TPS54388CQRTERQ1 [TI]

汽车 2.95V 至 6V、3A、2MHz 同步降压转换器 | RTE | 16 | -40 to 125;
TPS54388CQRTERQ1
型号: TPS54388CQRTERQ1
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

汽车 2.95V 至 6V、3A、2MHz 同步降压转换器 | RTE | 16 | -40 to 125

开关 转换器
文件: 总40页 (文件大小:3413K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
TPS54388C-Q1 汽车2.95V 6V3A2MHz 同步降压转换器  
TPS54388C-Q1 器件集成了 MOSFET通过实施电流  
模式控制来减少外部组件数量通过启用高达 2MHz  
的开关频率来减小电感器尺寸并借助小型 3mm x  
3mm 热增强型 QFN 封装更大限度减小 IC 尺寸从而  
实现小型设计。  
1 特性  
• 符合面向汽车应用AEC-Q100 标准:  
– 温度等140°C +125°CTA  
功能安全型  
有助于进行功能安全系统设计的文档  
• 两个可3A 负载下获得高效率12mΩ(典型  
MOSFET  
TPS54388C-Q1 器件可在工作温度范围内±1% 的精  
确电压基(Vref) 为多种负载提供精确调节。  
集成式 12mMOSFET 515μA典型值的电源  
电流可最大限度提升效率。使用使能引脚进入关断模  
可将关断电源电流降低5.5µA典型值。  
200kHz 2MHz 开关频率  
• 在工作温度范围40°C +150°C内具0.8V  
± 1% 电压基准  
• 与外部时钟同步  
内部欠压锁定设置2.45V但通过使能引脚上的电阻  
器网络对阈值编程可提高该设置值。缓启动引脚可设  
置输出电压启动斜升。一个开漏电源正常信号表示输出  
处于其标称电压值93% 107% 之内。  
• 可调缓启动和排序  
• 欠(UV) 和过(OV) 电源正常输出  
• –40°C +150°C 的工作结温范围  
• 热增强3mm × 3mm 16 WQFN 封装  
TPS54418 引脚兼容  
频率折返和热关断功能负责在过流情况下保护器件。  
器件信息(1)  
• 推出更新版本产品TPS62813-Q1 采用具有可湿  
性侧面2mm x 3mm QFN 封装6V 降压转换器  
封装尺寸标称值)  
器件型号  
封装  
TPS54388C-Q1  
WQFN (16)  
3.00mm × 3.00mm  
2 应用  
(1) 有关所有的可用封装请参阅数据表末尾的可订购产品附录。  
• 低电压、高密度电源系统  
• 针对高性DSPFPGAASIC 和微处理器的负  
载点调节  
宽带网络及光纤通信基础设施  
3 说明  
TPS54388C-Q1 器件是一款具有两个集成 MOSFET  
的全功6V3A、同步降压电流模式转换器。  
100  
C(BOOT)  
V(VIN) = 3 V  
TPS54388C-Q1  
95  
V(VIN)  
C(I)  
VIN  
BOOT  
V(VIN) = 5 V  
90  
R4  
R5  
L(O)  
EN  
PH  
85  
VO  
C(O)  
80  
75  
R1  
R2  
PWRGD  
VSENSE  
70  
65  
60  
SS/TR  
RT/CLK  
COMP  
C(SS)  
Rt  
GND  
AGND  
f
= 500 kHz  
R3  
C1  
(SW)  
Thermal Pad  
55  
50  
VO = 1.8 V  
0
1
2
3
4
5
6
Output Current (A)  
简化原理图  
效率曲线  
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: SLVSDQ8  
 
 
 
 
 
 
TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
Table of Contents  
8 Application and Implementation..................................22  
8.1 Application Information............................................. 22  
8.2 Typical Application.................................................... 22  
9 Power Supply Recommendations................................32  
10 Layout...........................................................................33  
10.1 Layout Guidelines................................................... 33  
10.2 Layout Example...................................................... 34  
11 Device and Documentation Support..........................35  
11.1 Documentation Support.......................................... 35  
11.2 接收文档更新通知................................................... 35  
11.3 支持资源..................................................................35  
11.4 Trademarks............................................................. 35  
11.5 静电放电警告...........................................................35  
11.6 术语表..................................................................... 35  
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................................................7  
7 Detailed Description......................................................11  
7.1 Overview................................................................... 11  
7.2 Functional Block Diagram.........................................12  
7.3 Feature Description...................................................12  
7.4 Device Functional Modes..........................................13  
Information.................................................................... 35  
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 (December 2019) to Revision B (June 2021)  
Page  
• 向“特性”添加了功能安全要点和新推出的类似产品.........................................................................................1  
• 更新了整个文档中的表格、图和交叉参考的编号格式。..................................................................................... 1  
Changes from Revision * (October 2016) to Revision A (December 2019)  
Page  
• 首次公开发布......................................................................................................................................................1  
Copyright © 2023 Texas Instruments Incorporated  
English Data Sheet: SLVSDQ8  
2
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Product Folder Links: TPS54388C-Q1  
 
TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
5 Pin Configuration and Functions  
VIN  
VIN  
1
2
3
4
12 PH  
11 PH  
10 PH  
Thermal  
Pad  
GND  
GND  
9
SS/TR  
5-1. RTE Package 16-Pin WQFN With Exposed Thermal Pad Top View  
5-1. Pin Functions  
PIN  
I/O(1)  
DESCRIPTION  
NAME  
NO.  
AGND  
5
Connect analog ground electrically to GND close to the device.  
The device requires a bootstrap capacitor between BOOT and PH. A voltage on this capacitor that is  
below the minimum required by the BOOT UVLO forces the output to switch off until the capacitor  
recharges.  
BOOT  
13  
O
Error amplifier output, and input to the output-switch current comparator. Connect frequency-  
compensation components to this pin.  
COMP  
EN  
7
O
I
Enable pin, internal pullup-current source. Pull below 1.2 V to disable. Float to enable. One can use this  
pin to set the on-off threshold (adjust UVLO) with two additional resistors.  
15  
3
GND  
PH  
Power ground. Directly connect this pin electrically to the thermal pad under the device.  
4
10  
11  
12  
The source of the internal high-side power MOSFET, and drain of the internal low-side (synchronous)  
rectifier MOSFET  
O
An open-drain output; asserted low if output voltage is low due to thermal shutdown, overcurrent, over-  
or undervoltage, or EN shutdown.  
PWRGD  
RT/CLK  
SS/TR  
14  
8
O
I
Resistor-timing or external-clock input pin  
Slow start and tracking. An external capacitor connected to this pin sets the output-voltage rise time.  
Another use of this pin is for tracking.  
9
I
1
2
VIN  
I
Input supply voltage, 2.95 V to 6 V  
16  
6
VSENSE  
I
Inverting node of the transconductance (gm) error amplifier  
Connect the GND pin to the exposed thermal pad for proper operation. Connect this thermal pad to any  
internal PCB ground planes using multiple vias for good thermal performance.  
Thermal pad  
(1) I = input, O = output  
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English Data Sheet: SLVSDQ8  
 
 
TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
6 Specifications  
6.1 Absolute Maximum Ratings  
over operating free-air temperature range (unless otherwise noted)(1)  
MIN  
0.3  
0.3  
0.3  
0.3  
0.3  
0.3  
0.3  
0.3  
0.3  
0.6  
2  
MAX  
UNIT  
VIN  
7
7
EN  
BOOT  
PH + 7  
3
VSENSE  
Input voltage  
V
COMP  
3
PWRGD  
SS/TR  
7
3
RT/CLK  
BOOT-PH  
7
7
Output voltage  
PH  
7
V
PH 10-ns transient  
EN  
10  
100  
100  
100  
10  
Source current  
Sink current  
µA  
RT/CLK  
COMP  
µA  
mA  
µA  
°C  
PWRGD  
SS/TR  
100  
150  
125  
150  
Junction temperature, TJ  
Ambient temperature, TA  
Storage temperature, Tstg  
40  
40  
65  
°C  
°C  
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings  
only, and do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended  
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.  
