TPS92643QPWPRQ1 [TI]

汽车类 3A 同步降压 LED 驱动器 | PWP | 16 | -40 to 125;
TPS92643QPWPRQ1
型号: TPS92643QPWPRQ1
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

汽车类 3A 同步降压 LED 驱动器 | PWP | 16 | -40 to 125

驱动 驱动器
文件: 总39页 (文件大小:2789K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
TPS92643-Q1  
ZHCSQK6 MAY 2022  
TPS92643-Q1 3A 同步降LED 驱动器  
TPS92643-Q1 采用 6.6mm × 5.1mm 热增强型 16 引  
HTSSOP 封装引线间距0.65mm。  
1 特性  
• 符合面向汽车应用AEC-Q100 标准  
器件信息  
封装(1)  
1 40°C 125°C 的工作环境温度范围  
– 器HBM 分类等H1C  
– 器CDM 分类等C5  
封装尺寸标称值)  
器件型号  
TPS92643-Q1  
HTSSOP (16)  
6.60mm × 5.10mm  
(1) 如需了解所有可用封装请参阅产品说明书末尾的可订购产品  
附录。  
• 输入电压范围5.5 V 36 V  
– 启动后工作电压低5.15V  
• 高3A 的连续电流精度4%  
• 自适应导通时间电流控制  
– 低失调高侧电流检测放大器  
– 与陶瓷和铝电容器等任意电容器组合搭配使用时  
均可保持稳定  
RCS  
L
LED+  
COUT  
1
2
16  
SW  
SW  
PGND  
GND  
VIN  
CIN1  
15  
14  
RBST  
CBST  
VIN  
VIN  
3
• 可编程开关频率范围100kHz 2.2MHz  
• 高级调光操作  
BST  
CVCC  
4
5
VCC  
IADJ  
RON  
RUV2  
RUV1  
1000:1 高精PWM 调光  
15:1 高精度模拟调光  
1.4kHz 内部模拟输入PWM 占空比的转换  
• 开关逐周期过流保护  
• 开漏故障指示灯输出  
13  
12  
11  
10  
9
RON  
UDIM  
CSP  
CSN  
FLT  
CCOMP  
6
7
COMP  
AGND  
PWM  
RPWM1  
RNTC  
8
APWM  
LED 短路、开路和电缆线束故障指示  
• 热关断保护  
典型降LED 驱动器应用示意图  
2 应用  
96  
94  
92  
90  
88  
86  
84  
82  
80  
78  
76  
74  
72  
• 前照灯  
• 前雾LED 驱动器模块  
3 说明  
TPS92643-Q1 是一款单片同步降压 LED 驱动器具  
5.5V 36V 宽工作输入电压范围和 40V 容差支  
400ms 时长的负载突降。TPS92643-Q1 基于电感  
器谷值电流检测实现自适应导通时间平均电流模式控  
制。自适应导通时间控制功能可提供近乎恒定的开关频  
频率设置范围为 100kHz 2.2MHz。电感器电流  
检测和闭环反馈功能可在宽输入、输出和环境温度范围  
内实±4% 以上的精度。  
1 LED  
2 LEDs  
3 LEDs  
0
0.3 0.6 0.9 1.2 1.5 1.8 2.1 2.4 2.7  
LED Current (A)  
3
典型效率  
高性能 LED 驱动器可使用模拟调光或 PWM 调光技术  
来单独调制 LED 电流。通过设置 IADJ 电压可获得超  
15:1 范围的线性模拟调光范围。通过使用所需占空  
比直接调制 UDIM 输入引脚或设置 APWM 的模拟电  
压以启用内部模拟至 PWM 转换可实现 LED 电流的  
PWM 调光。。内部 PWM 发生器通过将外部模拟电压  
与内部 1.4kHz 斜坡信号进行比较来实现外部模拟电压  
的转换。  
TPS92643-Q1 包含高级诊断和故障保护功能逐周期  
开关电流限制、自举欠压保护、LED 开路保护、LED  
短路保护和热关断保护。  
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: SLUSCV5  
 
 
 
 
TPS92643-Q1  
ZHCSQK6 MAY 2022  
www.ti.com.cn  
Table of Contents  
7.4 Device Functional Modes..........................................21  
8 Application and Implementation..................................22  
8.1 Application Information............................................. 22  
8.2 Typical Application.................................................... 26  
9 Power Supply Recommendations................................30  
10 Layout...........................................................................31  
10.1 Layout Guidelines................................................... 31  
10.2 Layout Example...................................................... 32  
11 Device and Documentation Support..........................33  
11.1 接收文档更新通知................................................... 33  
11.2 支持资源..................................................................33  
11.3 Trademarks............................................................. 33  
11.4 Electrostatic Discharge Caution..............................33  
11.5 术语表..................................................................... 33  
12 Mechanical, Packaging, and Orderable  
1 特性................................................................................... 1  
2 应用................................................................................... 1  
3 说明................................................................................... 1  
4 Revision History.............................................................. 2  
5 Pin Configuration and Functions...................................3  
6 Specifications.................................................................. 4  
6.1 Absolute Maximum Ratings........................................ 4  
6.2 ESD Ratings............................................................... 4  
6.3 Recommended Operating Conditions.........................4  
6.4 Thermal Information....................................................5  
6.5 Electrical Characteristics.............................................5  
6.6 Typical Characteristics................................................8  
7 Detailed Description......................................................10  
7.1 Overview...................................................................10  
7.2 Functional Block Diagram......................................... 11  
7.3 Feature Description...................................................12  
Information.................................................................... 33  
4 Revision History  
DATE  
REVISION  
NOTES  
May 2022  
*
Initial release.  
Copyright © 2022 Texas Instruments Incorporated  
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ZHCSQK6 MAY 2022  
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5 Pin Configuration and Functions  
SW  
SW  
1
2
3
4
5
6
7
8
16  
15  
14  
13  
12  
11  
10  
9
PGND  
VIN  
BST  
VIN  
VCC  
RON  
UDIM  
CSP  
CSN  
FLT  
IADJ  
COMP  
AGND  
APWM  
5-1. PWP Package, 16-Pin HTSSOP with PowerPAD, Top View  
5-1. Pin Functions  
PIN  
I/O  
DESCRIPTION  
NO.  
NAME  
AGND  
Analog ground. Return for the internal voltage reference and analog circuit. Connect to circuit ground,  
GND, to complete return path.  
7
I
Supply input for high-side MOSFET gate drive circuit. Connect a ceramic capacitor between BST and  
SW pins. An internal diode is connected between VCC and BST pins.  
3
6
BST  
Output of internal transconductance error amplifier. Connect an integral compensation network to  
ensure stability.  
COMP  
CSN  
O
Negative input () of internal rail-to-rail transconductance error amplifier. Connect directly to the  
10  
I
negative node of the LED current sense resistor, RCS  
Positive input (+) of internal rail-to-rail transconductance error amplifier. Connect directly to the positive  
node of the LED current sense resistor, RCS  
.
11  
9
CSP  
FLT  
I
.
O
Open-drain fault indicator. Connect to VCC with a resistor to create an active low fault signal output.  
Analog adjust input. Input below 100 mV disables the output. The analog input can be varied between  
140 mV to 2.4 V to set current reference from 10 mV to 175 mV. Connect a 0.1-μF capacitor from pin  
to AGND.  
5
16  
8
IADJ  
I
PGND  
APWM  
Ground returns for low-side MOSFETs  
External analog to PWM dimming command. The external analog dimming command between 1 V and  
2.45 V is compared to the internal 1.5-kHz triangle waveform to set LED current duty cycle between  
0% and 100%.  
I
On-time programming pin. Connect a resistor to VIN based on the desired pseudo-fixed switching  
frequency.  
13  
RON  
SW  
I
I
Switching output of the regulator. Internally connected to both power MOSFETs. Connect to the power  
inductor.  
1,2  
Undervoltage lockout and external PWM dimming input. Connect to VIN through a resistor divider to  
implement input undervoltage protection. Diode couple external PWM signal to enable dimming. Do  
not float.  
12  
4
UDIM  
VCC  
VIN  
I
O
I
VCC bias supply pin. Locally decouple to AGND using a 2.2-μF to 4.7-μF ceramic capacitor located  
close to the controller.  
Power input and connection to high-side MOSFET drain node. Connect to the power supply and  
bypass capacitors CIN. The path from the VIN pin to the high frequency bypass capacitor and PGND  
must be as short as possible.  
14,15  
PowerPAD  
The AGND and PGND pin must be connected to the exposed PowerPAD for proper operation. This  
PowerPAD must be connected to PCB ground plane using multiple vias for good thermal performance.  
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ZHCSQK6 MAY 2022  
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6 Specifications  
6.1 Absolute Maximum Ratings  
over operating free-air temperature range (unless otherwise noted)(1)  
MIN  
MAX  
36  
UNIT  
V
VIN  
Input Voltage  
0.3  
VIN (< 400 ms)  
40  
V
Bias supply  
VVCC  
5.5  
V
0.3  
voltage, VCC  
BST to SW  
5.5  
41.5  
36  
V
V
0.3  
0.3  
0.5  
0.5  
3.5  
0.5  
0.1  
Boot voltage,  
BST  
BST to GND  
VSW to GND  
V
Switch node  
voltage  
VSW to GND (< 400 ms)  
40  
V
VSW to GND (< 10 ns)  
40  
V
CSP, CSN  
RON  
36  
V
36  
V
IRON  
500  
0.3  
VVIN  
5.5  
5.5  
20  
µA  
mV  
V
V(CSP-CSN)  
Inputs  
0.3  
0.3  
0.1  
0.3  
0.3  
0.5  
3.5  
40  
UDIM to GND  
IADJ  
V
COMP, APWM  
FLT  
V
Outputs  
Ground  
V
PGND to AGND  
PGND to AGND (< 10 ns)  
Junction temperature  
Storage temperature  
0.5  
3.5  
150  
150  
V
V
TJ  
°C  
°C  
Tstg  
40  
(1) Operation outside the Absolute Maximum Ratings may cause permanent device damage. Absolute Maximum Ratings do not imply  
functional operation of the device at these or any other conditions beyond those listed under Recommended Operating Conditions. If  
used outside the Recommended Operating Conditions but within the Absolute Maximum Ratings, the device may not be fully  
functional, and this may affect device reliability, functionality, performance, and shorten the device lifetime.  
