
OP-IDM looking for first-  
quadrant drain current  
First-quadrant drain  
current  
Negative VDS due to  
third-quadrant drain  
current  
OP-IDM locks FET off  
Power  
Up  
Exit OTSD  
9-6. Operational Ideal-Diode Mode (OP-IDM) State Machine  
1. A new OP-IDM cycle begins in OP-IDM state #1 after the IN pin goes low in OP-IDM state #5. OP-IDM turns  
off the GaN FET in OP-IDM state #1. OP-IDM monitors the GaN FET drain voltage, looking for a positive  
drain voltage to know it can now start looking for a ZVS event. After a positive GaN FET drain voltage is  
detected, the device moves to OP-IDM state #2.  
2. OP-IDM keeps the GaN FET off in OP-IDM state #2. OP-IDM continues monitoring the GaN FET drain  
voltage. But this time it is looking for a negative drain voltage which means third-quadrant current is flowing  
after a ZVS event. This is also the starting state when the device powers up or exits OTSD. After a negative  
GaN FET drain voltage is detected, the device moves to OP-IDM state #3.  
3. OP-IDM turns on the GaN FET in OP-IDM state #3. OP-IDM monitors the drain current in this state. Ideally,  
the device simply stays in this state until IN goes high. The drain current is monitored to protect against an  
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unexpected shoot-through current event. If first-quadrant drain current is detected, the device moves to OP-  
IDM state #4.  
4. OP-IDM locks the GaN FET off in OP-IDM state #4. The GaN FET only turns back on when the IN pin goes  
high.  
5. The device moves to OP-IDM state #5 from any other state when the IN pin goes high. The GaN FET is  
commanded on in OP-IDM state #5. OP-IDM is idle in this state. A new OP-IDM switching cycle begins when  
IN goes low moving the device into OP-IDM state #1.  
OP-IDM can only turn on the GaN FET once per IN cycle. If an unexpected shoot-through current is detected  
between OP-IDM turning on the GaN FET and the IN pin going high, OP-IDM locks the GaN FET off for the  
remainder of the IN cycle.  
Understand that the OP-IDM function turns on the GaN FET, after IN goes low, if it sees a positive drain voltage  
followed by a negative drain voltage. A design using the LMG3425R030 must be analyzed for any situations  
where this sequence of events creates a shoot-through current event. The analysis must include all power  
system corner cases including start-up, shutdown, no load, overload, and fault events. Note that discontinuous  
mode conduction (DCM) operation can easily create an OP-IDM shoot-through current event when the ringing at  
the end of a DCM cycle triggers OP-IDM to turn on the GaN FET.  
Overtemperature-Shutdown Ideal-Diode Mode  
Overtemperature-shutdown ideal-diode mode (OTSD-IDM) is implemented in all devices in the LMG342xR050  
family. As explained in Overtemperature Shutdown, ideal-diode mode provides the best GaN FET protection  
when the GaN FET is overheating.  
OTSD-IDM accounts for all, some, or none of the power system operating when OTSD-IDM is protecting the  
GaN FET. The power system may not have the capability to shut itself down, in response to the LMG342xR050  
asserting the FAULT pin in a GaN OTSD event, and just continue to try to operate. Parts of the power system  
can stop operating due to any reason such as a controller software bug or a solder joint breaking or a device  
shutting off to protect itself. At the moment of power system shutdown, the power system stops providing gate  
drive signals but the inductive elements continue to force current flow while they discharge.  
The OTSD-IDM state machine is shown in 9-7. Each state is assigned a state number in the upper right side  
of the state box. The OTSD-IDM state machine has a similar structure to the OP-IDM state machine. Similar  
states use the same state number.  
1
FET OFF  
OTSD-IDM waiting for IN  
falling-edge blank time to  
expire  
IN falling-edge blank  
time expired  
IN falling edge  
IN falling edge  
First-quadrant drain  
current  
2
3
FET OFF  
FET ON  
OTSD-IDM looking for negative  
VDS  
OTSD-IDM looking for first-  
quadrant drain current  
Negative VDS due to  
third-quadrant drain  
current  
Enter OTSD  
9-7. Overtemperature-Shutdown Ideal-Diode Mode (OTSD-IDM) State Machine  
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1. The LMG342xR050 GaN FET always goes to state #1 if a falling edge is detected on the IN pin. OTSD-IDM  
turns off the GaN FET in OTSD-IDM state #1. OTSD-IDM is waiting for the IN falling edge blank time to  
expire. This time gives the opposite-side FET time to switch to create a positive drain voltage. After the blank  
time expires, the device moves to OTSD-IDM state #2.  
2. For OTSD-IDM state #2, OTSD-IDM keeps the GaN FET off if it is coming from OTSD-IDM state #1 and  
turns the GaN FET off if it is coming from OTSD-IDM state #3. OTSD-IDM is monitoring the GaN FET drain  
voltage in OP-IDM state #2. It is looking for a negative drain voltage which means third-quadrant current is  
flowing. This is also the starting state when the device enters OTSD. After a negative GaN FET drain voltage  
is detected, the device moves to OTSD-IDM state #3  
3. OP-IDM turns on the GaN FET in OTSD-IDM state #3. OP-IDM monitors the drain current in this state. If  
first-quadrant drain current is detected, the device moves to OP-IDM state #2.  
State #1 is used to protect against shoot-through current in a similar manner to OP-IDM state #1. The difference  
is that state #1 in the OTSD-IDM state machine simply waits for a fixed time period before proceeding to state  
#2. The fixed time period is to give the opposite-side switch time to switch and create a positive drain voltage. A  
fixed time is used to avoid a stuck condition for cases where a positive drain voltage is not created.  