6.2 ESD Ratings  
VALUE  
±2000  
±750  
UNIT  
Human body model (HBM), per AEC Q100-002(1)  
Electrostatic  
discharge  
V(ESD)  
Corner pins (1, 16, 4, 5, 8, 9, 12, and 13)  
Other pins  
V
Charged device model (CDM), per AEC  
Q100-011  
±500  
(1) AEC Q100-002 indicates HBM stressing is done in accordance with the ANSI/ESDA/JEDEC JS-001 specification.  
6.3 Recommended Operating Conditions  
over operating free-air temperature (unless otherwise noted)  
MIN  
2.95  
40  
NOM  
MAX  
6
UNIT  
V(VIN)  
TA  
Input voltage  
V
Operating ambient temperature  
125  
°C  
Copyright © 2023 Texas Instruments Incorporated  
English Data Sheet: SLVSDQ8  
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TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
6.4 Thermal Information  
TPS54388C-Q1  
THERMAL METRIC(1)  
RTE (WQFN)  
16 PINS  
43.5  
UNIT  
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  
46.1  
15.5  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
Junction-to-case(bottom) thermal resistance  
0.7  
ψJT  
15.5  
ψJB  
RθJC(bot)  
3.8  
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application  
report (SPRA953).  
6.5 Electrical Characteristics  
TJ = 40°C to 150°C, V(VIN) = 2.95 to 6 V (unless otherwise noted)  
DESCRIPTION  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
SUPPLY VOLTAGE (VIN PIN)  
VIN UVLO start  
VIN UVLO stop  
2.28  
2.45  
5.5  
2.5  
V
Internal undervoltage lockout threshold  
2.6  
Shutdown supply current  
Quiescent current, I(q)  
15  
V(EN) = 0 V, 25°C, 2.95 V V(VIN) 6 V  
μA  
μA  
515  
750  
V(SENSE) = 0.9 V, V(VIN) = 5 V, 25°C, Rt = 400 kΩ  
ENABLE AND UVLO (EN PIN)  
Rising  
1.25  
1.18  
Enable threshold  
Input current  
V
Falling  
Enable threshold + 50 mV  
1.6  
1.6  
μA  
Enable threshold 50 mV  
VOLTAGE REFERENCE (VSENSE PIN)  
Voltage reference  
0.79  
0.8 0.811  
V
2.95 V V(VIN) 6 V, 40°C <TJ < 150°C  
MOSFET  
V(BOOT-PH) = 5 V  
V(BOOT-PH) = 2.95 V  
V(VIN) = 5 V  
12  
16  
13  
17  
30  
30  
30  
30  
High-side switch resistance  
Low-side switch resistance  
mΩ  
mΩ  
V(VIN) = 2.95 V  
ERROR AMPLIFIER  
Input current  
2
nA  
Error-amplifier transconductance (gm)  
245  
2 μA < I(COMP) < 2 μA, V(COMP) = 1 V  
μS  
Error-amplifier transconductance (gm) during  
slow start  
2 μA < I(COMP) < 2 μA, V(COMP) = 1 V,  
V(VSENSE) = 0.4 V  
79  
μS  
Error amplifier source and sink  
V(COMP) = 1 V, 100-mV overdrive  
±20  
25  
μA  
COMP to high-side FET current gm  
S
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English Data Sheet: SLVSDQ8  
 
 
 
TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
TJ = 40°C to 150°C, V(VIN) = 2.95 to 6 V (unless otherwise noted)  
DESCRIPTION  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
CURRENT LIMIT  
Current limit threshold  
3.7  
6.5  
A
THERMAL SHUTDOWN  
Thermal shutdown  
168  
20  
°C  
°C  
Hysteresis  
TIMING RESISTOR AND EXTERNAL CLOCK (RT/CLK PIN)  
Switching frequency range using RT mode  
200  
400  
300  
75  
2000  
600  
kHz  
kHz  
kHz  
ns  
Switching frequency  
500  
Rt = 400 kΩ  
Switching frequency range using CLK mode  
Minimum CLK pulse duration  
RT/CLK voltage  
2000  
0.5  
1.6  
0.6  
V
Rt = 400 kΩ  
RT/CLK high threshold  
2.5  
V
RT/CLK low threshold  
0.4  
V
Delay from RT/CLK falling edge to PH rising  
edge  
Measure at 500 kHz with RT resistor in series with  
device pin  
90  
45  
ns  
PLL lock-in time  
Measure at 500 kHz  
μs  
PH (PH PIN)  
Measured at 50% point on PH, IO = 3 A  
75  
Minimum on-time  
ns  
Measured at 50% point on PH, V(VIN) = 6 V,  
IO = 0 A  
120  
Prior to skipping off pulses, BOOT-PH = 2.95 V,  
IO = 3 A  
Minimum off-time  
60  
ns  
Rise time  
V(VIN) = 6 V, 6 A  
V(VIN) = 6 V, 6 A  
2.25  
2
V/ns  
Fall time  
BOOT (BOOT PIN)  
BOOT charge resistance  
BOOT-PH UVLO  
V(VIN) = 5 V  
16  
V(VIN) = 2.95 V  
2.1  
V
SLOW START AND TRACKING (SS/TR PIN)  
Charge current  
V(SS/TR) = 0.4 V  
2
50  
μA  
mV  
V
SS/TR to VSENSE matching  
SS/TR to reference crossover  
SS/TR discharge voltage (overload)  
SS/TR discharge current (overload)  
V(SS/TR) = 0.4 V  
98% of normal reference voltage  
V(VSENSE) = 0 V  
1.1  
61  
mV  
µA  
V(VSENSE) = 0 V, V(SS/TR) = 0.4 V  
350  
SS discharge current (UVLO, EN, thermal  
fault)  
V(VIN) = 5 V, V(SS/TR) = 0.5 V  
1.9  
mA  
POWER GOOD (PWRGD PIN)  
VSENSE falling (Fault)  
VSENSE rising (Good)  
VSENSE rising (Fault)  
VSENSE falling (Good)  
VSENSE falling  
91  
93  
VSENSE threshold  
% Vref  
109  
107  
2
Hysteresis  
% Vref  
nA  
Output-high leakage  
On-resistance  
V(VSENSE) = Vref, V(PWRGD) = 5.5 V  
7
56  
100  
1.6  
Output low  
I(PWRGD) = 3 mA  
0.3  
0.65  
V
Minimum VIN for valid output  
V
V(PWRGD) < 0.5 V at 100 μA  
Copyright © 2023 Texas Instruments Incorporated  
English Data Sheet: SLVSDQ8  
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TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
6.6 Typical Characteristics  
525  
520  
515  
510  
505  
500  
495  
490  
485  
0.025  
0.023  
High-Side rDS(on), V(VIN) = 3.3 V  
Low-Side rDS(on), V(VIN) = 3.3 V  
0.021  
0.019  
0.017  
0.015  
0.013  
0.011  
0.009  
0.007  
0.005  
High-Side rDS(on), V(VIN) = 5 V  
Low-Side rDS(on), V(VIN) = 5 V  
480  
475  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
-50  
-25  
0
25  
50  
75  
100  
125  
150  
Junction Temperature (°C)  
Junction Temperature (°C)  
V(VIN) = 5 V  
Rt = 400 kΩ  
6-1. High-Side and Low-Side rDS(on) vs  
Temperature  
6-2. Frequency vs Temperature  
8
0.807  
7.5  
0.805  
0.803  
0.801  
0.799  
0.797  
0.795  
0.793  
0.791  
V
= 3.3 V  
7
6.5  
6
(VIN)  
5.5  
5
V
= 5 V  
(VIN)  
4.5  
4
3.5  
3
–50  
–25  
0
25  
50  
75  
100  
125  
150  
-50  
-25  
0
25  
50  
75  
100  
125  
150  
Junction Temperature (°C)  
Junction Temperature (°C)  
V(VIN) = 3.3 V  
6-3. High-Side Current Limit vs Temperature  
6-4. Voltage Reference vs Temperature  
2000  
1800  
1600  
1400  
1200  
1000  
800  
100  
V(VSENSE) Falling  
75  
V(VSENSE) Rising  
50  
25  
0
600  
400  
0
0.1  
0.2  
0.3  
0.4  
0.5  
0.6  
0.7  
0.8  
V(VSENSE) (V)  
200  
80  
180  
380  
480  
580  
680  
780  
880  
980  
280  
Resistance (kΩ)  
6-6. Switching Frequency vs V(VSENSE)  
6-5. Switching Frequency vs RT Resistance,  
Low-Frequency Range  
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English Data Sheet: SLVSDQ8  
 
 
TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
105  
100  
95  
310  
290  
270  
250  
230  
210  
90  
85  
80  
75  
70  
65  
190  
170  
60  
55  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
Junction Temperature (°C)  
Junction Temperature (°C)  
V(VIN) = 3.3 V  
V(VIN) = 3.3 V  
6-8. Transconductance (Slow Start) vs Junction  
6-7. Transconductance vs Temperature  
Temperature  
1.3  
1.29  
1.28  
–3  
–3.1  
–3.2  
–3.3  
–3.4  
–3.5  
–3.6  
–3.7  
–3.8  
V(VIN) = 3.3 V, rising  
1.27  
1.26  
1.25  
1.24  
1.23  
1.22  
1.21  
1.2  
V(VIN) = 3.3 V, falling  