6.2 ESD Ratings  
VALUE UNIT  
Human body model (HBM), per AEC Q100-002(1)  
±2000  
±750  
±500  
Corner pins (SW, APWM, FLT and  
V(ESD) Electrostatic discharge  
V
Charged device model (CDM), per  
AEC Q100-011  
PGND)  
Other pins  
(1) AEC Q100-002 indicates that HBM stressing shall be in accordance with the ANSI/ESDA/JEDEC JS-001 specification.  
6.3 Recommended Operating Conditions  
over operating free-air temperature range (unless otherwise noted)  
MIN  
5.5  
8
NOM  
MAX  
UNIT  
V
VVIN  
Input Voltage  
36  
V(CSP-CSN) Sensed inductor current ripple voltage  
mV  
V/µs  
A
dVCSP/dt  
ILED  
CSP slew-rate  
10  
3
LED Current (Continuous)  
Analog PWM Input  
VAPWM  
3
0.3  
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6.3 Recommended Operating Conditions (continued)  
over operating free-air temperature range (unless otherwise noted)  
MIN  
0.3  
0.3  
400  
NOM  
MAX  
VVIN  
18  
UNIT  
VUDIM  
FLT  
fSW  
TA  
Digital PWM Input  
Fault Output  
Switching Frequency  
Ambient temperature  
Junction temperature  
2200  
125  
150  
kHz  
°C  
40  
40  
TJ  
°C  
6.4 Thermal Information  
DEVICE  
THERMAL METRIC(1)  
PKG (HTSSOP)  
UNIT  
PINS  
38.9  
24.3  
19.9  
0.7  
RθJA  
Junction-to-ambient thermal resistance  
Junction-to-case (top) thermal resistance  
Junction-to-board thermal resistance  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
RθJC(top)  
RθJB  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
Junction-to-case (bottom) thermal resistance  
ΨJT  
19.7  
1.7  
ΨJB  
RθJC(bot)  
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application  
report.  
6.5 Electrical Characteristics  
40°C < TJ < 150°C, VIN = 14V, VUDIM = 5V, VIADJ = 2.1V, CVCC = 2.2μF, CBST = 1nF, CCOMP = 1nF, RCS = 100mΩ, RON  
401kΩ, VAPWM = 5V, fSW = 200 kHz  
=
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
INPUT VOLTAGE (VIN)  
VDO  
ISW  
IOP  
LDO dropout voltage  
Input switching current  
Input operating current  
IVCC = 20 mA, VVIN = 5 V  
315  
10  
2
mV  
mA  
mA  
17.6  
4
Not switching, VIADJ = VVCC  
BIAS SUPPLY (VCC)  
VCC(UVLO-RISE) Rising threshold  
VCC(UVLO-FALL) Falling threshold  
VCC(UVLO-HYS)  
VCC rising threshold, VVIN = 8 V  
VCC falling threshold, VVIN = 8 V  
Hysteresis  
4.40  
4.2  
4.58  
V
V
3.9  
200  
5.00  
56  
mV  
V
VCC(REG)  
ICC(LIMIT)  
Regulation voltage  
Supply current Limit  
No Load  
4.75  
45  
5.25  
76  
VVCC = 0 V  
mA  
HIGH-SIDE FET (SW, BOOT)  
RDS(ON-HS)  
VBST(UV)  
VBST(HYS)  
IQ(BST)  
High-side MOSFET on resistance  
ILED = 100 mA  
65  
3.2  
130  
3.47  
240  
325  
mΩ  
V
Bootstrap gate drive UVLO  
V(BST-SW) rising  
2.95  
175  
197  
Bootstrap gate drive UVLO hysteresis  
Bootstrap pin quiescent current  
Hysteresis  
207  
265  
mV  
µA  
VSW = 0V, VUDIM = 0 V, VBOOT = 5 V  
LOW-SIDE FET (SW)  
RDS(ON-LS)  
Low-side MOSFET on resistance  
ILED = 100 mA  
67  
130  
mΩ  
HIGH SIDE FET CURRENT LIMIT  
ILIM(HS)  
High-side current limit threshold  
High-side current sense blanking period  
3.75  
35  
4.80  
60  
5.85  
80  
A
t(HS-BLANK)  
ns  
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6.5 Electrical Characteristics (continued)  
40°C < TJ < 150°C, VIN = 14V, VUDIM = 5V, VIADJ = 2.1V, CVCC = 2.2μF, CBST = 1nF, CCOMP = 1nF, RCS = 100mΩ, RON  
401kΩ, VAPWM = 5V, fSW = 200 kHz  
=
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
LOW SIDE FET CURRENT LIMIT  
ISINK(LS)  
tBLANK  
Sinking current limit  
Blanking time  
2.0  
3.2  
71  
4.3  
A
ns  
ERROR AMPLIFIER (CSP, CSN, COMP)  
VIADJ = VCC, VCSP = 3 V, ICOMP = 0 V  
VIADJ = 2.1 V, VCSP = 3 V, ICOMP = 0 V  
168  
175  
150  
450  
200  
140  
2.45  
440  
3
182  
mV  
mV  
µA/V  
µA  
V(CSP-CSN)  
Current sense threshold  
gM  
Transconductance  
ICOMP(SRC)  
ICOMP(SINK)  
VCOMP(RISE)  
COMP current source capacity  
COMP current sink capacity  
COMP startup threshold  
VIADJ = 2.5 V, V(CSP-CSN) = 0 V  
VIADJ = 150 mV, V(CSP-CSN) = 300 mV  
Rising  
µA  
V
VCOMP(HYS  
EA(BW)  
)
COMP startup comparator hysteresis  
Bandwidth  
mV  
MHz  
nA  
Unity gain bandwidth  
VUDIM = 0 V  
ICOMP(LKG)  
Comp leakage current  
2.5  
VCOMP(RST)  
RCOMP(DCH)  
VCOMP(OV)  
COMP pin reset voltage  
VVCC dropping from 5 V to 0 V  
100  
230  
3.2  
mV  
COMP discharge FET resistance  
COMP overvoltage protection threshold  
Ω
2.9  
V
COMP overvoltage protection  
hysteresis  
VCOMP(OV-HYS)  
60  
mV  
Falling  
Rising  
1.5  
1.6  
V
V
VCSP(SHORT)  
Output short circuit detection threshold  
ANALOG ADJUST INPUT (IADJ)  
VIADJ(CLAMP) IADJ internal clamp voltage  
VIADJ(DIS)  
2.45  
133  
100  
V
Disable threshold voltage  
Disable threshold voltage  
Rising  
Falling  
mV  
mV  
VIADJ(DIS)  
VALLEY CURRENT COMPARATOR  
gM(LV) Level shift amplifier transconductance  
tDEL V(CSP-CSN) falling to gate rising delay  
ON-TIME GENERATOR (RON)  
50  
65  
µA/V  
ns  
80  
tON(MIN)  
Minimum on-time  
81  
96  
150  
336  
0.95  
3.55  
111  
ns  
ns  
ns  
µs  
µs  
VVIN = 14 V, VCSP = 5 V, RON = 35 kΩ  
VVIN = 10 V, VCSP = 8 V, RON = 35 kΩ  
VVIN = 14 V, VCSP = 3 V, RON = 400 kΩ  
VVIN = 10 V, VCSP = 8 V, RON = 400 kΩ  
tON  
Programmed on-time  
MINIMUM OFF-TIME  
tOFF(MIN) Minimum off-time  
V(CSP-CSN) = 0 V, VCOMP = 2.5 V  
76  
6.5  
91  
106  
ns  
PWM DIMMING and PROGRAMMABLE UVLO INPUT (UDIM)  
IUDIM(DO) UDIM source current (UVLO hysteresis) VUDIM > 2.45 V  
10  
2.44  
2.34  
1.22  
1.120  
245  
13  
µA  
V
VUDIM(DO,RISE) Dropout detection rising threshold  
VUDIM(DO,FALL) Dropout detection falling threshold  
VUDIM(EN,RISE) Undervoltage lockout rising threshold  
VUDIM(EN,FALL) Undervoltage lockout falling threshold  
VUDIM rising  
VUDIM falling  
VUDIM rising  
VUDIM falling  
2.54  
2.24  
1.075  
V
1.27  
V
V
tUDIM(RISE)  
tUDIM(FALL)  
UDIM to SW pin rising delay  
UDIM pin SW pin falling delay  
ns  
ns  
105  
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6.5 Electrical Characteristics (continued)  
40°C < TJ < 150°C, VIN = 14V, VUDIM = 5V, VIADJ = 2.1V, CVCC = 2.2μF, CBST = 1nF, CCOMP = 1nF, RCS = 100mΩ, RON  
401kΩ, VAPWM = 5V, fSW = 200 kHz  
=
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
ANALOG TO PWM GENERATOR (APWM)  
fRAMP  
Internal ramp generator frequency  
Internal ramp high threshold  
Internal ramp low threshold  
VUDIM = 5 V  
1.0  
1.5  
2.45  
1.00  
1
1.9  
kHz  
V
VRAMP(HIGH)  
VRAMP(LOW)  
VUDIM = 5 V  
VUDIM = 5 V  
VUDIM = 0 V  
2.60  
0.95  
V
VRAMP(CLAMP) Internal ramp clamp  
V
tAPWM(RISE)  
tAPWM(FALL)  
VAPWM(HYS)  
APWM to SW pin rising delay  
200  
80  
ns  
ns  
mV  
APWM to SW pin falling delay  
Analog to PWM comparator hysteresis  
5
FAULT INDICATION (nFLT)  
R(FLT)  
Fault pin pull-down resistance  
IFLT = 20 mA  
2.5  
5.5  
20  
7
Ω
ms  
µs  
TOC  
Hiccup retry delay time  
TUC(BLANK)  
IFLT(LKG)  
Undercurrent reporting blanking period  
Fault pin leakage current  
100  
nA  
THERMAL SHUTDOWN  
TSD  
Thermal shutdown threshold  
Thermal shutdown hysteresis  
175  
15  
°C  
°C  
TSD(HYS)  
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6.6 Typical Characteristics  
40°C < TJ < 150°C, VIN = 14 V, VUDIM = 5 V, VIADJ = 2.1V , CVCC = 2.2 μF, CBST = 1 nF, CCOMP = 1 nF, RCS = 100 mΩ,  
RON = 401 kΩ, VAPWM = 5 V, fSW = 200 kHz  
5.01  
5.008  
5.006  
5.004  
5.002  
5
120  
110  