State #1 will help protect against shoot-through currents if the converter continues switching when the  
LMG342xR050 enters OTSD. Meanwhile, if the converter initiates switching with the LMG342xR050 already in  
OTSD, shoot-through current protection can be obtained by switching the OTSD device first to force it to  
progress though state #1. For example, the synchronous rectifier in a boost PFC can go into OTSD during initial  
input power application as the inrush current charges the PFC output cap. A shoot-through current event can be  
avoided if converter switching begins by switching the synchronous rectifier FET before switching the boost PFC  
FET.  
If there is no IN signal, the state machine only moves between states #2 and #3 as a classic ideal-diode mode  
state machine. This allows all the inductive elements to discharge, when the power system shuts off, with  
minimum discharge stress created in the GaN FET.  
Note that the OTSD-IDM state machine has no protection against repetitive shoot-through current events. There  
are degenerate cases, such as the LMG342xR050 losing its IN signal during converter operation, which can  
expose the OTSD-IDM to repetitive shoot-through current events. There is no good solution in this scenario. If  
OTSD-IDM did not allow repeated shoot-thru current events, the GaN FET would instead be exposed to  
excessive off-state third-quadrant losses.  
9.4 Start Up Sequence  
9-8 shows the start up sequence of LMG342xR050.  
Time interval A: VDD starts to build up. FAULT signal is initially pulled low.  
Time interval B: After VDD passes the UVLO threshold VVDD,T+(UVLO), both LDO5V and VNEG start to built up. In a  
typical case where CLDO5V = 100 nF and CVNEG = 2.2 μF, LDO5V reaches its UVLO thresold earlier than VNEG  
.
The start-up time may vary if different capacitors are utilized. If VDD has some glitches and falls below UVLO  
threshold VVDD,T-(UVLO) in this time interval, LDO5V and VNEG will stop building up and only resume when VDD  
goes above VVDD,T+(UVLO) again. A longer start-up time is expected in this case.  
Time interval C: After LDO5V and VNEG both reach their thresholds, the FAULT signal is cleared (pulled high)  
and the device is able to switch following the IN pin signal.  
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VVDD,T+(UVLO)  
VDD  
VNEG  
VLDO5V  
t(start)  
FAULT  
(A)  
(B)  
(C)  
9-8. Start Up Timing Diagram  
9.5 Safe Operation Area (SOA)  
9.5.1 Safe Operation Area (SOA) - Repetitive SOA  
The allowed repetitive SOA for the LMG342xR050 (7-12) is defined by the peak drain current (IDS) and the  
drain to source voltage (VDS) of the device during turn on. The peak drain current during switching is the sum of  
several currents going into drain terminal: the inductor current (Iind); the current required to charge the COSS of  
the other GaN device in the totem pole; and the current required to charge the parasitic capacitance (Cpar) on  
the switching node. 145 pF is used as an average COSS of the device during switching. The parasitic  
capacitance on the switch node may be estimated by using the overlap capacitance of the PCB. A boost  
topology is used for the SOA testing. The circuit shown in 9-9 is used to generate the SOA curve in 7-12.  
For reliable operation, the junction temperature of the device must also be limited to 125 °C. The IDS of 7-12  
can be calculated by:  
IDS = Iind + (145 pF + Cpar) * Drain slew rate at peak current  
where drain slew rate at the peak current is estimated between 70 percent and 30 percent of the bus voltage,  
and Cpar is the parasitic board capacitance at the switched node.  
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Q1,Q2:  
LMG342xR050  
D
Q1  
GaN  
FAULT  
IN  
RDRV  
Vbus  
480 V  
L
Temp, Current  
L
O
A
D
Cout  
S
D
Q2  
Iind  
Cpar  
Vin  
GaN  
FAULT  
50 pF  
IN  
RDRV  
Temp, Current  
S
9-9. Circuit Used for SOA Curve  
9.6 Device Functional Modes  
The device has one mode of operation that applies when operated within the Recommended Operating  
Conditions.  
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10 Application and Implementation  
备注  
以下应用部分中的信息不属TI 器件规格的范围TI 不担保其准确性和完整性。TI 的客 户应负责确定  
器件是否适用于其应用。客户应验证并测试其设计以确保系统功能。  
10.1 Application Information  
The LMG342xR050 is a power IC targeting hard-switching and soft-switching applications operating up to 480-V  
bus voltages. GaN devices offer zero reverse-recovery charge enabling high-frequency, hard-switching in  
applications like the totem-pole PFC. Low Qoss of GaN devices also benefits soft-switching converters, such as  
the LLC and phase-shifted full-bridge configurations. As half-bridge configurations are the foundation of the two  
mentioned applications and many others, this section describes how to use the LMG342xR050 in a half-bridge  
configuration.  