1.19  
1.18  
1.17  
1.16  
1.15  
–3.9  
–4  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
Junction Temperature (°C)  
Junction Temperature (°C)  
6-9. EN Pin Voltage vs Temperature  
V(VIN) = 5 V  
V(EN) = Threshold + 50 mV  
6-10. EN Pin Current vs Temperature  
–1  
–1.4  
–1.2  
–1.4  
–1.6  
–1.8  
–2  
–1.6  
–1.8  
–2  
–2.2  
–2.4  
–2.6  
–2.2  
–2.4  
–2.6  
–2.8  
–3  
–2.8  
–3  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
–50 –30  
–10 10  
30  
50  
70  
90  
110  
130 150  
Junction Temperature (°C)  
Junction Temperature (°C)  
V(VIN) = 5 V  
V(VIN) = 5 V  
V(EN) = Threshold 50 mV  
6-12. Charge Current vs Temperature  
6-11. EN Pin Current vs Temperature  
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English Data Sheet: SLVSDQ8  
TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
2.8  
2.7  
2.6  
2.5  
2.4  
2.3  
2.2  
2.1  
8
7
6
5
4
3
2
UVLO Start Switching  
UVLO Stop Switching  
1
0
2
-50  
-25  
0
25  
50  
75  
100  
125  
150  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
Junction Temperature (°C)  
Junction Temperature (°C)  
V(VIN) = 3.3 V  
6-13. Input Voltage vs Temperature  
6-14. Shutdown Supply Current vs Temperature  
8
800  
7
6
5
4
3
2
700  
600  
500  
400  
300  
200  
1
0
3
3.5  
4
4.5  
5
5.5  
6
–50  
–25  
0
25  
50  
75  
100  
125  
150  
Input Voltage (V)  
Junction Temperature (°C)  
TJ = 25°C  
V(VIN) = 3.3 V  
6-15. Shutdown Supply Current vs Input Voltage  
6-16. VIN Supply Current vs Junction  
Temperature  
800  
700  
600  
500  
400  
110  
108  
106  
104  
102  
100  
98  
V(VSENSE) Rising,  
V(VSENSE) Falling,  
PWRGD Asserted  
PWRGD Deasserted  
V(VSENSE) Rising,  
PWRGD Asserted  
V(VSENSE) Falling,  
96  
PWRGD Deasserted  
94  
92  
300  
200  
90  
88  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
–50 –25  
0
25  
50  
75  
Junction Temperature (°C)  
100  
125  
150  
Junction Temperature (°C)  
TJ = 25°C  
V(VIN) = 5 V  
6-17. VIN Supply Current vs Input Voltage  
6-18. PWRGD Threshold vs Temperature  
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100  
100  
90  
80  
70  
60  
50  
40  
30  
20  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
10  
0
–50  
–25  
0
25  
50  
75  
100  
125  
150  
–50  
–25  
0
25  
50  
75  
100  
125  
150  
Junction Temperature (°C)  
V(VIN) = 5 V V(SS/TR) = 0.4 V  
Junction Temperature (°C)  
V(VIN) = 5 V  
6-20. SS/TR-to-VSENSE Offset vs Temperature  
6-19. PWRGD On-Resistance vs Temperature  
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7 Detailed Description  
7.1 Overview  
The TPS54388C-Q1 device is a 6-V, 3-A, synchronous step-down (buck) converter with two integrated n-  
channel MOSFETs. To improve performance during line and load transients, the device implements a constant-  
frequency, peak-current-mode control, which reduces output capacitance and simplifies external frequency-  
compensation design. The wide switching-frequency range of 200 kHz to 2000 kHz allows for efficiency and size  
optimization when selecting the output-filter components. A resistor to ground on the RT/CLK pin sets the  
switching frequency. The device has an internal phase-lock loop (PLL) on the RT/CLK pin that synchronizes the  
power-switch turnon to a falling edge of an external system clock.  
The TPS54388C-Q1 device has a typical default start-up voltage of 2.45 V. The EN pin has an internal pullup  
current source that one can use to adjust the input-voltage undervoltage lockout (UVLO) with two external  
resistors. In addition, the pullup current provides a default condition, allowing the device to operate when the EN  
pin is floating. The total operating current for the device is typically 515 μA when not switching and under no  
load. With the device disabled, the supply current is typically 5.5 μA.  
The integrated 12-mMOSFETs allow for high-efficiency power-supply designs with continuous output currents  
up to 3 A.  
The TPS54388C-Q1 device reduces the external component count by integrating the boot recharge diode. A  
capacitor between the BOOT and PH pins supplies the bias voltage for the integrated high-side MOSFET. A  
UVLO circuit monitors the boot-capacitor voltage and turns off the high-side MOSFET when the voltage falls  
below a preset threshold. This BOOT circuit allows the TPS54388C-Q1 device to operate approaching 100%  
duty cycle. The lower limit for stepping down the output voltage is the 0.8-V reference.  
The TPS54388C-Q1 device has a power-good comparator (PWRGD) with 2% hysteresis.  
The TPS54388C-Q1 device minimizes excessive output overvoltage transients by taking advantage of the  
overvoltage power-good comparator. A regulated output voltage exceeding 109% of the nominal voltage  
activates the overvoltage comparator, turning off the high-side MOSFET and masking it from turning on until the  
output voltage is lower than 107% of the nominal voltage.  
A use of the SS/TR (slow start pr tracking) pin is to minimize inrush currents or provide power-supply sequencing  
during power up. Couple a small-value capacitor to the pin for slow start. Discharging the SS/TR pin before the  
output powers up ensures a repeatable restart after an overtemperature fault, UVLO fault, or disabled condition.  
The use of a frequency foldback circuit reduces the switching frequency during start-up and overcurrent fault  
conditions to help limit the inductor current.  
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7.2 Functional Block Diagram  
PWRGD  
EN  
VIN  
i(1)  
i(hys)  
Shutdown  
Thermal  
Shutdown  
UVLO  
Enable  
Comparator  
91%  
Logic  
Shutdown  
Shutdown  
Logic  
109%  
Enable  
Threshold  
Boot  
Charge  
Voltage  
Reference  
Boot  
UVLO  
Minimum  
COMP Clamp  
Current  
Sense  
Error  
Amplifier  
PWM  
Comparator  
VSENSE  
SS/TR  
BOOT  
Logic and PWM  
Latch  
Shutdown  
Logic  
Slope  
Compensation  
S
PH  
COMP  
Frequency  
Shift  
Overload  
Recovery  
Maximum  
Clamp  
Oscillator  
With PLL  
GND  
TPS54388C-Q1 Block Diagram  
RT/CLK  
AGND  
Thermal Pad  
7.3 Feature Description  
7.3.1 Fixed-Frequency PWM Control  
The TPS54388C-Q1 device uses an adjustable fixed-frequency, peak-current-mode control. An error amplifier,  
which drives the COMP pin, compares the output voltage through external resistors on the VSENSE pin to an  
internal voltage reference. An internal oscillator initiates the turnon of the high-side power switch. The device  
compares the error-amplifier output to the high-side power-switch current. When the sensed voltage derived  
from the power-switch current reaches the COMP voltage level, the high-side power switch turns off and the low-  
side power switch turns on. The COMP pin voltage increases and decreases as the output current increases and  
decreases. The device implements a current limit by clamping the COMP pin voltage to a maximum level, and  
also implements a minimum clamp for improved transient-response performance.  