100  
90  
80  
4.998  
4.996  
4.994  
4.992  
4.99  
70  
60  
50  
40  
-40 -20  
0
20  
40  
60  
80 100 120 140 160  
-40 -20  
0
20  
40  
60  
80 100 120 140 160  
Temperature (C)  
Temperature (C)  
6-1. VCC Regulation Voltage vs Temperature  
6-2. High-Side MOSFET On Resistance vs Temperature  
5.2  
5.1  
5
120  
110  
100  
90  
4.9  
4.8  
4.7  
4.6  
4.5  
4.4  
4.3  
4.2  
4.1  
4
80  
70  
60  
50  
40  
-40 -20  
0
20  
40  
60  
80 100 120 140 160  
-40 -20  
0
20  
40  
60  
80 100 120 140 160  
Temperature (C)  
Temperature (C)  
6-4. Low-Side MOSFET On Resistance vs Temperature  
6-3. High-Side Current Limit Threshold vs Temperature  
3.375  
3.325  
3.275  
3.225  
3.175  
3.125  
3.075  
3.025  
2.975  
2.925  
2.451  
2.4505  
2.45  
2.4495  
2.449  
2.4485  
2.448  
-40 -20  
0
20  
40  
60  
80 100 120 140 160  
-40 -20  
0
20  
40  
60  
80 100 120 140 160  
Temperature (C)  
Temperature (C)  
6-6. IADJ Internal Clamp Voltage vs Temperature  
6-5. Low-Side Sinking Current Limit vs Temperature  
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6.6 Typical Characteristics (continued)  
40°C < TJ < 150°C, VIN = 14 V, VUDIM = 5 V, VIADJ = 2.1V , CVCC = 2.2 μF, CBST = 1 nF, CCOMP = 1 nF, RCS = 100 mΩ,  
RON = 401 kΩ, VAPWM = 5 V, fSW = 200 kHz  
6
4
2
0
-2  
-4  
-6  
0.25 0.5 0.75  
1
1.25 1.5 1.75  
VIADJ (V)  
2
2.25 2.5 2.75  
6-7. V(CSP--CSN) Sense Threshold vs Temperature  
6-8. V(CSP--CSN) Sense Error vs IADJ Setpoint  
1.65  
1.6  
1.55  
1.5  
1.45  
1.4  
-40 -20  
0
20  
40  
60  
80 100 120 140 160  
Temperature (C)  
6-9. Internal Ramp Generator Frequency vs Temperature  
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7 Detailed Description  
7.1 Overview  
The TPS92643-Q1 is a wide input, synchronous buck LED driver. The device can deliver up to 3 A of continuous  
current and power a single string of one to 10 series-connected LEDs. The device implements an adaptive on-  
time current regulation control technique to achieve fast transient response. This architecture uses a comparator  
and a one-shot on-timer that varies inversely with input and output voltage to maintain a near-constant  
frequency. The integrated low offset rail-to-rail error amplifier enables closed-loop regulation of LED current and  
ensures better than 4% accuracy over a wide input, output, and temperature range. The LED current reference  
is set by the IADJ pin and is programmed by a voltage divider to achieve over a 15:1 linear analog dimming  
range. The high impedance IADJ input simplifies LED current binning and thermal protection.  
The TPS92643-Q1 device incorporates an internal ramp generator to control LED current through pulse width  
modulation (PWM) dimming. The PWM duty cycle can be varied from 0% to 100% by modulating the analog  
voltage on APWM from VRAMP(LOW) to VRAMP(HIGH). The PWM dimming frequency is internally set to typical value  
of 1.5 kHz. In addition, an external PWM input can control current by driving UDIM input. When both UDIM and  
APWM inputs are present, the internal PWM control command is derived by ANDing the two pulse width  
modulated signals. The APWM input can be tied to VCC to enable only external PWM control. Alternatively,  
APWM input can be biased using NTC to scale average LED current and enable temperature foldback protection  
of LEDs. This device optimizes the inductor current response and is capable of achieving over a 1000:1 PWM  
dimming ratio.  
The device incorporates enhanced programmable fault features, including the following:  
Cycle-by-cycle switch overcurrent limit  
Input undervoltage protection  
Boot undervoltage protection  
Comp overvoltage warning  
Thermal warning  
LED short-circuit indication  
In addition, thermal shutdown (TSD) protection is implemented to limit the junction temperature at 175°C  
(typical).  
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7.2 Functional Block Diagram  
5V LDO  
VIN  
VCC  
Regulator  
2.45 V  
1.22 V  
Internal  
References  
Thermal  
Limit  
UVLO  
Standby  
BST  
VIN  
+
BST UVLO  
On-time  
Min on-time  
Min off-time  
RON  
On-Time  
Generator  
VIN  
VCSP  
LEB  
10  
A
Current  
Limit  
HS Limit  
UDIM  
+
PWM(DIM)  
Circuit  
UVLO and  
PWM detection  
VBST(UV)  
SW  
Current  
Limit  
Circuit  
LS Limit  
COMP  
100 mV  
Fault  
VCC  
LEB  
Reset  
Logic  
Logic  
+
CompUV  
CompOV  
PGND  
FLT  
VCOMP(RISE)  
+
VCOMP(OV)  
+
Short  
VCSP(SHORT)  
Valley Current  
CompOV and Short Fault  
VCC  
Control  
CSP  
R
Internal  
Ramp  
Generator  
R
+
CSN  
IADJ  
Error Amplifier  
VRAMP(HIGH)  
Int. PWM  
+
VRAMP(LOW)  
14R  
VIADJ(CLAMP)  
PWM(APWM)  
+
APWM  
AGND  
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7.3 Feature Description  
7.3.1 Internal Regulator  
The TPS92643-Q1 incorporates a 36-V input voltage rated linear regulator to generate the 5-V (typical) VCC bias  
supply and other internal reference voltages. The device monitors the VCC output to implement UVLO protection.  
Operation is enabled when VCC exceeds the VCC(UVLO) rising threshold and is disabled when VCC drops below  
VCC(UVLO) falling threshold. The comparator provides 200 mV of hysteresis to avoid chatter during transitions.  
The VCC UVLO thresholds are internally fixed and cannot be adjusted. An internal current limit circuit is  
implemented to protect the device during VCC pin short-circuit conditions. The VCC supply powers the internal  
circuitry, the low-side gate driver and the bootstrap supply for high-side gate driver. Place a bypass capacitor in  
the range of 4.7 μF to 10 μF close to the device, across the VCC pin to AGND. The capacitor from VCC must  
be five times larger than the bootstrap capacitor, CBST to support proper operation. The regulator operates in  
dropout when input voltage, VIN falls below 5 V, forcing VCC to be lower than VIN by VDO for a 20-mA supply  
current. The VCC is a regulated output of the internal regulator and is not recommended to be driven from an  
external power supply.  
7.3.2 Buck Converter Switching Operation  
The following operating description of the TPS92643-Q1 refers to the Functional Block Diagram and the  
waveforms in 7-1. The main control loop of the TPS92643-Q1 is based on an adaptive on-time pulse width  
modulation (PWM) technique that combines a constant on-time control with an inductor valley current sense  
circuit for pseudo-fixed frequency operation. This proprietary control technique enables closed-loop regulation of  
LED current and fast dynamic response necessary to meet the requirements for dimming animation and fault  
protection.  
V(CSP-CSN)  
IL × RCS  
VVAL  
t
VSW  
VIN  
0
t
tON  
tOFF  
tSW  
7-1. Adaptive On-Time Buck Converter Waveforms  
In steady state, the high-side MOSFET is turned on at the beginning of each cycle. The on-time duration of this  
MOSFET is controlled by an internal one-shot timer and the high-side MOSFET is turned off after the timer  
expires. The one-shot timer duration is set by the output voltage measured at the CSP pin, VCSP, and the input  
voltage measured at the VIN pin, VIN, to maintain a pseudo-fixed frequency. During the on-time interval, the  
inductor current increases with a slope proportional to the voltage applied across its terminals (VIN VCSP).  