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10.2 Typical Application  
ISO_12V_L  
R2 DNP  
2.05  
PGND  
i
D1  
VHV  
i
HVBUS  
U1  
VHV  
GB01SLT06-214  
ISO_12V_H  
5V_H  
i
R1  
0
46  
53  
1
U1NC1  
VDD  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
LMG342x Half-Bridge GaN Daughter Card  
2
3
LDO5V  
VNEG_H  
4
C1  
10uF 0.22µF  
C2  
SW  
5
C3  
D6  
42  
41  
6
VNEG  
VNEG  
5V_H  
7
16V  
25V  
2.2uF  
AGND  
SW  
8
20k 100V/ns  
70k 50V/ns  
9
U3  
DNP R3  
0
SW  
43  
10  
11  
12  
13  
14  
15  
16  
BBSW  
RDRV  
IN  
SDEM20161T-4R7MS  
RDRV_H  
52  
15  
8
2
L1  
GND2  
GND2  
GND1  
GND1  
R5  
9
SW  
INGND  
i
SW  
20.0k  
5V_H  
C7  
50V  
100pF  
C5  
22pF  
10  
11  
12  
13  
14  
16  
7
6
5
4
3
1
SW  
5V  
EN2  
EN1  
OUTD  
INC  
R6  
300  
IN_H  
U1NC16  
47  
i
VHV  
R7  
Top_FET_PWM  
Have R6 close to GaN FET  
IND  
49.9  
R8  
R9  
Top_FET_FAULT  
300  
TEMP_H  
FAULT_H  
OC_H  
U1NC17  
i
51  
48  
50  
17  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
28  
29  
30  
31  
32  
33  
34  
35  
36  
37  
38  
39  
40  
OUTC  
OUTB  
OUTA  
VCC2  
TEMP  
FAULT  
OC  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
VSWNET  
SW  
C6  
68pF  
Top_FET_OC  
300  
INB  
C24 C25  
68pF 68pF  
Top_FET_TEMP  
5V  
INA  
5V_H  
VCC1  
AGND  
AGND AGND  
C26  
1uF  
C10  
0.1uF  
PGND  
TP3  
ISO7741FDBQR  
SW  
AGND  
TP4  
PGND  
TP6  
SW  
PGND  
HV  
TP5  
TH1  
TH2  
TH3  
TH4  
SW  
44SW  
45  
VSWNET  
i
GND  
GND  
GND  
GND  
PAD  
Power Connector  
HVBUS  
49  
U1NC54  
54  
55  
i
VSWNET  
HS push-pin  
LMG342x  
VSWNET  
i
PGND  
U2  
12V  
ISO_12V_L  
C11  
10uF  
R10  
U2NC1  
46  
53  
1
VDD  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
DRAIN  
i
VSWNET  
5V_L  
2
0
DNP  
3
INGND  
i
LDO5V  
TSW-106-08-G-D-RA  
J1  
VNEG_L  
4
C12  
0.22µF  
5
C13  
Bot_FET_PWM  
Bot_FET_FAULT  
Bot_FET_OC  
1
3
2
Top_FET_TEMP  
Top_FET_OC  
Top_FET_FAULT  
Top_FET_PWM  
PGND  
42  
41  
6
20k 100V/ns  
70k 50V/ns  
VNEG  
VNEG  
4
AGND  
5V_L  
7
R17  
25V  
2.2uF  
5
6
DNP  
PGND  
8
TP1  
Bot_FET_TEMP  
7
8
9
20.0k  
9
11  
10  
12  
AGND  
U4  
R12  
DNP  
PGND  
43  
10  
11  
12  
13  
14  
15  
5016  
BBSW  
RDRV  
IN  
C14  
68pF  
Q1  
MGSF1N02LT1G  
R14  
20.0k  
0
SDEM20161T-4R7MS  
ISO7762FQDBQRQ1  
1
L2  
12V  
5V  
C15  
0.022µF  
C16  
0.022µF  
C17  
0.022µF  
C18  
0.022µF  
C19  
0.1uF  
C20  
0.1uF  
C21  
0.1uF  
C38  
0.1uF  
9
10  
11  
12  
13  
14  
15  
16  
8
PGND  
R18  
10.0  
GND2  
GND1  
PGND  
52  
AGND  
AGND  
Top_FET_FAULT  
C8  
50V  
100pF  
7
6
5
4
3
2
1
INF  
OUTF  
OUTE  
IND  
C23  
22pF  
PGND  
R15  
Bot_FET_PWM  
IN_L 47  
16 U2NC16  
INE  
i
i
VSWNET  
PGND  
49.9  
R16  
300  
Bot_FET_FAULT  
Bot_FET_OC  
FAULT_L  
Have R15 close to GaN FET  
OUTD  
OUTC  
OUTB  
OUTA  
VCC2  
TEMP_L 51  
17 U2NC17  
TEMP  
FAULT  
OC  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
SOURCE  
OC_L  
TEMP_L  
INA  
18  
19  
20  
21  
22  
23  
24  
25  
26  
27  
28  
29  
30  
31  
32  
33  
34  
35  
36  
37  
38  
39  
40  
INC  
FAULT_L  
48  
Bot_FET_TEMP  
INB  
OC_L  
50  
OUTA  
INA  
5V  
5V_L  
TP10  
AGND  
TP11  
AGND  
TP2  
PGND  
VCC1  
C9  
1uF  
C27  
0.1uF  
PGND  
AGND  
TP8  
Top_FET_FAULT  
TP9  
Bot_FET_FAULT  
i
PGND  
PGND  
44PGND  
45  
GND  
GND  
GND  
GND  
PAD  
49  
U2NC54  
54  
i
PGND  
55  
LMG342x  
10-1. Typical Half-Bridge Application  
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10.2.1 Design Requirements  
This design example is for a hard-switched boost converter which is representative of PFC applications. 10-1  
shows the system parameters for this design.  
10-1. Design Parameters  
DESIGN PARAMETER  
Input voltage  
EXAMPLE VALUE  
200 VDC  
400 VDC  
20 A  
Output voltage  
Input (inductor) current  
Switching frequency  
100 kHz  
10.2.2 Detailed Design Procedure  
In high-voltage power converters, circuit design and PCB layout are essential for high-performance power  
converters. As designing a power converter is out of the scope of this document, this data sheet describes how  
to build well-behaved half-bridge configurations with the LMG342xR050.  