7.3.2 Slope Compensation and Output Current  
The TPS54388C-Q1 device adds a compensating ramp to the switch-current signal. This slope compensation  
prevents sub-harmonic oscillations as duty cycle increases. The available peak inductor current remains  
constant over the full duty-cycle range.  
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7.3.3 Bootstrap Voltage (BOOT) and Low-Dropout Operation  
The TPS54388C-Q1 device has an integrated boot regulator and requires a small ceramic capacitor between the  
BOOT and PH pins to provide the gate-drive voltage for the high-side MOSFET. The value of the ceramic  
capacitor should be 0.1 μF. TI recommends a ceramic capacitor with an X7R- or X5R-grade dielectric with a  
voltage rating of 10 V or higher because of the stable characteristics over temperature and voltage.  
The TPS54388C-Q1 design improves dropout by operating at 100% duty cycle as long as the BOOT-to-PH pin  
voltage is greater than 2.2 V. A UVLO circuit turns off the high-side MOSFET, allowing for the low-side MOSFET  
to conduct when the voltage from BOOT to PH drops below 2.2 V. Because the supply current sourced from the  
BOOT pin is low, the high-side MOSFET can remain on for more switching cycles than are required to refresh  
the capacitor. Thus, the effective duty cycle of the switching regulator is high.  
7.3.4 Error Amplifier  
The TPS54388C-Q1 device has a transconductance amplifier that it uses as an error amplifier. The error  
amplifier compares the VSENSE voltage to the lower of the SS/TR pin voltage or the internal 0.8-V voltage  
reference. The transconductance of the error amplifier is 245 μS during normal operation. When the voltage of  
VSENSE pin is below 0.8 V and the device is regulating using the SS/TR voltage, the gm is typically greater than  
79 μS, but less than 245 μS.  
7.3.5 Voltage Reference  
The voltage reference system produces a precise ±1% voltage reference over temperature by scaling the output  
of a temperature-stable band-gap circuit. The band-gap and scaling circuits produce 0.8 V at the non-inverting  
input of the error amplifier.  
7.4 Device Functional Modes  
7.4.1 Adjusting the Output Voltage  
A resistor divider from the output node to the VSENSE pin sets the output voltage. TI recommends using divider  
resistors with 1% tolerance or better. Start with 100 kfor the R1 resistor and use 方程式 1 to calculate R2. To  
improve efficiency at light loads, consider using larger-value resistors. If the values are too high, the regulator is  
more susceptible to noise, and voltage errors from the VSENSE input current are noticeable.  
æ
ç
è
ö
÷
ø
0.8 V  
R2 = R1´  
VO - 0.8 V  
(1)  
TPS54388C-Q1  
V
O
R1  
R2  
VSENSE  
-
0.8 V  
+
7-1. Voltage-Divider Circuit  
7.4.2 Enable Functionality and Adjusting Undervoltage Lockout  
The VIN pin voltage on the VIN pin falling below 2.6 V disables the TPS54388C-Q1 device. If an application  
requires a higher undervoltage lockout (UVLO), use the EN pin as shown in 7-2 to adjust the input voltage  
UVLO by using two external resistors. TI recommends using the EN resistors to set the UVLO falling threshold  
(V(STOP)) above 2.6 V. Set the rising threshold (V(START)) to provide enough hysteresis to allow for any input  
supply variations. The EN pin has an internal pullup current source that provides the default condition of  
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TPS54388C-Q1 operation when the EN pin floats. Once the EN pin voltage exceeds 1.25 V, the circuitry adds an  
additional 1.6 μA of hysteresis. Pulling the EN pin below 1.18 V removes the 1.6 μA. This additional current  
facilitates input voltage hysteresis.  
TPS54388C-Q1  
I
hys  
VIN  
1.6 mA  
I
1
R1  
R2  
1.6 mA  
+
EN  
-
7-2. Adjustable Undervoltage Lockout  
æ
ç
ç
è
ö
÷
÷
ø
V
(ENFALLING)  
V
- V  
(STOP)  
(START)  
V
(ENRISING)  
R1 =  
æ
ç
(1) ç  
è
ö
÷
÷
ø
V
(ENFALLING)  
I
1-  
+ I  
(hys)  
V
(ENRISING)  
(2)  
where  
V(ENFALLING) = 1.18 V  
V(ENRISING) = 1.25 V  
I(1) = 1.6 µA  
I(hys) = 1.6 µA  
R1´ V  
(ENFALLING)  
R2 =  
V
(STOP) - V(ENFALLING) + R1´(I(1) + I(hys)  
)
(3)  
7.4.3 Slow-Start or Tracking Pin  
The TPS54388C-Q1 device regulates to the lower of the SS/TR pin and the internal reference voltage. A  
capacitor on the SS/TR pin to ground implements a slow-start time. The TPS54388C-Q1 device has an internal  
pullup current source of 2 μA, which charges the external slow-start capacitor. 方程式 4 calculates the required  
slow-start capacitor value, where t(SS/TR) is the desired slow start time in ms, I(SS/TR) is the internal slow start  
charging current of 2 μA, and Vref is the internal voltage reference of 0.8 V.  
t(SS/TR) (ms) ´ I(SS/TR) (mA)  
C(SS/TR) (nF) =  
V
(V)  
ref  
(4)  
If during normal operation, VIN goes below UVLO, the EN pin goes below 1.2 V, or a thermal shutdown event  
occurs, the TPS54388C-Q1 device stops switching. On VIN going above UVLO, the release or pulling high of  
EN, or exit from a thermal shutdown, SS/TR discharges to below 60 mV before re-initiation of a power-up  
sequence. The VSENSE voltage follows the SS/TR pin voltage with a 50-mV offset up to 85% of the internal  
voltage reference. When the SS/TR voltage is greater than 85% of the internal reference voltage, the offset  
increases as the effective system reference transitions from the SS/TR voltage to the internal voltage reference.  
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7.4.4 Sequencing  
One can implement many of the common power-supply sequencing methods using the SS/TR, EN, and PWRGD  
pins. Implementation of the sequential method uses an open-drain or open-collector output of the power-on-  
reset pin of another device. 7-3 shows the sequential method. Couple the power-good to the EN pin on the  
TPS54388C-Q1 device to enable the second power supply once the primary supply reaches regulation.  
One can accomplish ratiometric start-up by connecting the SS/TR pins together. The regulator outputs ramp up  
and reach regulation at the same time. When calculating the slow-start time, double the pullup current source in  
方程4. 7-5 shows the ratiometric method.  
TPS54388C-Q1  
PWRGD  
EN  
EN  
EN1  
SS/TR  
SS/TR  
EN2  
PWRGD  
VO(1)  
7-3. Sequential Start-Up Sequence  
VO(2)  
7-4. Sequential Start-Up Using EN and PWRGD  
TPS54388C-Q1  
EN1  
SS/TR1  
EN  
PWRGD1  
SS  
TPS54388C-Q1  
VO(1)  
EN2  
VO(2)  
SS/TR2  
PWRGD2  
7-6. Ratiometric Start-Up With VO(1) Leading  
7-5. Schematic for Ratiometric Start-Up  
VO(2)  
Sequence  
One can implement ratiometric and simultaneous power-supply sequencing by connecting the resistor network  
of R1 and R2 shown in 7-7 to the output of the power supply that requires tracking, or to another voltage  
reference source. Using 方程式 5 and 方程式 6, one can calculate the tracking resistors to initiate VO(2) slightly  
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before, after, or at the same time as VO(1). VO(1) VO(2) is 0 V for simultaneous sequencing. Including V(ssoffset)  
and I(SS/TR) as variables in the equations minimizes the effect of the inherent SS/TR-to-VSENSE offset (V(ssoffset)  
)
in the slow-start circuit and the offset created by the pullup current source (I(ss)) and tracking resistors. Because  
the SS/TR pin requires pulling below 60 mV before starting after an EN, UVLO, or thermal-shutdown fault, select  
the tracking resistors carefully to ensure the device can restart after a fault. Make sure the calculated R1 value  
from 方程式 5 is greater than the value calculated in 方程式 7 to ensure the device can recover from a fault. As  
the SS/TR voltage becomes more than 85% of the nominal reference voltage, V(ssoffset) becomes larger as the  
slow-start circuits gradually hand off the regulation reference to the internal voltage reference. The SS/TR pin  
voltage must be greater than 1.1 V for a complete handoff to the internal voltage reference as shown in 7-6.  