The low-side MOSFET is turned on after a fixed dead time and the inductor current then decreases with the  
constant slope proportional to the output voltage, VCSP. Inductor current measured by the external sense resistor  
is compared to the valley threshold, VVAL, by an internal high-speed comparator. This MOSFET is turned off and  
the one-shot timer is initiated when the sensed inductor current falls below the valley threshold voltage. The  
high-side MOSFET is turned on again after a fixed dead time.  
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The internal rail-to-rail error amplifier sets the valley threshold voltage and regulates the average inductor current  
based on a reference value set by VIADJ pin. A simple integral loop compensation circuit consisting of a capacitor  
connected from the COMP pin to GND provides a stable and high-bandwidth response. As the inductor current  
is directly sensed by an external resistor, the device operation is not sensitive to the ESR of the output  
capacitors and is compatible with common multilayered ceramic capacitors (MLCC).  
7.3.3 Bootstrap Supply  
The TPS92643-Q1 contains both high-side and low-side N-channel MOSFETs. The high-side gate driver works  
in conjunction with an internal bootstrap diode and an external bootstrap capacitor, CBST. During the on-time of  
the low-side MOSFET, the SW pin voltage is approximately 0 V and CBST is charged from the VCC supply  
through the internal diode and external RBST resistor. TI recommends a 0.1-µF to 2.2-µF capacitor and 2.2-Ω to  
10-Ωresistor connected in series between the BST and SW pins.  
VCC  
BST  
+
BST UVLO  
VIN  
RBST  
LEB  
CBST  
Current  
Limit  
Circuit  
HS Limit  
+
VBST(UV)  
SW  
7-2. Bootstrap Network  
A larger capacitor is required to prevent a bootstrap undervoltage fault when operating at low PWM dimming  
frequencies. Noise due to stored charge is reduced by the RBST. In addition, the RBST resistor allows  
optimization of EMI with respect to efficiency. A larger RBST resistor results in lower SW node rise time and  
allows energy in SW node harmonics to roll off near 100-MHz frequency. Switching with slower slew rate also  
decreases the efficiency.  
7.3.4 Switching Frequency and Adaptive On-Time Control  
The TPS92643-Q1 uses an adaptive on-time control scheme and does not have a dedicated on-board oscillator.  
The one-shot timer is programmed by the RON resistor. The on-time is calculated internally using 方程式 1 and is  
inversely proportional to the measured input voltage, VIN, and directly proportional to the measured CSP voltage,  
VCSP  
.
V
12  
CSP  
t
= 10 × 10  
× R  
×
(1)  
ON  
ON  
V
IN  
Given the duty ratio of the buck converter is VCSP/VIN, the switching period, TSW, remains nearly constant over  
different operating points. Use 方程2 to calculate the switching period.  
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V
CSP  
12  
T
= t  
×
= 10 × 10  
× R  
ON  
(2)  
SW  
ON  
V
IN  
The switching frequency is calculated internally using 方程3.  
1
12  
f
=
(3)  
SW  
10 × 10  
× R  
ON  
The minimum or maximum duty cycle is limited to finite minimum on-time, TON(MIN) and minimum off-time,  
TOFF(MIN), respectively. As on-time is constant, the frequency is also a dependent on the efficiency of the device,  
ηREG, excluding inductor and sense resistor losses.  
1
f
=
(4)  
SW  
12  
10 × 10  
× R  
ON  
× η  
REG  
TI recommends a switching frequency setting between 100 kHz and 2.2 MHz.  
7.3.5 Minimum On-Time, Off-Time, and Inductor Ripple  
Buck converter operation is impacted by minimum on-time, minimum off-time, and minimum peak-to-peak  
inductor ripple limitations. The converter reaches the minimum on-time of 96 ns (typical) when operating with  
high input voltage and low-output voltage. In this control scheme, the off-time continues to increase and the  
switching frequency reduces to regulate the inductor current and LED current to the desired value.  
V
OUT MIN  
f
=
; t = t  
ON MIN  
(5)  
SW MIN  
ON  
T
× V  
ON MIN  
IN MAX  
The converter reaches the minimum off-time of 91 ns (typical) when operating in dropout (low input voltage and  
high output voltage). As the on-time and off-time are fixed, the duty cycle is constant and the buck converter  
operates in open-loop mode. The inductor current and LED current are not in regulation.  
The behavior and response of valley comparator is dependent on sensed peak-to-peak voltage ripple,  
ΔV(CSP-CSN), and is a function of current sense resistor, RCS, and peak-to-peak inductor current ripple,  
ΔiL(PK-PK). To ensure periodic switching, the sensed peak-to-peak ripple must exceed the minimum value. At  
high (near 100%) or low (near 0%) duty cycles, the inductor current ripple may not be sufficient to ensure  
periodic switching. Under such operating conditions, the converter transitions from periodic switching to a burst  
sequence, forcing multiple on-time and off-time cycles at a rate higher than the programmed frequency. Although  
the converter may not operate in a periodic manner, the closed-loop control continues regulating the average  
LED current with a larger ripple value corresponding to higher peak-to-peak inductor ripple. TI recommends  
choosing an inductor, output capacitor, and switching frequency to ensure minimum sensed peak-to-peak ripple  
voltage under nominal operating condition is greater than 8 mV. The Application and Implementation section  
summarizes the detailed design procedure.  
7.3.6 LED Current Regulation and Error Amplifier  
The reference voltage, VIADJ, set by the VIADJ and is internally scaled by a gain factor of 1/14 through a resistor  
network. An internal rail-to-rail error amplifier generates an error signal proportional to the difference between the  
scaled reference voltage (VIADJ / 14) and the inductor current measured by the differential voltage drop between  
CSP and CSN, V(CSP-CSN). This error drives the COMP pin voltage, VCOMP, and directly controls the valley  
threshold of the inductor current. Zero average DC error and closed-loop regulation is achieved by implementing  
an integral compensation network consisting of a capacitor connected from the output of the error amplifier to  
GND. As a good starting point, TI recommends a capacitor value between 1 nF and 10 nF between the COMP  
pin and GND. The choice of compensation network must ensure a minimum of 60° of phase margin and 10 dB  
of gain margin.  
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CSP1  
CSN1  
Current Sense Amplifier  
500 uS  
Valley Current  
Control  
10k  
10k  
+
COMP1  
2.45 V  
Division by 14  
V-I Converter  
+
VIADJ  
DAC  
IADJ1  
0 V to 2.45 V  
140k  
7-3. Closed-Loop LED Current Regulation  
LED current is dependent on the current sense resistor, RCS. Use 方程15 to calculate the LED current.  
LED current accuracy is a function of the tolerance of the external sense resistor, RCS, and the variation in the  
sense threshold, V(CSP-CSN), caused by internal mismatch and temperature dependency of the analog  
components. The TPS92643-Q1 incorporates low offset rail-to-rail amplifiers, and is capable of achieving LED  
current accuracy of ±4% over common-mode range and a junction temperature range of 40°C to 150°C.  
7.3.7 Start-Up Sequence  
The start-up circuit allows the COMP pin voltage to gradually increase, thus reducing the LED current overshoot  
and current surges. The switching operation is initiated after the COMP pin voltage exceeds 2.45 V. A 440-mV  
hysteresis window allows the device to operate when COMP voltage is within the expected operating range of  
2.2 V to 2.7 V. Switching is disabled on detection of low COMP voltage to avoid excessive negative inductor  
current.  
The duration of soft start, tss, depends on the size of the compensation capacitor and the error amplifier source  
current, ICOMP(SRC)  
.
2.45 × C  
I
COMP  
t
=
(6)  
SS  
COMP SRC  
The source current, ICOMP(SRC) is a function of the transconductance, gM, of the error amplifier and error  
generated between the reference and the current sensed voltage.  
V
IADJ  
14  
I
= g  
×
V  
CSP CSN  
(7)  
COMP SRC  
M
With no current flowing through the LEDs, the soft start duration depends on the choice of compensation  
capacitor, CCOMP, and the reference voltage, VIADJ  
.
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VIADJ  
0.1  
VUDIM  
2.45  
0
VCOMP  
2.45  
440 mV  
t
VSW  
VIN  
0
t
ILED  
t
7-4. Soft-Start Sequence  
The open drain fault indicator, FLT, is set low when the COMP voltage deviates from the nominal range and  
exceeds VCOMP(OV) threshold. This setting indicates a fault condition where the converter is operating in open-  
loop and the LED current is out of regulation. The device can be disabled by setting IADJ input below 100 mV or  
controlling the UDIM input.  
7.3.8 Analog Dimming and Forced Continuous Conduction Mode  
Analog dimming is accomplished by the voltage on IADJ pin, VIADJ. The TPS92643-Q1 improves the linear  
range of analog dimming by supporting forced continuous conduction mode of operation. With synchronous  
MOSFETs, the inductor current is allowed to go negative for part of the switching cycle, thus enabling linear  
dimming with over 15:1 dimming range. TI recommends a 10-nF capacitor from IADJ pin to AGND pin to  
improve noise sensitivity.  
7.3.9 External PWM Dimming and Input Undervoltage Lockout (UVLO)  
The UDIM pin is a multifunction input that features an accurate input voltage detection based on band-gap  
thresholds with programmable hysteresis as shown in 7-5. This pin functions as the external PWM dimming  
input for the LEDs and monitors VIN to detect dropout and undervoltage conditions. When the rising pin voltage  
exceeds the 2.45-V threshold, 10 µA (typical) of current is driven out of the UDIM pin into the resistor divider  
providing programmable hysteresis. TI recommends a bypass capacitor value of 1 nF between the UDIM pin and  
GND to improve noise immunity.  