10.2.2.1 Slew Rate Selection  
The slew rate of LMG342xR050 can be adjusted between approximately 20 V/ns and 150 V/ns by connecting a  
resistor, RRDRV, from the RDRV pin to GND. The RDRV pin is a high-impedance node if a large RRDRV resistor is  
used. Therefore it can be susceptible to coupling from the drain or other fast-slewing high-voltage nodes if it  
isnt well-shielded. This will manifest itself as an unstable switching dv/dt and in extreme cases transient faults  
due to the RDRV being detected as open. Shielding the pin in the layout should be a priority, however if this  
coupling is still a problem, a cap of up to 1nF from RDRV to GND can be added to stabilize the pin voltage.  
The slew rate affects GaN device performance in terms of:  
Switching loss  
Voltage overshoot  
Noise coupling  
EMI emission  
Generally, high slew rates provide low switching loss, but high slew rates can also create higher voltage  
overshoot, noise coupling, and EMI emissions. Following the design recommendations in this data sheet helps  
mitigate the challenges caused by a high slew rate. The LMG342xR050 offers circuit designers the flexibility to  
select the proper slew rate for the best performance of their applications.  
10.2.2.1.1 Start-Up and Slew Rate With Bootstrap High-Side Supply  
Using a bootstrap supply introduces additional constraints on the start-up of the high-side LMG342xR050. Prior  
to powering up, the GaN device operates in cascode mode with reduced performance. In some circuits, a proper  
slew rate can be required for the start-up of a bootstrap-supplied half-bridge configuration.  
10.2.2.2 Signal Level-Shifting  
In half-bridges, high-voltage level shifters or digital isolators must be used to provide isolation for signal paths  
between the high-side device and control circuit. Using an isolator is optional for the low-side device. However,  
using and isolator equalizes the propagation delays between the high-side and low-side signal paths, and  
provides the ability to use different grounds for the GaN device and the controller. If an isolator is not used on the  
low-side device, the control ground and the power ground must be connected at the device and nowhere else on  
the board. For more information, see Layout Guidelines. With fast-switching devices, common ground  
inductance can easily cause noise issues without the use of an isolator.  
Choosing a digital isolator for level-shifting is important for improvement of noise immunity. As GaN device can  
easily create high dv/dt, > 50 V/ns, in hard-switching applications, TI highly recommends to use isolators with  
high common-mode transient immunity (CMTI) and low barrier capacitance. Isolators with low CMTI can easily  
generate false signals, which could cause shoot-through. The barrier capacitance is part of the isolation  
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capacitance between the signal ground and power ground, which is in direct proportion to the common mode  
current and EMI emission generated during the switching. Additionally, TI strongly encourages to select isolators  
which are not edge-triggered. In an edge-triggered isolator, a high dv/dt event can cause the isolator to flip states  
and cause circuit malfunction.  
Generally, ON/OFF keyed isolators with default output low are preferred, such as the TI ISO77xxF series.  
Default low state ensures the system will not shoot-through when starting up or recovering from fault events. As  
a high CMTI event would only cause a very short (a few nanoseconds) false pulse, TI recommends a low pass  
filter, like 300 Ωand 22 pF R-C filter, to be placed at the driver input to filter out these false pulses.  
10.2.2.3 Buck-Boost Converter Design  
10-2 and 10-3 show the buck-boost converter efficiency versus load current with different inductors and  
peak current modes. A minimum inductance value of 3 µH is preferred for the buck-boost converter so that the  
di/dt across the inductor is not too high. This leaves enough margin for the control loop to respond. As a result,  
the maximum di/dt of the inductor is limited to 6 A/µs. On the other hand, large inductance also limits the  
transient response for stable output voltage, and it is preferred to have inductors less than 10 µH.  
85  
80  
75  
70  
LBBSW = 3.3 H  
LBBSW = 4.7 H  
65  
60  
55  
50  
LBBSW = 10 H  
0
10  
20  
30  
40  
50  
60  
70  
80  
90  
Buck-Boost Load Current (mA)  
VDD = 12 V;  
TJ = 25 °C.  
VDD = 12 V; TJ = 25 °C.  
10-3. Buck-Boost Efficiency vs Load when  
10-2. Buck-Boost Efficiency vs Load when  
IBBSW,PK = IBBSW,PK(high)  
IBBSW,PK = IBBSW,PK(low)  
10.2.3 Application Curves  
VDS (50 V/div)  
ID (2.5 A/div)  
VDS (50 V/div)  
ID (1.25 A/div)  
VOUT = 400V  
IL = 5 A  
RDRV = 40 kW  
VBUS = 400 V  
IL = 5 A  
RDRV = 40 kW  
Time (5 ns/div)  
Time (5 ns/div)  
D006  
D007  
10-4. Turn-On Waveform in Application Example 10-5. Turn-Off Waveform in Application Example  
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10.3 Do's and Don'ts  
The successful use of GaN devices in general, and LMG342xR050 in particular, depends on proper use of the  
device. When using the LMG342xR050, DO:  
Read and fully understand the data sheet, including the application notes and layout recommendations.  
Use a four-layer board and place the return power path on an inner layer to minimize power-loop inductance.  
Use small, surface-mount bypass and bus capacitors to minimize parasitic inductance.  
Use the proper size decoupling capacitors and locate them close to the IC as described in Layout Guidelines.  
Use a signal isolator to supply the input signal for the low-side device. If not, ensure the signal source is  
connected to the signal GND plane which is tied to the power source only at the LMG342xR050 IC.  
Use the FAULT pin to determine power-up state and to detect overcurrent and overtemperature events and  
safely shut off the converter.  
To avoid issues in your system when using the LMG342xR050, DON'T:  
Use a single-layer or two-layer PCB for the LMG342xR050 as the power-loop and bypass capacitor  
inductances is excessive and prevent proper operation of the IC.  