VO(1)  
V
(ssoffset)  
R1 =  
´
V
I(SS/TR)  
ref  
(5)  
V
´ R1  
ref  
R2 =  
VO(1) - V  
ref  
(6)  
(7)  
R1 > 2930´ VO(1) - 145 ´ (VO(1) - VO(2)  
)
TPS54388C-Q1  
BOOT1  
EN1  
PH1  
EN1  
SS2  
VO(1)  
SS/TR1  
PWRGD1  
VO(1)  
VO(2)  
TPS54388C-Q1  
BOOT2  
R1  
R2  
EN2  
PH2  
VO(2)  
SS/TR2  
VSENSE2  
PWRGD2  
7-8. Ratiometric Start-Up Using Coupled SS/TR  
Pins  
7-7. Ratiometric and Simultaneous Start-Up  
Sequence  
7.4.5 Constant Switching Frequency and Timing Resistor (RT/CLK Pin)  
The switching frequency of the TPS54388C-Q1 device is adjustable over a wide range from 200 kHz to 2000  
kHz by placing a resistor on the RT/CLK pin with a value calculated by 方程式 8. An internal amplifier holds this  
pin at a fixed voltage when using an external resistor to ground to set the switching frequency. The voltage on  
RT/CLK is typically 0.5 V. To determine the timing resistance for a given switching frequency, use 方程8 or the  
curve in 6-5.  
247 530 (MW/s)  
1.0533  
Rt kW =  
( )  
f(SW)  
kHz  
(
)
(8)  
(9)  
131 904 (MW/s)  
0.9492  
f
kHz =  
( )  
(SW)  
Rt  
kW  
( )  
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To reduce the solution size, one would typically set the switching frequency as high as possible, but consider  
tradeoffs of the efficiency, maximum input voltage, and minimum controllable on-time.  
The minimum controllable on-time is typically 60 ns at full-current load and 120 ns at no load, and limits the  
maximum operating input voltage or output voltage.  
7.4.6 Overcurrent Protection  
The TPS54388C-Q1 device implements a cycle-by-cycle current limit. During each switching cycle, the device  
compares a voltage derived from the high-side switch current to the voltage on the COMP pin. When the  
instantaneous switch-current voltage intersects the COMP voltage, the high-side switch turns off. During  
overcurrent conditions that pull the output voltage low, the error amplifier responds by driving the COMP pin  
high, increasing the switch current. An internal clamp on the error-amplifier output functions as a switch-current  
limit.  
7.4.7 Frequency Shift  
To operate at high switching frequencies and provide protection during overcurrent conditions, the TPS54388C-  
Q1 device implements a frequency shift. Without this frequency shift, during an overcurrent condition the low-  
side MOSFET might not turn off long enough to reduce the current in the inductor, causing a current runaway.  
With frequency shift, during an overcurrent condition there is a switching-frequency reduction from 100% to 50%,  
then 25%, as the voltage decreases from 0.8 V to 0 V on the VSENSE pin. The frequency shift allows the low-  
side MOSFET to be off long enough to decrease the current in the inductor. During start-up, the switching  
frequency increases as the voltage on VSENSE increases from 0 V to 0.8 V. See 6-6 for details.  
7.4.8 Reverse Overcurrent Protection  
The TPS54388C-Q1 device implements low-side current protection by detecting the voltage across the low-side  
MOSFET. When the converter sinks current through its low-side FET, the control circuit turns off the low-side  
MOSFET if the reverse current is typically more than 4.5 A. By implementing this additional protection scheme,  
the converter is able to protect itself from excessive current during power cycling and start-up into pre-biased  
outputs.  
7.4.9 Synchronize Using the RT/CLK Pin  
The RT/CLK pin synchronizes the converter to an external system clock. See 7-9. To implement the  
synchronization feature in a system, connect a square wave to the RT/CLK pin with an on-time of at least 75 ns.  
If the square wave pulls the pin above the PLL upper threshold, a mode change occurs, and the pin becomes a  
synchronization input. The CLK mode disables the internal amplifier, and the pin becomes a high-impedance  
clock input to the internal PLL. Stopping the clocking edges re-enables the internal amplifier, and the mode  
returns to the frequency set by the resistor. The square-wave amplitude at this pin must transition lower than 0.6  
V and higher than 1.6 V, typically. The synchronization frequency range is 300 kHz to 2000 kHz. The rising edge  
of PH synchronizes to the falling edge of the RT/CLK pin.  
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TPS54388C-Q1  
SYNC Clock = 2 V/div  
RT/CLK  
PLL  
PH = 2 V/div  
Clock  
Source  
Rt  
7-9. Synchronizing to a System Clock  
Time = 500 ns/div  
7-10. Plot of Synchronizing to a System Clock  
7.4.10 Power Good (PWRGD Pin)  
The output of the PWRGD pin is an open-drain MOSFET. The output goes low when the VSENSE voltage enters  
the fault condition by falling below 91% or rising above 109% of the nominal internal reference voltage. There is  
a 2% hysteresis on the threshold voltage, so when the VSENSE voltage rises to the good condition above 93%  
or falls below 107% of the internal voltage reference, the PWRGD output MOSFET turns off. TI recommends  
using a pullup resistor between the values of 1 kand 100 kto a voltage source that is 6 V or less. PWRGD is  
in a valid state once the VIN input voltage is greater than 1.1 V.  
7.4.11 Overvoltage Transient Protection  
The TPS54388C-Q1 device incorporates an overvoltage transient protection (OVTP) circuit to minimize voltage  
overshoot when recovering from output fault conditions or strong unload transients. The OVTP feature minimizes  
the output overshoot by implementing a circuit to compare the VSENSE pin voltage to the OVTP threshold,  
which is 109% of the internal voltage reference. If the VSENSE pin voltage goes higher than the OVTP  
threshold, the high-side MOSFET turns off, preventing current from flowing to the output and minimizing output  
overshoot. When the VSENSE voltage drops lower than the OVTP threshold, the high-side MOSFET turns on in  
the next clock cycle.  
7.4.12 Thermal Shutdown  
The device implements an internal thermal shutdown to protect itself if the junction temperature exceeds 168°C.  
The thermal shutdown forces the device to stop switching when the junction temperature exceeds the thermal  
trip threshold. Once the die temperature decreases below 148°C, the device reinitiates the power-up sequence  
by discharging the SS/TR pin to below 60 mV. The thermal shutdown hysteresis is 20°C.  
7.4.13 Small-Signal Model for Loop Response  
7-11 shows an equivalent model for the TPS54388C-Q1 control loop, which one can model in a circuit-  
simulation program to check frequency response and dynamic load response. The error amplifier is a  
transconductance amplifier with a gm of 245 μS. One can model the error amplifier using an ideal voltage-  
controlled current source. The resistor R0 and capacitor C0 model the open-loop gain and frequency response  
of the amplifier. The 1-mV ac voltage source between nodes a and b effectively breaks the control loop for the  
frequency-response measurements. Plotting a over c vs frequency shows the small-signal response of the  
frequency compensation. Plotting a over b vs frequency shows the small-signal response of the overall loop.  
Check the dynamic loop response by replacing R(L) with a current source that has the appropriate load-step  
amplitude and step rate in a time-domain analysis.  
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PH  
VO  
Power Stage  
25 S  
a
b
R(ESR)  
R1  
R(L)  
COMP  
c
VSENSE  
0.8 V  
C(OUT)  
R3  
C1  
C0  
gm  
245 µS  
R0  
C2  
R2  
7-11. Small-Signal Model for Loop Response  
7.4.14 Simple Small-Signal Model for Peak-Current-Mode Control  
7-11 is a simple small-signal model that one can use to understand how to design the frequency  
compensation. A voltage-controlled current source (duty-cycle modulator) supplying current to the output  
capacitor and load resistor approximates the TPS54388C-Q1 power stage. 方程式 10 shows the control-to-  
output transfer function, which consists of a dc gain, one dominant pole, and one ESR zero. The quotient of the  
change in switch current divided by the change in COMP pin voltage (node c in 7-11) is the power-stage  
transconductance. The gm for the TPS54388C-Q1 device is 25 S. The low-frequency gain of the power-stage  
frequency response is the product of the transconductance and the load resistance as shown in 方程式 11. As  
the load current increases and decreases, the low-frequency gain decreases and increases, respectively. This  
variation with load may seem problematic at first glance, but the dominant pole moves with load current (see 方  
程式 12). The dashed line in the right half of 7-12 highlights the combined effect. As the load current  
decreases, the gain increases and the pole frequency lowers, keeping the 0-dB crossover frequency the same  
for varying load conditions, which makes it easier to design the frequency compensation.  