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100 mV  
+
VIN  
VBG  
PWM and  
Dropout  
PWM  
Standard  
PWM  
Dropout  
Detecon  
V5A  
RUV2  
2VBG  
10  
A
+
DDIM  
RUVH  
10 k  
UDIM  
RUV1  
CUDIM  
Inverted  
QDIM  
PWM  
7-5. External PWM Dimming  
The brightness of LEDs can be varied by modulating the duty cycle of the signal directly connected to the UDIM  
input. In addition, either an n-channel MOSFET or a Schottky diode can be used to couple an external PWM  
signal when using UDIM input in conjunction with UVLO functionality. With an n-channel MOSFET, the  
brightness is proportional to the negative duty cycle of the external PWM signal. With a Schottky diode, the  
brightness is proportional to the positive duty cycle of the external PWM signal.  
Dropout and input undervoltage protection is achieved by connecting the resistor divider network from VIN to  
UDIM pin and UDIM pin to GND. Dropout protection is activated when UDIM pin voltage drops below  
VUDIM(DO, FALL) threshold but is held above VUDIM(EN) threshold. In dropout protection mode, the device disables  
the error amplifier and disconnects the COMP pin to maintain charge on the compensation network. The device  
continues switching, ensuring fast response with minimum led current overshoot as the converter recovers from  
dropout condition. The minimum input voltage, below which drop protection is activated is programmed using 方  
8.  
3
R
+ 10 × 10 × R  
+ R  
UV1 UV2  
UVH  
V
= V  
I  
×
R +  
UV2  
(8)  
IN DO, FALL  
IN DO, RISE  
UDIM DO  
R
UV1  
方程式 9 shows the input voltage rising threshold. When VIN exceeds the rising threshold, the error amplifier is  
enabled, the COMP pin is connected to the compensation network. The control loop now regulates the LED  
current regulation.  
R
+ R  
UV1  
R
UV2  
V
= V  
×
UDIM DO, RISE  
(9)  
IN DO, RISE  
UV1  
Additional hysteresis to internal 100 mV is programmed by connecting an external resistor, RUVH in series with  
UDIM pin. This connection allows the standard resistor divider to have smaller values, minimizing PWM delays.  
Input undervoltage protection is triggered when UDIM pin voltage drops below VUDIM(EN) thresholds. The device  
responds to very low VIN voltage or to the external PWM input signal by disabling the error amplifier,  
disconnecting the COMP pin and tri-stating the switch node. With switch disabled, inductor current and the LED  
current drops to zero and the charge on the compensation network is maintained. On rising edge of PWM or  
when VIN exceeds the internal hysteresis of 100 mV, the converter resumes switching operation. The inductor  
current quickly ramps to the previous steady-state value.  
方程10 defines the VIN UVLO rising threshold.  
R
+ R  
UV1  
R
UV2  
V
= V  
×
UDIM EN,RISE  
(10)  
IN UVLO,RISE  
UV1  
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Use 方程11 to determine the VIN UVLO falling threshold.  
R
+ R  
UV1  
R
UV2  
V
= V  
×
UDIM EN, FALL  
(11)  
IN UVLO, FALL  
UV1  
7.3.10 Analog Pulse Width Modulator Circuit  
The TPS92643-Q1 features analog circuitry to generate an internal PWM dimming signal. The frequency of the  
internal PWM signal is fixed to 1.5 kHz and the duty cycle is proportional to the applied voltage to APWM pin,  
VAPWM, according to 方程12:  
V
1  
APWM  
1.45  
D
=
× 100  
(12)  
PWM INT  
2.45 V  
APWM  
1 V  
DPWM(INT)  
7-6. APWM Waveform  
The internal PWM signal is ANDed with the external PWM signal applied to UDIM pin. Hence, if this pin is  
unused it should be tied to VCC pin. The TPS92643-Q1 stops switching if VAPWM falls below 1.0 V. Pulse width  
modulated thermal fold-back can be implemented by connecting a NTC resistor, in conjunction with a voltage  
divider network, to APWM pin. TI recommends a bypass capacitor of 10 nF between APWM pin and GND to  
improve noise immunity.  
7.3.11 Output Short and Open-Circuit Faults  
The TPS92643-Q1 monitors the CSN voltage to detect output short circuit faults. A short failure is indicated by  
open drain FLT output when the CSN voltage drops below 1.5 V (typical). The device continues to regulate  
current and operate without interruption in case of short circuit. A short-circuit fault does not impact the device  
behavior. The device continues to operate and regulate current without interruption.  
An LED open-circuit fault ultimately causes the output voltage to increase and settle close to the input voltage.  
When this event occurs, the TPS92643-Q1 switching operation is then controlled by the fixed on-time and  
minimum off-time resulting in a duty cycle close to 100%. The COMP pin voltage exceeds the COMP  
overvoltage threshold, VCOMP(OV), and the fault in indicated by FLT output. However, during open circuit, the  
dynamic behavior of the device and buck converter is influenced by the input voltage, VIN, and the output  
capacitor, COUT, value. The device response to open circuit can be categorized into the following two distinct  
cases.  
Case 1: For a Buck converter design with a small output capacitor, the switching operation in open load  
condition exits the tank resonance forcing the output voltage to oscillate. The frequency and amplitude of the  
oscillation are based on the resonant frequency and Q-factor of the second order tank network.  
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VCSN  
VIN  
t
VCOMP  
tOC  
VCOMP(OV)  
t
7-7. Open-Circuit Condition with Output Voltage Oscillation  
Case 2: For a buck converter design with large output capacitor the inductor Q-factor and resonant frequency  
are much lower than the switching frequency. In this case, output voltage rises to input voltage and the converter  
continues to switch with minimum off-time.  
VCSN  
VIN  
t
7-8. Open-Circuit Condition with Minimum Off-Time Operation  
The voltage transient imposed on CSP and CSN inputs during short circuit and open circuit is dependent on the  
output capacitance and is influenced by the cable harness impedance. The inductance associated with a long  
cable harness resonates with the charge stored on the output capacitor and forces CSP and CSN voltage to ring  
above VIN and below ground. The magnitude of the voltage overshoot above VIN and below ground are  
dependent on the parasitic cable harness inductance and resistance.  
CSN  
CSP  
VIN  
LPAR  
tOC(+)  
RCS  
LED+  
SW  
tSH  
COUT  
LED  
LPAR  
tOC(  
)
PGND  
7-9. Cable Harness Parasitic Inductance  
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When using a long cable harness, TI recommends diodes to clamp the voltage across CSP and CSN input, as  
shown in 7-10. TI recommends a low forward voltage Schottky diode or a fast recovery silicon diode with  
reverse blocking voltage rating greater than the maximum output voltage. The diode is required to be placed  
close to the output capacitor.  
VIN  
DFP  
LED+  
SW  
COUT  
DRP  
PGND  
LED  
7-10. Transient Protection Using an External Diode  
7.3.12 Overcurrent Protection  
The device is protected from overcurrent conditions with cycle-by-cycle current limiting on both the high-side and  
the low-side MOSFETs.  
The device turns off the high-side MOSFET and discharges the COMP capacitor when the drain current exceeds  
4.8-A typical. The low-side switch is turned on to discharge the inductor current and output capacitor.  
When the low-side switch is turned on, the switch current is also sensed and monitored. The device turns off  
both high-side and low-side MOSFETs and discharges the COMP capacitor when the drain current (from drain to  
PGND) exceeds 3.2-A typical.  
IL  
4.8  
ILIM(HS)  
iL  
tON  
tOFF  
0.0  
(t)  
-3.2  
ISINK(LS)  
7-11. Overcurrent Protection Thresholds  
The device employs hiccup mode overcurrent protection. In hiccup mode, the device shuts itself down and  
attempts to start after TOC. Hiccup mode helps reduce the device power dissipation under severe overcurrent  
conditions.  
7.3.13 Thermal Shutdown  
Thermal shutdown prevents the device from extreme junction temperatures by turning off the internal switches  
when the IC junction temperature exceeds 175(typical). Thermal shutdown does not trigger below 158.  
After thermal shutdown occurs, hysteresis prevents the device from switching until the junction temperature  
drops to approximately 160. When the junction temperature falls below 160(typical), the device attempts to  
start up.  
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7.3.14 Fault Indicator and Diagnostics Summary  
7-1 summarizes the device behavior under fault conditions.  
7-1. Fault Description  
FAULT  
DETECTION  
DESCRIPTION  
The thermal protection is activated in the event the maximum MOSFET temperature  
exceeds the typical value of 175°C. This feature is designed to prevent overheating  
and damage to the internal switching MOSFETs.  
Thermal protection  
TJ > 175°C  
VCC(RISE) < 4.4 V  
VCC(FALL) < 4.2 V  
VCC undervoltage  
lockout  
The device enters the Undervoltage Lockout (UVLO). The switching operation is  
disabled, the COMP capacitor is discharged.  
The device disables error amplifier and disconnects the compensation network for the  
corresponding channel. Error amplifier is enabled and compensation network is  
internally connected when the input voltage rises above the dropout rising threshold,  
VIN dropout  
protection  
VUDIM < 2.34 V  
VIN(DO,RISE)  
The device disables switching operation for the corresponding channel. Switching is  
enabled when the input voltage rises above the turn-on threshold, VIN(UVLO,RISE)  
.