Reduce the bypass capacitor values below the recommended values.  
Allow the device to experience drain transients above 600 V as they can damage the device.  
Allow significant third-quadrant conduction when the device is OFF or unpowered, which can cause  
overheating. Self-protection features cannot protect the device in this mode of operation.  
Ignore the FAULT pin output.  
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11 Power Supply Recommendations  
The LMG342xR050 only requires an unregulated VDD power supply from 7.5 V to 18 V. The low-side supply can  
be obtained from the local controller supply. The supply of the high-side device must come from an isolated  
supply or a bootstrap supply.  
11.1 Using an Isolated Power Supply  
Using an isolated power supply to power the high-side device has the advantage that it works regardless of  
continued power-stage switching or duty cycle. Using an isolated power supply can also power the high-side  
device before power-stage switching begins, eliminating the power-loss concern of switching with an unpowered  
LMG342xR050 (see Start-Up and Slew Rate With Bootstrap High-Side Supply for details). Finally, a properly-  
selected isolated supply introduces less parasitics and reduces noise coupling.  
The isolated supply can be obtained with a push-pull converter, a flyback converter, a FlyBuckconverter, or an  
isolated power module. When using an unregulated supply, the input of LMG342xR050 must not exceed the  
maximum supply voltage. A 16-V TVS diode can be used to clamp the VDD voltage of LMG342xR050 for  
additional protection. Minimizing the inter-winding capacitance of the isolated power supply or transformer is  
necessary to reduce switching loss in hard-switched applications. Furthermore, capacitance across the isolated  
bias supply inject high currents into the signal-ground of the LMG342xR050 and can cause problematic ground-  
bounce transients. A common-mode choke can alleviate most of these issues.  
11.2 Using a Bootstrap Diode  
In half-bridge configuration, a floating supply is necessary for the high-side device. To obtain the best  
performance of LMG342xR050, Ti highly recommends Using an Isolated Power Supply. A bootstrap supply can  
be used with the recommendations of this section.  
In applications like a boost converter, the low side LMG342xR050 always start switching while high side  
LMG342xR050 is unpowered. If the low side is adjusted to achieve very high slew rate before the high side bias  
is fully settled, there can be unintentional turn-on at the high side due to parasitic coupling at high slew rate. The  
start-up slew rate must be slowed down to 20 V/ns by changing the resistance of RDRV pin of the low side. This  
slow down can be achieved by controlling the low side RDRV resistance with the high side FAULT as given in 图  
10-1.  
11.2.1 Diode Selection  
The LMG342xR050 offers no reverse-recovery charge and very limited output charge. Hard-switching circuits  
using the LMG342xR050 also exhibit high voltage slew rates. A compatible bootstrap diode must not introduce  
high output charge and reverse-recovery charge.  
A silicon carbide diode, like the GB01SLT06-214, can be used to avoid reverse-recovery effects. The SiC diode  
has an output charge of 3 nC. Althought there is additional loss from its output charge, it does not dominate the  
losses of the switching stage.  
11.2.2 Managing the Bootstrap Voltage  
In a synchronous buck or other converter where the low-side switch occasionally operates in third-quadrant, the  
bootstrap supply charges through a path that includes the third-quadrant voltage drop of the low-side  
LMG342xR050 during the dead time as shown in 11-1. This third-quadrant drop can be large, which can over-  
charge the bootstrap supply in certain conditions. The VDD supply of LMG342xR050 must be kept below 18 V.  
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DRAIN  
VDD  
VF  
SOURCE  
+
œ
DRAIN  
VDD  
VF  
SOURCE  
11-1. Charging Path for Bootstrap Diode  
As shown in 11-2, the recommended bootstrap supply includes a bootstrap diode, a series resistor, and a 16-  
V TVS or zener diode in parallel with the VDD bypass capacitor to prevent damaging the high-side  
LMG342xR050. The series resistor limits the charging current at start-up and when the low-side device is  
operating in third-quadrant mode. This resistor must be selected to allow sufficient current to power the  
LMG342xR050 at the desired operating frequency. At 100-kHz operation, TI recommends a value of  
approximately 2 . At higher frequencies, this resistor value must be reduced or the resistor omitted entirely to  
ensure sufficient supply current.  
DRAIN  
+12 V  
VDD  
VF  
SOURCE  
11-2. Suggested Bootstrap Regulation Circuit  
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12 Layout  
12.1 Layout Guidelines  
The layout of the LMG342xR050 is critical to its performance and functionality. Because the half-bridge  
configuration is typically used with these GaN devices, layout recommendations are considered with this  
configuration. A four-layer or higher layer count board is required to reduce the parasitic inductances of the  
layout to achieve suitable performance.  
12.1.1 Solder-Joint Reliability  
Large QFN packages can experience high solder-joint stress. TI recommends several best practices to ensure  
solder-joint reliability. First, the instructions for the NC1 and NC2 anchor pins found in 6-1 must be followed.  
Second, all the LMG342xR050 board solder pads must be non-solder-mask defined (NSMD) as shown in the  
land pattern example in Mechanical, Packaging, and Orderable Information. Finally, any board trace connected  
to an NSMD pad must be less than 2/3 the width of the pad on the pad side where it is connected. The trace  
must maintain this 2/3 width limit for as long as it is not covered by solder mask. After the trace is under solder  
mask, there are no limits on the trace dimensions. All these recommendations are followed in the Layout  
Example.  
12.1.2 Power-Loop Inductance  
The power loop, comprising the two devices in the half bridge and the high-voltage bus capacitance, undergoes  
high di/dt during switching events. By minimizing the inductance of this loop, ringing and electro-magnetic  
interference (EMI) can be reduced, as well as reducing voltage stress on the devices.  