VO  
Adc  
VC  
R
ESR  
fp  
R
L
gm  
ps  
C
OUT  
fz  
7-12. Simple Small-Signal Model and Frequency Response for Peak-Current-Mode Control  
æ
ö
s
1+  
1+  
ç
ç
è
÷
÷
ø
2p × f(z)  
VO  
= A(dc)  
´
V
æ
ç
ç
è
ö
÷
÷
ø
(C)  
s
2p × f(p)  
(10)  
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A(dc) = gm(ps) ´ R(L)  
(11)  
1
f(p)  
=
C
(OUT) ´ R(L) ´ 2p  
(12)  
(13)  
1
f(z)  
=
C
(OUT) ´ R(ESR) ´ 2p  
7.4.15 Small-Signal Model for Frequency Compensation  
The TPS54388C-Q1 device uses a transconductance amplifier for the error amplifier and readily supports two of  
the commonly used frequency-compensation circuits. 7-13 shows the compensation circuits. The most-likely  
implementation of Type 2B circuits is in high-bandwidth power-supply designs using low-ESR output capacitors.  
Type 2A contains one additional high-frequency pole to attenuate high-frequency noise.  
VO  
R1  
VSENSE  
Type 2A  
Type 2B  
COMP  
gm  
ea  
CO  
Vref  
R3  
C1  
C2  
R3  
RO  
R2  
5pF  
C1  
7-13. Types of Frequency Compensation  
The design guidelines for TPS54388C-Q1 loop compensation are as follows:  
1. Calculate the modulator pole, f(p,mod), and the ESR zero, f(z,mod), using 方程14 and 方程15. The output  
capacitor (C(OUT)) may require derating if the output voltage is a high percentage of the capacitor rating. Use  
the manufacturer information for the capacitor to derate the capacitor value. Use 方程16 and 方程17 to  
estimate a starting point for the crossover frequency, f(c). 方程16 is the geometric mean of the modulator  
pole and the ESR zero, and 方程17 is the mean of the modulator pole and the switching frequency. Use  
the lower value of 方程16 or 方程17 as the maximum crossover frequency.  
IO(max)  
f(p,mod)  
=
2p´ VO ´ C(OUT)  
(14)  
1
f(z,mod)  
=
2p´R(ESR) ´ C(OUT)  
(15)  
(16)  
f(c)  
=
f
(p,mod) ´ f(z,mod)  
f(SW)  
f(c)  
=
f(p,mod)  
´
2
(17)  
(18)  
2. Determine R3 using 方程18.  
2p´ f(c) ´ VO ´ C(OUT)  
R3 =  
g
m(ea) ´ V ´ gm(ps)  
ref  
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where  
gm(ea) is the amplifier gain (245 μS)  
gm(ps) is the power-stage gain (25 S)  
3. Place a compensation zero at the dominant pole:  
1
f(p)  
=
C
(OUT) ´ R(L) ´ 2p  
(19)  
(20)  
4. Determine C1 using 方程20.  
R
(L) ´ C(OUT)  
C1 =  
R3  
vertical spacer  
5. C2 is optional. Use it, if necessary, to cancel the zero from the ESR of C(OUT)  
.
R
(ESR) ´ C(OUT)  
C2 =  
R3  
(21)  
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8 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。  
8.1 Application Information  
Details on how to use this device in automotive applications appear throughout this device specification. The  
following sections provide the typical application use case with equations and methods on selecting the external  
components, as well as layout guidelines.  
8.2 Typical Application  
TPS54388C-Q1  
8-1. High-Frequency, 1.8-V Output Power-Supply Design With Adjusted UVLO  
8.2.1 Design Requirements  
This example details the design of a high-frequency switching-regulator design using ceramic output capacitors.  
To start the design process, it is necessary to know a few parameters. Determination of these parameters is  
typically at the system level. For this example, start with the following known parameters:  
8-1. Design Parameters  
DESIGN PARAMETER  
EXAMPLE VALUE  
Output voltage  
1.8 V  
Transient response, 1-A to 2-A load step  
Maximum output current  
Input voltage  
ΔV(out) = 5%  
3 A  
5 V nominal, 3 V to 5 V  
< 30 mV p-p  
1000 kHz  
Output-voltage ripple  
Switching frequency, f(sw)  
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8.2.2 Detailed Design Procedure  
8.2.2.1 Selecting the Switching Frequency  
The first step is to decide on a switching frequency for the regulator. Typically, one would choose the highest  
switching frequency possible to produce the smallest solution size. The high switching frequency allows for  
lower-valued inductors and smaller output capacitors compared to a power supply that switches at a lower  
frequency. However, the highest switching frequency causes extra switching losses, which hurt the converter  
performance. The converter is capable of running from 200 kHz to 2 MHz. Unless a small solution size is an  
ultimate goal, select a moderate switching frequency of 1 MHz to achieve both a small solution size and high-  
efficiency operation. Using 方程式 8, calculate R5 to be 180 k. Choose a standard 1% 182-kvalue for the  
design.  
8.2.2.2 Output Inductor Selection  
The inductor selected works for the entire TPS54388C-Q1 input-voltage range. To calculate the value of the  
output inductor, use 方程式 22. The k(IND) coefficient represents the amount of inductor ripple current relative to  
the maximum output current. The output capacitor filters the inductor ripple current. Therefore, choosing high  
inductor ripple currents impacts the selection of the output capacitor, because the output capacitor must have a  
ripple-current rating equal to or greater than the inductor ripple current. In general, the inductor ripple value is at  
the discretion of the designer; however, k(IND) is normally from 0.1 to 0.3 for the majority of applications.  
For this design example, use k(IND) = 0.3, and the inductor value calculates to be 1.36 μH. For this design,  
choose the nearest standard value of 1.5 μH. For the output-filter inductor, it is important not to exceed the rms-  
current and saturation-current ratings. Find the rms and peak inductor current using 方程24 and 方程25.  
For this design, the rms inductor current is 3.01 A and the peak inductor current is 3.72 A. The chosen inductor  
is a Coilcraft XLA4020-152ME_ or equivalent. It has a saturation current rating 0f 9.6 A and an RMS current  
rating of 7.5 A.  
The current flowing through the inductor is the inductor ripple current plus the output current. During power up,  
faults, or transient load conditions, the inductor current can increase above the calculated peak inductor current  
level calculated previously. In transient conditions, the inductor current can increase up to the switch-current limit  
of the device. For this reason, the most conservative approach is to specify an inductor with a saturation current  
rating equal to or greater than the switch-current limit rather than the peak inductor current.  
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VI(max) - VO  
VO  
L1 =  
´
I
O ´ k(IND)  
V
I(max) ´ f(SW)  
(22)  
(23)  
VI(max) - VO  
VO  
I(ripple)  
=
´
L1  
V
I(max) ´ f(SW)  
æ
ö2  
÷
÷
ø
VO ´ (VI(max) - VO )  
VI(max) ´ L1 ´ f(SW)  
1
2
I(Lrms)  
=
IO  
+
´ ç  
ç
è
12  
(24)  
(25)  
I(ripple)  
I(Lpeak) = IO +  
8.2.2.3 Output Capacitor  
2
Three primary considerations must be considered for selecting the value of the output capacitor. The output  
capacitor determines the modulator pole, the output voltage ripple, and how the regulator responds to a large  
change in load current. Base the output-capacitance selection on the most-stringent of these three criteria.  
The desired response to a large change in the load current is the first criterion. The output capacitor must supply  
the load with current when the regulator cannot. This situation would occur if there are desired hold-up times for  
the regulator where the output capacitor must hold the output voltage above a certain level for a specified  
amount of time after removal of the input power. The regulator is temporarily not able to supply sufficient output  
current if there is a large, fast increase in the current requirement of the load, such as transitioning from no load  
to a full load. The regulator usually requires two or more clock cycles for the control loop to see the change in  
load current and output voltage and then adjust the duty cycle to react to the change. The output capacitor must  
be large enough to supply the extra current to the load until the control loop responds to the load change. The  
output capacitance must be large enough to supply the difference in current for two clock cycles while only  
allowing a tolerable amount of droop in the output voltage. 方程式 26 shows the minimum output capacitance  
necessary to meet this requirement.  