VIN undervoltage  
lockout  
VUDIM < 1.12 V  
.
VBST(RISE) < 3.2 V  
VBST(FALL) < 2.93 V  
The device turns off the high-side MOSFET and turns on the low-side MOSFET for the  
corresponding channel. Normal switching operation is resumed after the bootstrap  
voltage exceeds 3.2 V.  
BST undervoltage  
lockout  
The FLT flag is set low to indicate that the COMP voltage exceeded the normal  
operating range. This condition indicates output open-circuit fault.  
COMP overvoltage  
Short output  
VCOMP > 3.2 V  
VCSN < 1.5 V  
IHS > 4.8 A  
The FLT flag is set low to indicate an output short-circuit condition based on sensed  
CSN voltage.  
High-side switch  
current limit  
The device turns off the high-side MOSFET, turns on low-side MOSFET and  
discharges the COMP capacitor. The device attempts to restart after a delay of 5.5 ms.  
Low-side switch  
current limit  
The device turns off both high-side and low-side MOSFETs and discharges the COMP  
capacitor. The device attempts to restart after a delay of 5.5 ms.  
ILS > 3.2 A  
Output open and short circuit faults force the FLT pin low when biased through an external resistor and  
connected to a 5-V supply. The FLT output can be used in conjunction with a microcontroller or system basis  
chip (SBC) as an interrupt and aid in fault diagnostics.  
7.4 Device Functional Modes  
This device has no additional functional modes.  
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8 Application and Implementation  
备注  
Information in the following applications sections is not part of the TI component specification, and TI  
does not warrant its accuracy or completeness. TIs customers are responsible for determining  
suitability of components for their purposes, as well as validating and testing their design  
implementation to confirm system functionality.  
8.1 Application Information  
8-1 shows a schematic of a typical application for the TPS92643-Q1.  
RCS  
L
LED+  
D1  
COUT  
1
2
16  
SW  
SW  
PGND  
GND  
D2  
CIN1  
15  
14  
RBST  
CBST  
VIN  
VIN  
3
4
BST  
VCC  
VIN  
RON  
RUV2  
RUV1  
CIADJ  
13  
12  
11  
10  
9
5
RON  
UDIM  
CSP  
CSN  
FLT  
IADJ  
RPWM1  
RIADJ2  
CCOMP  
6
7
COMP  
AGND  
PWM  
CVCC  
CUDIM  
RIADJ1  
RNTC  
CAPWM  
8
APWM  
8-1. Typical Application Schematic  
The TPS92643-Q1 controller is suitable for implementation of step-down LED driver topology. Use the following  
design procedure to select component values for the TPS92643-Q1 device. This section presents a simplified  
discussion of the design process for the Buck converter.  
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8.1.1 Duty Cycle Considerations  
The switch duty cycle, D, defines the converter operation and is a function of the input and output voltages. In  
steady state, the duty cycle is defined using 方程13:  
V
CSN  
D =  
(13)  
V
IN  
The buck converter maximum operating duty cycle, DMAX, at minimum input voltage, VIN,MIN and maximum LED  
voltage, VCSN,MAX  
.
V
CSN, MAX  
D
=
(14)  
MAX  
V
IN, MIN  
There is no limitation for small duty cycles, because at low duty cycles, the switching frequency is reduced as  
needed to always ensure current regulation. The maximum duty cycle attainable is limited by the minimum off-  
time duration and is a function of switching frequency.  
8.1.2 Switching Frequency Selection  
Nominal switching frequency is set by programming the RON resistor. The switching varies slightly over operating  
range and temperature based on converter efficiency. 8-1 shows common switching frequencies and  
corresponding RON resistor values.  
8-1. Center Switching Frequency Setting  
SWITCHING FREQUENCY (kHz)  
RON (kΩ)  
267  
243  
221  
50  
400  
435  
480  
2000  
2200  
44.2  
8.1.3 LED Current Programming  
The LED current is set by the external current sense resistor, RCS, and the analog adjust voltage, VIADJ. The  
LED current can be programmed by varying VIADJ between 140 mV to 2.3 V. The LED current can be calculated  
using 方程15:  
V
IADJ  
I
=
(15)  
LED  
14 × R  
CS  
The LED current can be programmed by varying VIADJ between 140 mV and 2.3 V. TI recommends a 10-nF  
capacitor from IADJ pin to AGND pin to filter high frequency switching noise.  
8.1.4 Inductor Selection  
The inductor is sized to meet the ripple specification at maximum operating duty cycle. TI recommends a  
minimum sensed peak-to-peak voltage ripple (ΔV(CSP-CSN)) of 8 mV to ensure periodic switching operation  
under.  
V  
= i × R  
CS  
(16)  
CSP CSN  
L
Use 方程17 to calculate the inductor value.  
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V
V  
V
CSN, MAX  
IN, MIN  
CSN, MAX  
SW  
L =  
×
(17)  
V
i × f  
IN, MIN  
L
The maximum inductor current ripple occurs at 50% duty cycle. Use 方程式 18 to calculate the maximum peak-  
to-peak inductor current ripple, ΔiL(MAX)  
.
V
IN TYP  
i  
=
(18)  
L MAX  
4 × L × f  
SW  
Use 方程式 19 and 方程式 20 to calculate the RMS and peak currents through the inductor. Make sure that the  
inductor is rated to handle these currents.  
2
ΔI  
L MAX  
12  
2
i
=
I
+
(19)  
(20)  
L RMS  
L PK  
LED MAX  
Δi  
L MAX  
2
i
= I  
+
LED MAX  
8.1.5 Output Capacitor Selection  
The output capacitor value depends on the total series resistance of the LED string, rD, and the switching  
frequency, fSW. The capacitance required for the target LED ripple current, ΔiLED, is calculated using 方程21.  
Δi  
L MAX  
× r × Δi  
D LED  
C
=
(21)  
OUT  
8 × f  
SW  
When choosing the output capacitors, consider the ESR and ESL characteristics because they directly impact  
the LED current ripple. Ceramic capacitors are the best choice due to the following:  
Low ESR  
High ripple current rating  
Long lifetime  
Good temperature performance  
With ceramic capacitor technology, consider the derating factors associated with higher temperature and DC  
bias operating conditions. TI recommends an X7R dielectric with a voltage rating greater than maximum LED  
stack voltage.  
8.1.6 Input Capacitor Selection  
The input capacitor buffers the input voltage for transient events and decouples the converter from the supply. TI  
recommends a 10-µF input capacitor across the VIN pin and PGND placed close to the device, and connected  
using wide traces. X7R-rated ceramic capacitors are the best choice due to the low ESR, high ripple current  
rating, and good temperature performance.  
In addition, a small case size 100-nF ceramic capacitor must be used across VIN to PGND, immediately  
adjacent to the device. This usage provides a high-frequency bypass for the control circuits internal to the  
device. These capacitors also suppress SW node ringing, which reduces the maximum voltage present on the  
SW node and EMI.  
The capacitance can be increased to further limit the input voltage deviation during PWM dimming operation.  
8.1.7 Bootstrap Capacitor Selection  
The bootstrap capacitor biases the high-side gate driver during the high-side FET on-time. The required  
capacitance depends on the PWM dimming frequency, PWMFREQ, and is sized to avoid boot undervoltage and  
fault during PWM dimming operation. The bootstrap capacitance, CBST, is calculated using 方程22:  
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I
Q BST,MAX  
C
=
(22)  
BST  
V
+ V  
V  
× PWM  
FREQ  
CC  
BST HYS  
BST UV  
8-2 summarizes the TI recommended bootstrap capacitor value for different PWM dimming frequencies.  
8-2. Bootstrap Capacitor Value  
PWM DIMMING FREQUENCY (Hz)  
BOOTSTRAP CAPACITOR (µF)  
1500  
1300  
1000  
800  
0.1  
0.15  
0.22  
0.22  
0.33  
0.47  
1
600  
400  
200  
100  
2.2  
8.1.8 Bootstrap Resistor Selection  
A resistor can be connected between the CBST capacitor and BST pin. A 4.7 resistor between the pins eliminates  
overshoot. Even with 2.2 , overshoot and ringing are minimal, less than 4 V if input capacitors are placed  
correctly. A resistor value above 10 is undesirable because the resulting incremental improvement in EMI is  
not enough to justify further decreased efficiency.  
8.1.9 Compensation Capacitor Selection  
TI recommends a simple integral compensator to achieve stable operation across the wide operating range. The  
buck converter behaves as a single pole system with additional phase lag caused by the switching behavior. The  
gain and phase margin are, consequently determined by the choice of the switching frequency and are  
independent of other design parameters. TI recommends a 1-nF to 10-nF capacitor to achieve bandwidth  
between 4 kHz and 40 kHz. The choice of compensation capacitor impacts the transient response and PWM  
dimming performance. TI recommends a larger compensation capacitor (lower bandwidth) to limit the LED  
current overshoot on the rising edge of internal or external PWM signal.  
8-3. Compensation Capacitor Value  
BANDWIDTH (kHz)  
BOOTSTRAP CAPACITOR (nF)  
40  
18  
12  
8.5  
5.8  
4.8  
4
1
2.2  
3.3  
4.7  
6.8  
8.2  
10  
8.1.10 Input Dropout and Undervoltage Protection  
8-1 shows that the undervoltage protection threshold is programmed using a resistor divider, RUV1 and RUV2  
,
from the input voltage, VIN to PGND. Use 方程23 and 方程24 to calculate the resistor values.  