Place the power devices as close as possible to minimize the power-loop inductance. The decoupling capacitors  
are positioned in line with the two devices. They can be placed close to either device. In Layout Examples, the  
decoupling capacitors are placed on the same layer as the devices. The return path (PGND in this case) is  
located on second layer in close proximity to the top layer. By using inner layer and not bottom layer, the vertical  
dimension of the loop is reduced, thus minimizing inductance. A large number of vias near both the device  
terminal and bus capacitance carries the high-frequency switching current to inner layer while minimizing  
impedance.  
The power loop inductance can be estimated based on the ringing frequency fring of the drain-source voltage  
switching waveform based on the following equation  
1
L
=
(1)  
pl  
2
2
4π f  
C
ring ring  
where Cring is equal to COSS at the bus voltage (refer to 7-8 for the typical value) plus the drain-source  
parasitic capacitance from the board and load inductor or transformer.  
As the parasitic capacitance of load components is hard to character, it's recommended to capture the VDS  
switching waveform without load components to estimate the power loop inductance. Typically, the power loop  
inductance of the Layout Example is around 2.5 nH.  
12.1.3 Signal-Ground Connection  
The LMG342xR050's SOURCE pin is internally connected to GND pins of the power IC, the signal-ground  
reference. Local signal-ground planes must be connected to GND pins with low impedance star connection. In  
addition, the return path for the passives associated to the driver (for example, bypass capacitance) must be  
connected to the GND pins. In Layout Example, local signal-ground planes are located on second layer to act as  
the return path for the local circuitry. The local signal-ground planes are not connected to the high-current  
SOURCE pins except the star connection at GND pins.  
12.1.4 Bypass Capacitors  
The gate drive loop impedance must be minimized to obtain good performance. Although the gate driver is  
integrated on package, the bypass capacitance for the driver is placed externally. As the GaN device is turned  
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off to a negative voltage, the impedance of the path to the external VNEG capacitor is included in the gate drive  
loop. The VNEG capacitor must be placed close to VNEG and GND pins.  
The VDD pin bypass capacitors, C1 and C11, must also be placed close to the VDD pin with low impedance  
connections.  
12.1.5 Switch-Node Capacitance  
GaN devices have very low output capacitance and switch quickly with a high dv/dt, yielding very low switching  
losses. To preserve this low switching losses, additional capacitance added to the output node must be  
minimized. The PCB capacitance at the switch node can be minimized by following these guidelines:  
Minimize overlap between the switch-node plane and other power and ground planes.  
Make the GND return path under the high-side device thinner while still maintaining a low-inductance path.  
Choose high-side isolator ICs and bootstrap diodes with low capacitance.  
Place the power inductor as close to the GaN device as possible.  
Power inductors must be constructed with a single-layer winding to minimize intra-winding capacitance.  
If a single-layer inductor is not possible, consider placing a small inductor between the primary inductor and  
the GaN device to effectively shield the GaN device from the additional capacitance.  
If a back-side heat-sink is used, use the least amount of area of the switch-node copper coverage on the  
bottom copper layer to improve the thermal dissipation.  
12.1.6 Signal Integrity  
The control signals to the LMG342xR050 must be protected from the high dv/dt caused by fast switching.  
Coupling between the control signals and the drain can cause circuit instability and potential destruction. Route  
the control signals (IN, FAULT and OC) over a ground plane placed on an adjacent layer. In Layout Example, for  
example, all the signals are routed on layers close to the local signal ground plane.  
Capacitive coupling between the traces for the high-side device and the static planes, such as PGND and  
HVBUS, could cause common mode current and ground bounce. The coupling can be mitigated by reducing  
overlap between the high-side traces and the static planes. For the high-side level shifter, ensure no copper from  
either the input or output side extends beneath the isolator or the CMTI of the device can be compromised.  
12.1.7 High-Voltage Spacing  
Circuits using the LMG342xR050 involve high voltage, potentially up to 600 V. When laying out circuits using the  
LMG342xR050, understand the creepage and clearance requirements for the application and how they apply to  
the GaN device. Functional (or working) isolation is required between the source and drain of each transistor,  
and between the high-voltage power supply and ground. Functional isolation or perhaps stronger isolation (such  
as reinforced isolation) can be required between the input circuitry to the LMG342xR050 and the power  
controller. Choose signal isolators and PCB spacing (creepage and clearance) distances which meet your  
isolation requirements.  
If a heat sink is used to manage thermal dissipation of the LMG342xR050, ensure necessary electrical isolation  
and mechanical spacing is maintained between the heat sink and the PCB.  
12.1.8 Thermal Recommendations  
The LMG342xR050 is a lateral device grown on a Si substrate. The thermal pad is connected to the source of  
device. The LMG342xR050 can be used in applications with significant power dissipation, for example, hard-  
switched power converters. In these converters, cooling using just the PCB can not be sufficient to keep the part  
at a reasonable temperature. To improve the thermal dissipation of the part, TI recommends a heat sink is  
connected to the back of the PCB to extract additional heat. Using power planes and numerous thermal vias, the  
heat dissipated in the LMG342xR050 can be spread out in the PCB and effectively passed to the other side of  
the PCB. A heat sink can be applied to bare areas on the back of the PCB using an thermal interface material  
(TIM). The solder mask from the back of the board underneath the heat sink can be removed for more effective  
heat removal.  
Refer to the High Voltage Half Bridge Design Guide for LMG3410 Smart GaN FET application note for more  
recommendations and performance data on thermal layouts.  