For this example, the specification for transient-load response is a 5% change in VO for a load step from 0 A (no  
load) to 1.5 A (50% load). For this example, ΔIO = 1.5 A 0 A = 1.5 A and ΔVO = 0.05 × 1.8 V = 0.09 V. Using  
these numbers gives a minimum capacitance of 33 μF. This value does not take the ESR of the output capacitor  
into account in the output voltage change. For ceramic capacitors, the ESR is usually small enough to ignore in  
this calculation.  
方程式 27 calculates the minimum output capacitance needed to meet the output-voltage ripple specification. In  
this case, the maximum output-voltage ripple is 30 mV. Under this requirement, 方程27 yields 2.3 µF.  
2 ´ DIO  
C(OUT)  
>
f
(SW) ´ DVO  
(26)  
where  
• ΔIO is the change in output current  
f(SW) is the regulator switching frequency  
• ΔVO is the allowable change in the output voltage  
1
1
C(OUT)  
>
´
VO(ripple)  
8´ f(SW)  
I(ripple)  
(27)  
where  
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f(SW) is the switching frequency  
VO(ripple) is the maximum allowable output voltage ripple  
I(ripple) is the inductor ripple current  
Use 方程式 28 to calculate the maximum ESR an output capacitor can have to meet the output-voltage ripple  
specification. 方程式 28 indicates the ESR should be less than 55 m. In this case, the ESR of the ceramic  
capacitor is much less than 55 m.  
Factoring in additional capacitance deratings for aging, temperature, and dc bias increases this minimum value.  
For this example, use two 22-μF, 10-V X5R ceramic capacitors with 3 mof ESR.  
Capacitors generally have limits to the amount of ripple current they can handle without failing or producing  
excess heat. Select an output capacitor that can support the inductor ripple current. Some capacitor data sheets  
specify the root-mean-square (rms) value of the maximum ripple current. Use 方程式 29 to calculate the rms  
ripple current that the output capacitor must support. For this application, 方程29 yields 333 mA.  
VO(ripple)  
R(ESR)  
<
I(ripple)  
(28)  
(29)  
VO ´ (VI(max) - VO )  
12 ´ VI(max) ´ L1 ´ f(SW)  
I(Co,rms)  
=
8.2.2.4 Input Capacitor  
The TPS54388C-Q1 device requires a high-quality ceramic, type X5R or X7R, input decoupling capacitor with at  
least 4.7 μF of effective capacitance, and in some applications a bulk capacitance. The effective capacitance  
includes any dc bias effects. The voltage rating of the input capacitor must be greater than the maximum input  
voltage. The capacitor must also have a ripple-current rating greater than the maximum input-current ripple of  
the TPS54388C-Q1 device. Calculate the input ripple current using 方程30.  
The value of a ceramic capacitor varies significantly over temperature and the amount of dc bias applied to the  
capacitor. Minimize the capacitance variations due to temperature by selecting a dielectric material that is stable  
over temperature. X5R and X7R ceramic dielectrics are the usual selection for power regulator capacitors  
because they have a high capacitance-to-volume ratio and are fairly stable over temperature. The output-  
capacitor selection must also take dc bias into account. The capacitance value of a capacitor decreases as the  
dc bias across that capacitor increases.  
This example design requires a ceramic capacitor with at least a 10-V voltage rating to support the maximum  
input voltage. For this example, the selection is one 10-μF 10-V and one 0.1-μF 10-V capacitor in parallel. The  
input capacitance value determines the input ripple voltage of the regulator. Calculate the input voltage ripple  
using 方程式 31. Using the design example values, IO(max) = 3 A, C(IN) = 10 μF, and f(SW) = 1 MHz, yields an  
input voltage ripple of 76 mV and an rms input ripple current of 1.47 A.  
V
(
- VO  
)
VO  
I(min)  
I(Ci,rms) = IO  
´
´
VI(min)  
VI(min)  
(30)  
(31)  
I
O(max) ´ 0.25  
DVI =  
C(IN) ´ f(SW)  
8.2.2.5 Slow-Start Capacitor  
The slow-start capacitor determines the minimum amount of time it takes for the output voltage to reach its  
nominal programmed value during power up. Slow start is useful if a load requires a controlled rate of voltage  
slew. Another use for slow start is if the output capacitance is large and would require large amounts of current  
to charge the capacitor quickly to the output-voltage level. The large current necessary to charge the capacitor  
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may make the TPS54388C-Q1 device reach the current limit, or excessive current draw from the input power  
supply may cause the input voltage rail to sag. Limiting the output-voltage slew rate solves both of these  
problems.  
Calculate the slow-start capacitor value using 方程式 32. For the example circuit, the slow-start time is not too  
critical because the output-capacitor value is 44 μF, which does not require much current to charge to 1.8 V.  
The example circuit has the slow-start time set to an arbitrary value of 4 ms, which requires a 10-nF capacitor. In  
the TPS54388C-Q1 device, I(SS/TR) is 2.2 μA and Vref is 0.8 V.  
t(SS) (ms) ´ I(SS/TR) (mA)  
C(SS) (nF) =  
V
(V)  
ref  
(32)  
8.2.2.6 Bootstrap Capacitor Selection  
Connect a 0.1-μF ceramic capacitor between the BOOT and PH pins for proper operation. TI recommends  
using a ceramic capacitor with X5R or better-grade dielectric. The capacitor should have a 10-V or higher  
voltage rating.  
8.2.2.7 Output-Voltage and Feedback-Resistor Selection  
For the example design, the R6 selection is 100 k. Using 方程式 33, calculate R7 as 80 k. The nearest  
standard 1% resistor is 80.5 k.  
V
ref  
R7 =  
´ R6  
VO - V  
ref  
(33)  
Because of the internal design of the TPS54388C-Q1 device, there is a minimum output-voltage limit for any  
given input voltage. The output voltage can never be lower than the internal voltage reference of 0.8 V. Above  
0.8 V, an output voltage limit may exist due to the minimum controllable on-time. In this case, 方程式 34 gives  
the minimum output voltage:  
V
O(min) = t(ONmin) ´ f(SWmax) ´ VI(max) - IO(min) ´ 2´ rDS(on) - I  
(
´ R(L) + rDS(on)  
O(min)  
)
(
)
(34)  
where  
VO(min) = minimum achievable output voltage  
t(ONmin) = minimum controllable on-time (65 ns typical, 120 ns with no load)  
f(SWmax) = maximum switching frequency, including tolerance  
VI(max) = maximum input voltage  
IO(min) = minimum load current  
rDS(on) = minimum high-side MOSFET on-resistance (15 m19 m)  
R(L) = series resistance of output inductor  
There is also a maximum achievable output voltage, which is limited by the minimum off-time. 方程式 35 gives  
the maximum output voltage.  
VO(max) = 1- t(OFFmax) ´ f(SWmax) ´ V  
(
- IO(max) ´ 2´rDS(on) - I  
)
´ R(L) + rDS(on)  
O(max)  
) ( I(min)  
(
)
(35)  
where  
VO(max) = maximum achievable output voltage  
t(OFFmax) = maximum off-time (60 ns, typical)  
f(SWmax) = maximum switching frequency, including tolerance  
VI(min) = minimum input voltage  
IO(max) = maximum load current  
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rDS(on) = maximum high-side MOSFET on-resistance (19 m30 m)  
R(L) = series resistance of output inductor  
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8.2.2.8 Compensation  
The industry uses several techniques to compensate dc-dc regulators. The method presented here is easy to  
calculate and yields high phase margins. For most conditions, the regulator has a phase margin between 60 and  
90 degrees. The method presented here ignores the effects of the slope compensation that is internal to the  
TPS54388C-Q1 device. As a result of ignoring the slope compensation, the actual crossover frequency is  
usually lower than the crossover frequency used in the calculations.  
To get started, calculate the modulator pole, f(p,mod), and the ESR zero, f(z,mod), using 方程式 36 and 方程式 37.  