2 × V  
I
V
IN DO, FALL  
IN UVLO, RISE  
UDIM DO  
3
R
R
=
=
10 × 10  
(23)  
(24)  
UV2  
I
UDIM DO  
V
UDIM EN, RISE  
× R  
UV1  
UV2  
V
V  
IN UVLO, RISE  
UDIM EN, RISE  
A capacitor of 1 nF from UDIM pin to GND is placed close to device to improve noise immunity.  
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8.1.11 APWM Input and Thermal Protection  
8-1 shows APWM input can be used in conjunction with NTC resistor to implement thermal foldback  
protection. TI recommends a network of 10-kresistor and a 100-kNTC with β-value (25/50°C) of 4250 K to  
implement thermal fold back from 80°C to 125°C.  
8.1.12 Protection Diodes  
External Schottky diodes are required to protect the CSP / CSN node by clamping the voltage during short circuit  
and open-circuit transients. The Schottky diode must be selected based on the length of the cable harness and  
the choice of output capacitor. TI recommends a Schottky diode with low forward voltage drop at room-  
temperature and non-repetitive peak surge current rating of 10 A for duration of 5 µs. The diodes from CSN to  
VIN and GND to CSN must be located close to the pin.  
8.2 Typical Application  
L2  
R14  
15uH  
LED+  
0.065  
C15  
50V  
4.7uF  
D4  
CSP  
U2  
CSN  
D5  
GND  
VIN  
C16  
100nF  
50V  
C17  
10µF  
50V  
1
2
3
4
5
6
7
8
16  
15  
14  
13  
12  
11  
10  
9
SW  
PGND  
GND  
SW  
VIN  
VIN  
C18 16V  
R15  
R16  
267k  
VCC  
R17  
100k  
BST  
4.7  
1µF  
C19 16V  
VCC  
RON  
PWM  
IADJ  
COMP  
AGND  
APWM  
UDIM  
CSP  
R18  
57.6k  
C20 16V  
D6  
R19  
10k  
10nF  
CSP  
CSN  
R20  
37.4k  
4700pF  
CSN  
C22  
1000pF  
16V  
C21 16V  
10nF  
C23  
10µF  
FLT  
16V  
R21  
48.4k  
17  
R22  
PowerPAD  
GND  
GND  
100k  
TPS92643QPWPRQ1  
VCC  
IADJ  
GND  
R23  
GND  
100k  
nFLT  
APWM  
GND  
8-2. Application Schematic  
8.2.1 Design Requirements  
8-4. Design Parameters  
PARAMETER  
CONDITIONS  
MIN  
TYP  
13.5  
2
MAX  
UNIT  
VIN  
Input voltage  
8
36  
V
NS  
Number of LEDs  
VFLED  
rD  
VCSN  
ILED  
LED forward voltage drop  
LED string series resistance  
Output voltage  
2.6  
200  
5.2  
3
3.4  
500  
6.8  
V
mΩ  
V
N × rD(LED)  
Ns × VFLED  
6
LED current continuous  
100  
2500  
mA  
mA  
LED current ripple  
80  
ΔiLED  
ΔiL  
Defined as percentage peak-to-peak at  
maximum LED current  
Inductor current ripple  
6.2  
%
VIN(DO,RISE)  
VIN(DO,FALL)  
Start input voltage  
Stop input voltage  
Input voltage rising  
Input voltage falling  
9
V
V
7.9  
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8-4. Design Parameters (continued)  
PARAMETER  
CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
Hz  
fPWM  
DPWM  
fSW  
PWM frequency  
200  
PWM dimming duty cycle  
Switching frequency  
Ambient temperature  
4
100  
%
400  
25  
kHz  
°C  
TA  
8.2.2 Detailed Design Procedure  
8.2.2.1 Calculating Duty Cycle  
Solve for duty cycle D, DMAX, and DMIN  
:
V
CSN MAX  
6.8  
8
D
=
=
= 0.85  
(25)  
MAX  
V
IN MIN  
V
CSN MIN  
5.2  
D
=
=
= 0.144  
36  
(26)  
MIN  
V
IN MAX  
8.2.2.2 Calculating Minimum On-Time and Off-Time  
Solve for minimum on-time, tON(DMIN) at minimum duty cycle and minimum off-time, tOFF(DMAX) at maximum duty  
cycle:  
V
CSN MAX  
1
6.8  
8
1
t
t
=
=
×
=
×
= 2125 ns  
= 360 ns  
3
(27)  
(28)  
ON DMAX  
ON DMIN  
V
3
f
IN MIN  
sw  
400 × 10  
V
CSN MIN  
1
5.2  
1
×
=
×
36  
V
f
IN MAX  
sw  
400 × 10  
8.2.2.3 Minimum Switching Frequency  
Confirm minimum switching frequency at tON(DMIN), fSW(MIN)  
:
V
CSN MIN  
5.2  
9  
f
(29)  
sw MIN =  
=
= 401.2 kHz  
t
ON DMIN × V  
360 × 10  
× 36  
IN MAX  
For the design specification, tON(DMIN) > tON(MIN) and fSW(MIN) = fSW  
.
8.2.2.4 LED Current Set Point  
Solve for sense resistor, RCS  
:
V
IADJ MAX  
2.3  
14 × 2.5  
R
=
=
= 0.0657  
(30)  
CS  
14 × I  
LED MAX  
A standard resistor of 65 mΩ with tolerance better than 1 % and low temperature coefficient is selected. The  
power dissipated in RCS is calculated:  
2
2
P
= R × I  
= 0.065 × 2.5 = 0.406 W  
(31)  
sense  
CS  
LED MAX  
A resistor with rated power of 500 mW and above must be selected.  
A resistor divider network, with standard values 57.6 kand 48.4 k, from VCC pin to GND sets the maximum  
LED current reference voltage of 2.3 V. A 10-nF capacitor from IADJ pin to AGND pin is included to filter high  
frequency switching noise.  
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8.2.2.5 Inductor Selection  
The inductor is selected to meet the recommended peak-to-peak voltage ripple, ΔV(CSP-CSN)  
:
V
V  
V
CSN, MAX  
IN, MIN  
CSN, MAX  
SW  
8 6.8  
3  
6.8  
8
6  
L =  
×
=
×
3
= 16.45 × 10  
(32)  
V
i × f  
IN, MIN  
L
155 × 10  
× 400 × 10  
The closest standard capacitor is 15 µH.  
Lower inductor values increase the peak-to-peak inductor current, which minimizes size and cost at the  
expense of reduced efficiency and larger output capacitor.  
Higher inductance values decrease the peak-to-peak inductor current, which increases efficiency but reduces  
the operating range based on minimum sense voltage ripple, ΔV(CSP-CSN) specification.  
8.2.2.6 Output Capacitor Selection  
The minimum output capacitance is selected to meet the LED current ripple specification:  
i  
L MAX  
× i  
D MAX LED  
0.5625  
6  
C
=
=
= 4.4 × 10  
(33)  
OUT  
3
3  
8 × f  
× r  
SW  
8 × 400 × 10 × 0.5 × 80 × 10  
A standard 4.7-µF, 50-V X7R capacitor is selected.  
8.2.2.7 Bootstrap Capacitor Selection  
Referring to 8-2 , a standard 1-µF, 16-V X7R capacitor is selected to support PWM frequency of 200 Hz.  
8.2.2.8 Bootstrap Resistor Selection  
A standard 4.7-bootstrap resistor is selected to limit ringing and mitigate EMI.  
8.2.2.9 Compensation Capacitor Selection  
A compensation capacitor of 4.7 nF is selected to achieve balanced transient response between PWM dimming  
and shunt FET dimming.  
8.2.2.10 VIN Dropout Protection and PWM Dimming  
The resistor divider, RUV1 and RUV2, is set to meet VIN(UVLO,RISE) and VIN(DO,FALL) thresholds.  
2 × 4.5  
7.9  
3
3
R
=
10 × 10 = 100 × 10  
(34)  
(35)  
UV2  
UV1  
6  
6  
10 × 10  
10 × 10  
1.22  
4.5 1.22  
3
3
R
=
× 100 × 10 = 37.2 × 10  
A standard value resistors of 100 kand 37.4 kare selected for RUV2 and RUV1, respectively.  
The external PWM signal is achieved by controlling UDIM input. The device modulates the LED current based  
on the PWM duty cycle of the external signal, coupled through external diode.  
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8.2.3 Application Curves  
Ch1: SW voltage (4 V/div); Ch2: Output voltage (1 V/div); Ch3:  
Inductor current (500 mA/div); Ch4: VIN voltage (4 V/div);  
Time: 2 ms/div  
Ch1: SW voltage (4 V/div); Ch2: Output voltage (1 V/div); Ch3:  
LED current (500 mA/div); Time: 4 µs/div  
8-4. Normal Operation  
8-3. Start-up Transient  
Ch1: SW voltage (4 V/div); Ch2: Output voltage (1 V/div); Ch3:  
Inductor current (500 mA/div); Time: 5 µs/div  
Ch1: SW voltage (4 V/div); Ch2: Output voltage (1 V/div); Ch3:  
Inductor current (500 mA/div); Time: 4 µs/div  
8-6. PWM Dimming (Rising Edge)  
8-5. Normal Operation  
Ch1: SW voltage (4 V/div); Ch2: Output voltage (1 V/div); Ch3:  
Inductor current (500 mA/div); Time: 5 µs/div  
Ch1: SW voltage (4 V/div); Ch2: Output voltage (1 V/div); Ch3:  
LED current (500 mA/div); Ch4: VIN voltage (4 V/div); Time:  
50 ms/div  
8-7. PWM Dimming (Falling Edge)  
8-8. Input Dropout Transient  
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Ch2: Output voltage (1 V/div); Ch3:  
LED current (500 mA/div); Ch4: FLT  
voltage (1 V/div); Time: 20 ms/div  
Ch2: Output voltage (1 V/div); Ch3: LED current (500 mA/div);  
Ch4: FLT voltage (1 V/div); Time: 20 ms/div  
8-9. Output Short-Circuit Fault  
8-10. Output Open-Circuit Fault  
9 Power Supply Recommendations  
The characteristics of the input supply must be compatible with Absolute Maximum Ratings and Recommended  
Operating Conditions in this data sheet. In addition, the input supply must be capable of delivering the required  
input current to the loaded converter.  