Copyright © 2022 Texas Instruments Incorporated  
38  
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12.2 Layout Examples  
Correct layout of the LMG342xR050 and its surrounding components is essential for correct operation. The  
layouts shown here reflect the GaN device schematic in 10-1. These layouts are shown to produce good  
results and is intended as a guideline. However, it can be possible to obtain acceptable performance with  
alternate layout schemes. Additionally, please refer to the land pattern example in Mechanical, Packaging, and  
Orderable Information for the latest recommended PCB footprint of the device.  
The the top-layer layout and mid-layer layout are shown. The layouts are zoomed in to the LMG342xR050 U1  
and U2 component placements. The mid-layer layout includes the outlines of the top level components to assist  
the reader in lining up the top-layer and mid-layer layouts.  
Copyright © 2022 Texas Instruments Incorporated  
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LMG3422R050, LMG3425R050  
ZHCSNN4B OCTOBER 2020 REVISED MAY 2022  
www.ti.com.cn  
12-1. Half-Bridge Top-Layer Layout  
12-2. Half-Bridge Mid-Layer Layout  
Copyright © 2022 Texas Instruments Incorporated  
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LMG3422R050, LMG3425R050  
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13 Device and Documentation Support  
13.1 Documentation Support  
13.1.1 Related Documentation  
Texas Instruments, High Voltage Half Bridge Design Guide for LMG3410 Smart GaN FET application note.  
Texas Instruments, A New Approach to Validate GaN FET Reliability to Power-line Surges Under Use-  
conditions.  
13.2 接收文档更新通知  
要接收文档更新通知请导航至 ti.com 上的器件产品文件夹。点击订阅更新 进行注册即可每周接收产品信息更  
改摘要。有关更改的详细信息请查看任何已修订文档中包含的修订历史记录。  
13.3 支持资源  
TI E2E支持论坛是工程师的重要参考资料可直接从专家获得快速、经过验证的解答和设计帮助。搜索现有解  
答或提出自己的问题可获得所需的快速设计帮助。  
链接的内容由各个贡献者“按原样”提供。这些内容并不构成 TI 技术规范并且不一定反映 TI 的观点请参阅  
TI 《使用条款》。  
13.4 Trademarks  
FlyBuckis a trademark of Texas Instruments.  
TI E2Eis a trademark of Texas Instruments.  
所有商标均为其各自所有者的财产。  
13.5 Electrostatic Discharge Caution  
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled  
with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.  
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may  
be more susceptible to damage because very small parametric changes could cause the device not to meet its published  
specifications.  
13.6 Export Control Notice  
Recipient agrees to not knowingly export or re-export, directly or indirectly, any product or technical data (as  
defined by the U.S., EU, and other Export Administration Regulations) including software, or any controlled  
product restricted by other applicable national regulations, received from disclosing party under nondisclosure  
obligations (if any), or any direct product of such technology, to any destination to which such export or re-export  
is restricted or prohibited by U.S. or other applicable laws, without obtaining prior authorization from U.S.  
Department of Commerce and other competent Government authorities to the extent required by those laws.  
13.7 术语表  
TI 术语表  
本术语表列出并解释了术语、首字母缩略词和定义。  
14 Mechanical, Packaging, and Orderable Information  
The following pages include mechanical, packaging, and orderable information. This information is the most  
current data available for the designated devices. This data is subject to change without notice and revision of  
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.  
Copyright © 2022 Texas Instruments Incorporated  
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Product Folder Links: LMG3422R050 LMG3425R050  
 
 
 
 
 
 
 
 
 
 
LMG3422R050, LMG3425R050  
ZHCSNN4B OCTOBER 2020 REVISED MAY 2022  
www.ti.com.cn  
PACKAGE OUTLINE  
RQZ0054A-C01  
VQFN - 1 mm max height  
S
C
A
L
E
1
.
1
0
0
PLASTIC QUAD FLATPACK - NO LEAD  
12.1  
11.9  
A
B
PIN 1 ID  
INDEX AREA  
12.1  
11.9  
1.0  
0.8  
C
SEATING PLANE  
0.08 C  
0.05  
0.00  
7.8 0.1  
PKG  
(2.75)  
0.65  
0.55  
54X  
(2.65)  
(0.1) TYP  
27  
17  
4X 0.975  
16  
28  
1.1  
4X  
1.0  
0.1  
C A B  
C
10.2 0.1  
0.05  
2X 8.45  
55  
PKG SYMM  
26X 0.65  
PIN 1 ID  
(45 X 0.3)  
0.45  
0.35  
46X  
0.1  
C A B  
C
0.05  
43  
1
54  
44  
4X (0.25)  
4X (0.2)  
0.65  
0.55  
4X  
2X 1.285  
0.1  
C A B  
16X 0.65  
2X 5.2  
0.05  
C
4X 0.75  
4228230/A 11/2021  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.  
www.ti.com  
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LMG3422R050, LMG3425R050  
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EXAMPLE BOARD LAYOUT  
RQZ0054A-C01  
VQFN - 1 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
(7.8)  
(4.906)  
(2.65)  
(4.449) TYP  
(0.914) TYP  
54X (0.8)  
54  
44  
(0.508) TYP  
43  
4X (1.05)  
1
(
0.2) TYP  
VIA  
(4.572)  
(4.826)  
46X (0.4)  
(10.2)  
55  
PKG SYMM  
(11.6)  
(R0.05) TYP  
42X (0.65)  
4X (0.975)  
28  
16  
17  
27  
4X (0.75)  
2X (2.035)  
(1.25)  
PAD  
4X (0.6)  
PKG  
(11.6)  
LAND PATTERN EXAMPLE  
EXPOSED METAL SHOWN  
SCALE:8X  
0.07 MAX  
ALL AROUND  
METAL EDGE  
EXPOSED  
METAL  
SOLDER MASK  
OPENING  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAIL  
4228230/A 11/2021  
NOTES: (continued)  
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments  
literature number SLUA271 (www.ti.com/lit/slua271).  