If the converter is connected to the input supply through long wires or PCB traces, special care is required to  
achieve good performance. The parasitic inductance and resistance of the input cables can have an adverse  
effect on the operation of the converter. The parasitic inductance, in combination with the low-ESR, ceramic  
input capacitors, can form an under-damped resonant circuit, resulting in overvoltage transients at the input to  
the converter or tripping UVLO. Additional bulk capacitance or an input filter can be required in addition to the  
ceramic bypass capacitors to address converter stability, noise, and EMI concerns.  
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10 Layout  
10.1 Layout Guidelines  
The performance of any switching converter depends as much on the layout of the PCB as the component  
selection. The following guidelines can help design a PCB with the best power converter performance.  
Place ceramic high-frequency bypass capacitors as close as possible to the TPS92643-Q1 VIN and PGND  
pins. Grounding for both the input and output capacitors must consist of localized top side planes that  
connect to the PGND pin.  
Place bypass capacitors for VCC close to the pins and ground the capacitors to device ground.  
Use wide traces for the CBST capacitor and RBST resistor. Place RBST and CBST network as close as possible  
to BST pin and SW pin.  
Differentially route the CSP and CSN pins to sense resistor. Route the traces away from noisy nodes,  
preferably through a layer on the other side of a shielding/ground layer.  
Use ground plane in one of the middle layers for noise shielding.  
Make VIN and ground connection as wide as possible. This action reduces any voltage drops on the input of  
the converter and maximizes efficiency.  
Keep switch area small. Keep the copper area connecting the SW pin to the inductor as short and wide as  
possible. At the same time, the total area of this node must be minimized to help reduce radiated EMI.  
10.1.1 Compact Layout for EMI Reduction  
Radiated EMI is generated by the high di/dt from pulsing currents in switching converters. The larger the area  
covered by the path of a pulsing current, the more electromagnetic emission is generated. The key to minimize  
radiated EMI is to identify the pulsing current path and minimize the area of the path. In buck converters, the  
pulsing current path is from the VIN side of the input capacitors through the HS switch, through the LS switch,  
and then returns to the ground of the input capacitor.  
High-frequency ceramic bypass capacitors at the input side provide primary path for the high di/dt components of  
the pulsing current. Placing ceramic capacitors as close as possible to the VIN and PGND pins is the key to EMI  
reduction.  
The PCB copper connection of the SW pin to the inductor must be as short as possible and just wide enough to  
carry the LED current without excessive heating. Short, thick traces or, copper pours (shapes), must be used for  
high current conduction path to minimize parasitic resistance. Place the output capacitor close to the CSN pin  
and grounded closely to the PGND pin.  
10.1.1.1 Ground Plane  
TI recommends using one of the middle layers as a solid ground plane. The ground plane provides shielding for  
sensitive circuits and traces. the ground plane also provides a quiet reference potential for the control circuitry.  
Connect the GND, AGND and PGND pins to the ground plane using via right next to the bypass capacitors.  
PGND pins are connected to the source of the internal LS switch. They must be connected directly to the  
grounds of the input and output capacitors. The PGND net contains noise at the switching frequency and can  
bounce due to load variations.  
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10.2 Layout Example  
SW  
PGND  
VIN  
1
2
3
4
5
6
7
8
32  
31  
30  
29  
28  
27  
26  
25  
SW  
BST  
VIN  
VCC  
IADJ  
COMP  
AGND  
APWM  
RON  
UDIM  
CSP  
CSN  
FLT  
GND  
10-1. TPS92643-Q1 Layout Example  
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11 Device and Documentation Support  
11.1 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。  
11.2 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》。  
11.3 Trademarks  
TI E2Eis a trademark of Texas Instruments.  
所有商标均为其各自所有者的财产。  
11.4 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.  
11.5 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。  
12 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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PACKAGE OPTION ADDENDUM  
www.ti.com  
12-Jun-2022  
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  
(1)  
(2)  
(3)  
(4/5)  
(6)  
TPS92643QPWPRQ1  
ACTIVE  
HTSSOP  
PWP  
16  
2000 RoHS & Green  
NIPDAU  
Level-3-260C-168 HR  
-40 to 125  
92643Q  
Samples  
(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.  
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 1  
PACKAGE OUTLINE  
PWP0016G  
PowerPAD TM TSSOP - 1.2 mm max height  
S
C
A
L
E
2
.
4
0
0
PLASTIC SMALL OUTLINE  
C
6.6  
6.2  
TYP  
SEATING PLANE  
PIN 1 ID  
AREA  
A
0.1 C  
14X 0.65  
16  
1
2X  
5.1  
4.9  
4.55  
NOTE 3  
8
9
0.30  
0.19  
4.5  
4.3  
NOTE 4  
16X  
B
1.2 MAX  
0.1  
C A  
B
0.18  
0.12  
TYP  
SEE DETAIL A  
2X 0.24 MAX  
NOTE 6  
2X 0.56 MAX  
NOTE 6  
THERMAL  
PAD  
0.25  
GAGE PLANE  
3.29  
2.71  
0.15  
0.05  
0 - 8  
0.75  
0.50  
DETAIL A  
TYPICAL  
(1)  
2.41  
1.77  
4218975/B 01/2016  
PowerPAD is a trademark of Texas Instruments.  
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. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed 0.15 mm per side.  
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.  
5. Reference JEDEC registration MO-153.  
6. Features may not present.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
PWP0016G  
PowerPAD TM TSSOP - 1.2 mm max height  
PLASTIC SMALL OUTLINE  
(3.4)  
NOTE 10  
(2.41)  
SOLDER MASK  
OPENING  
SOLDER MASK  
DEFINED PAD  
SEE DETAILS  
16X (1.5)  
SYMM  
1
16  
16X (0.45)  
(0.95)  
TYP  
(5)  
SYMM  
(3.29)  
SOLDER MASK  
OPENING  
14X (0.65)  
9
8
(0.95) TYP  
METAL COVERED  
BY SOLDER MASK  
(
0.2) TYP  
VIA  
(5.8)  
LAND PATTERN EXAMPLE  
SCALE:10X  
METAL UNDER  
SOLDER MASK  
SOLDER MASK  
OPENING  
SOLDER MASK  
OPENING  
METAL  
0.05 MIN  
ALL AROUND  
0.05 MAX  
ALL AROUND  
SOLDER MASK  
DEFINED  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
PADS 1-16  
4218975/B 01/2016  
NOTES: (continued)  
7. Publication IPC-7351 may have alternate designs.  
8. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
9. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature  
numbers SLMA002 (www.ti.com/lit/slma002) and SLMA004 (www.ti.com/lit/slma004).  
10. Size of metal pad may vary due to creepage requirement.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
PWP0016G  
PowerPAD TM TSSOP - 1.2 mm max height  
PLASTIC SMALL OUTLINE  
(2.41)  
BASED ON  
0.127 THICK  
STENCIL  
16X (1.5)  
1
16  
16X (0.45)  
(3.29)  
SYMM  
BASED ON  
0.127 THICK  
STENCIL  
14X (0.65)  
(R0.05)  
9
8
SYMM  
(5.8)  
SEE TABLE FOR  
METAL COVERED  
BY SOLDER MASK  
DIFFERENT OPENINGS  
FOR OTHER STENCIL  
THICKNESSES  
SOLDER PASTE EXAMPLE  
EXPOSED PAD  
100% PRINTED SOLDER COVERAGE BY AREA  
SCALE:10X  
STENCIL  
THICKNESS  
SOLDER STENCIL  
OPENING  
0.1  
2.69 X 3.68  
2.41 X 3.29 (SHOWN)  
2.20 X 3.00  
0.127  
0.152  
0.178  
2.04 X 2.78  
4218975/B 01/2016  
NOTES: (continued)  
11. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
12. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
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,  
不保证没有瑕疵且不做出任何明示或暗示的担保,包括但不限于对适销性、某特定用途方面的适用性或不侵犯任何第三方知识产权的暗示担  
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  
证并测试您的应用,(3) 确保您的应用满足相应标准以及任何其他功能安全、信息安全、监管或其他要求。  
这些资源如有变更,恕不另行通知。TI 授权您仅可将这些资源用于研发本资源所述的 TI 产品的应用。严禁对这些资源进行其他复制或展示。  
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  
本、损失和债务,TI 对此概不负责。  
TI 提供的产品受 TI 的销售条款ti.com 上其他适用条款/TI 产品随附的其他适用条款的约束。TI 提供这些资源并不会扩展或以其他方式更改  
TI 针对 TI 产品发布的适用的担保或担保免责声明。  
TI 反对并拒绝您可能提出的任何其他或不同的条款。IMPORTANT NOTICE  
邮寄地址:Texas Instruments, Post Office Box 655303, Dallas, Texas 75265  
Copyright © 2022,德州仪器 (TI) 公司  

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