5. All pads must be NSMD for mechanical performance, refer to the device datasheet for trace connection recommendations to the pads.  
6. Filling the thermal pad with thermal vias is recommended for thermal performance, refer to the device datasheet. Vias must be filled and  
planarized.  
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LMG3422R050, LMG3425R050  
ZHCSNN4B OCTOBER 2020 REVISED MAY 2022  
www.ti.com.cn  
EXAMPLE STENCIL DESIGN  
RQZ0054A-C01  
VQFN - 1 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
(4.225)  
(1.19) TYP  
50X (0.8)  
54  
4X (0.76)  
44  
1
43  
4X (1)  
48X ( 0.99)  
(1.19) TYP  
(4.165)  
46X (0.4)  
55  
PKG SYMM  
(11.6)  
(R0.05) TYP  
42X (0.65)  
4X (0.975)  
28  
16  
17  
27  
PKG  
4X (0.6)  
4X (0.75)  
2X (2.035)  
(11.6)  
SOLDER PASTE EXAMPLE  
BASED ON 0.125 mm THICK STENCIL  
PRINTED SOLDER COVERAGE BY AREA UNDER PACKAGE  
PADS 1, 16, 28 & 43: 90%  
PAD 55: 60%  
SCALE:8X  
4228230/A 11/2021  
NOTES: (continued)  
7. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
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Product Folder Links: LMG3422R050 LMG3425R050  
PACKAGE OPTION ADDENDUM  
www.ti.com  
23-Jun-2023  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
2000  
250  
(1)  
(2)  
(3)  
(4/5)  
(6)  
LMG3422R050RQZR  
LMG3422R050RQZT  
LMG3425R050RQZR  
LMG3425R050RQZT  
XLMG3425R050RQZT  
ACTIVE  
VQFN  
VQFN  
VQFN  
VQFN  
VQFN  
RQZ  
54  
54  
54  
54  
54  
RoHS-Exempt  
& Green  
NIPDAU  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
-40 to 150  
-40 to 150  
-40 to 150  
-40 to 150  
-40 to 150  
LMG3422  
Samples  
Samples  
Samples  
Samples  
Samples  
R050  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
RQZ  
RoHS-Exempt  
& Green  
NIPDAU  
NIPDAU  
NIPDAU  
Call TI  
LMG3422  
R050  
RQZ  
2000  
250  
RoHS-Exempt  
& Green  
LMG3425  
R050  
RQZ  
RoHS-Exempt  
& Green  
LMG3425  
R050  
RQZ  
250  
RoHS &  
Non-Green  
XLMG3425  
R050G10D21  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6)  
Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two  
lines if the finish value exceeds the maximum column width.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
23-Jun-2023  
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information  
provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
3-Jun-2022  
TAPE AND REEL INFORMATION  
REEL DIMENSIONS  
TAPE DIMENSIONS  
K0  
P1  
W
B0  
Reel  
Diameter  
Cavity  
A0  
A0 Dimension designed to accommodate the component width  
B0 Dimension designed to accommodate the component length  
K0 Dimension designed to accommodate the component thickness  
Overall width of the carrier tape  
W
P1 Pitch between successive cavity centers  
Reel Width (W1)  
QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE  
Sprocket Holes  
Q1 Q2  
Q3 Q4  
Q1 Q2  
Q3 Q4  
User Direction of Feed  
Pocket Quadrants  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LMG3422R050RQZR  
LMG3422R050RQZT  
LMG3425R050RQZR  
LMG3425R050RQZT  
VQFN  
VQFN  
VQFN  
VQFN  
RQZ  
RQZ  
RQZ  
RQZ  
54  
54  
54  
54  
2000  
250  
330.0  
180.0  
330.0  
180.0  
24.4  
24.4  
24.4  
24.4  
12.35 12.35  
12.35 12.35  
12.35 12.35  
12.35 12.35  
1.5  
1.5  
1.5  
1.5  
16.0  
16.0  
16.0  
16.0  
24.0  
24.0  
24.0  
24.0  
Q2  
Q2  
Q2  
Q2  
2000  
250  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
3-Jun-2022  
TAPE AND REEL BOX DIMENSIONS  
Width (mm)  
H
W
L
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LMG3422R050RQZR  
LMG3422R050RQZT  
LMG3425R050RQZR  
LMG3425R050RQZT  
VQFN  
VQFN  
VQFN  
VQFN  
RQZ  
RQZ  
RQZ  
RQZ  
54  
54  
54  
54  
2000  
250  
350.0  
213.0  
350.0  
213.0  
350.0  
191.0  
350.0  
191.0  
43.0  
55.0  
43.0  
55.0  
2000  
250  
Pack Materials-Page 2  
重要声明和免责声明  
TI“按原样提供技术和可靠性数据(包括数据表)、设计资源(包括参考设计)、应用或其他设计建议、网络工具、安全信息和其他资源,  
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保。  
这些资源可供使用 TI 产品进行设计的熟练开发人员使用。您将自行承担以下全部责任:(1) 针对您的应用选择合适的 TI 产品,(2) 设计、验  
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您无权使用任何其他 TI 知识产权或任何第三方知识产权。您应全额赔偿因在这些资源的使用中对 TI 及其代表造成的任何索赔、损害、成  
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邮寄地址:Texas Instruments, Post Office Box 655303, Dallas, Texas 75265  
Copyright © 2023,德州仪器 (TI) 公司  

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