For C(OUT), derating the capacitor is not necessary, as the 1.8-V output is a small percentage of the 10-V  
capacitor rating. If the output is a high percentage of the capacitor rating, use the manufacturer information for  
the capacitor to derate the capacitor value. Use 方程式 38 and 方程式 39 to estimate a starting point for the  
crossover frequency, f(c). For the example design, f(p,mod) is 6.03 kHz and f(z,mod) is 1210 kHz. 方程式 38 is the  
geometric mean of the modulator pole and the ESR zero, and 方程式 39 is the mean of the modulator pole and  
the switching frequency. 方程式 38 yields 85.3 kHz and 方程式 39 gives 54.9 kHz. Use the lower value of 方程式  
38 or 方程式 39 as the approximate crossover frequency. For this example, f(c) is 56 kHz. Next, calculate the  
values of the compensation components. Use a resistor in series with a capacitor to create a compensating zero.  
A capacitor in parallel with these two components forms the compensating pole (if needed).  
IO(max)  
f(p,mod)  
=
2p´ VO ´ C(OUT)  
(36)  
1
f(z,mod)  
=
2p´R(ESR) ´ C(OUT)  
(37)  
(38)  
f(c)  
=
f
(p,mod) ´ f(z,mod)  
f(SW)  
f(c)  
=
f(p,mod)  
´
2
(39)  
The compensation design takes the following steps:  
1. Set up the anticipated crossover frequency. Use 方程40 to calculate the resistor value for the  
compensation network. In this example, the anticipated crossover frequency (f(c)) is 56 kHz. The power-  
stage gain (gm(ps)) is 25 S and the error-amplifier gain (gm(ea)) is 245 μS.  
2p´ f(c) ´ VO ´ C(OUT)  
R3 =  
g
m(ea) ´ V ´ gm(ps)  
ref  
(40)  
2. Place a compensation zero at the pole formed by the load resistor and the output capacitor. Calculate the  
capacitor for the compensation network using 方程41.  
R0´ C0  
C3 =  
R3  
(41)  
3. One can include an additional pole to attenuate high-frequency noise. In this application, the extra pole is not  
necessary.  
From the procedures above, the compensation network includes a 7.68-kresistor and a 3300-pF capacitor.  
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8.2.2.9 Power-Dissipation Estimate  
The following formulas show how to estimate the IC power dissipation under continuous-conduction mode  
(CCM) operation. The power dissipation of the IC (PT) includes conduction loss (P(con)), dead-time loss (P(d)),  
switching loss (P(SW)), gate-drive loss (P(gd)) and supply-current loss (P(q)).  
2
= IO ´ rDS(on)(Temp)  
P
(con)  
(42)  
where  
IO is the output current (A)  
rDS(on)(Temp) is the on-resistance of the high-side MOSFET at a given temperature ()  
P
= f(SW)´ IO ´0.7´ 60´10-9  
(d)  
(43)  
(44)  
where  
f(SW) is the switching frequency (Hz)  
= 1/2 ´ VI ´ IO ´ f(SW) ´8´10-9  
P
(SW)  
where  
VI is the input voltage (V)  
= 2 ´ VI ´ f(SW) ´ 2´10-9  
P
(gd)  
(45)  
(46)  
P
= VI ´ 515´10-6  
(q)  
Therefore:  
PT = P(con) + P(d) + P(SW) + P(gd) + P  
(q)  
(47)  
(48)  
For a given TA, use 方程48 to calculate the junction temperature.  
TJ = TA + RqJA ´ PT  
where  
TJ is the junction temperature (°C)  
TA is the ambient temperature (°C)  
RθJA is the thermal resistance of the package (°C/W)  
PT is the total device power dissipation (W)  
For a given TJ(max) = 150°C, use 方程49 to calculate the maximum ambient temperature.  
TA(max) = TJ(max) - RqJA ´ PT  
(49)  
where  
TJ(max) is maximum junction temperature (°C)  
TA(max) is maximum ambient temperature (°C)  
Additional power losses occur in the regulator circuit because of the inductor ac and dc losses and trace  
resistance that impact the overall efficiency of the regulator.  
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8.2.3 Application Curves  
100  
90  
100  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
80  
V(VIN) = 3.3 V  
70  
V(VIN) = 5 V  
V(VIN) = 5 V  
V(VIN) = 3.3 V  
60  
50  
40  
30  
20  
10  
0
0
0.5  
1
1.5  
2
2.5  
3
0.001  
0.01  
0.1  
1
10  
Output Current (A)  
Output Current (A)  
VO = 1.8 V  
VO = 1.8 V  
8-3. Efficiency vs Load Current  
8-2. Efficiency vs Load Current  
100  
100  
2.5 V  
1.8 V  
95  
90  
85  
80  
75  
70  
65  
60  
95  
90  
85  
80  
75  
70  
65  
60  
2.5 V  
1.8 V  
1.5 V  
1.2 V  
1.05V  
3.3 V  
1.05 V  
1.2 V  
1.5 V  
55  
50  
55  
50  
0
0.5  
1
1.5  
2
2.5  
3
0
0.5  
1
1.5  
2
2.5  
3
Output Current (A)  
Output Current (A)  
V(VIN) = 3.3 V  
f(SW) = 1 MHz  
TA = 25°C  
V(VIN) = 5 V  
f(SW) = 1 MHz  
TA = 25°C  
8-4. Efficiency vs Load Current  
8-5. Efficiency vs Load Current  
V
= 2 V/div  
V
= 2 V/div  
(VIN)  
(VIN)  
EN = 1 V/div  
EN = 1 V/div  
SS/TR = 1 V/div  
SS/TR = 1 V/div  
V
= 1 V/div  
O
V
= 1 V/div  
O
Time = 5 ms/div  
Time = 500 ms/div  
8-6. Power Up VO, V(VIN)  
8-7. Power Down VO, V(VIN)  
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English Data Sheet: SLVSDQ8  
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V(VIN) = 5 V/div  
VO = 100 mV/div (ac-coupled)  
VO = 2 V/div  
EN = 2 V/div  
IO = 1 A/div (0-A to 1.5-A load step)  
PWRGD = 5 V/div  
Time = 5 ms/div  
Time = 200 µs/div  
8-8. Transient Response, 1.5-A Step  
8-9. Power Up VO, V(VIN)  
V(VIN) = 5 V/div  
VO = 20 mV/div (ac-coupled)  
VO = 2 V/div  
PH = 2 V/div  
EN = 2 V/div  
PWRGD = 5 V/div  
Time = 500 ns/div  
Time = 5 ms/div  
8-10. Power Up VO, EN  
8-11. Output Ripple, 3 A  
60  
50  
180  
150  
120  
90  
V(VIN) = 100 mV/div (ac coupled)  
40  
30  
20  
60  
10  
30  
0
0
–10  
–20  
–30  
–40  
–50  
–60  
–30  
–60  
–90  
–120  
–150  
–180  
PH = 2 V/div  
Gain  
Phase  
10  
100  
1000  
10k  
100k  
1M  
Frequency - Hz  
V(VIN) = 5 V  
IO = 3 A  
Time = 500 ns/div  
8-13. Closed-Loop Response  
8-12. Input Ripple, 3 A  
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ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
0.4  
0.3  
0.4  
0.3  
0.2  
0.1  
0.2  
V(VIN) = 5 V  
0.1  
0
0
V(VIN) = 3.3 V  
–0.1  
–0.1  
–0.2  
–0.3  
–0.4  
–0.2  
–0.3  
–0.4  
0
0.5  
1
1.5  
2
2.5  
3
3
3.5  
4
4.5  
5
5.5  
6
Output Current (A)  
Input Voltage (V)  
8-14. Load Regulation vs Load Current  
IO = 2 A  
8-15. Regulation vs Input Voltage  
9 Power Supply Recommendations  
By design, the TPS54388C-Q1 device works with an analog supply voltage range of 2.95 V to 6 V. Ensure good  
regulation for the input supply, and connect the supply to the VIN pins with the appropriate input capacitor as  
calculated in the 8.2.2.4 section. If the input supply is located more than a few inches from the TPS54388C-  
Q1 device, the design may require extra capacitance in addition to the recommended value.  
Copyright © 2023 Texas Instruments Incorporated  
English Data Sheet: SLVSDQ8  
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10 Layout  
10.1 Layout Guidelines  
Layout is a critical portion of good power-supply design. The signal paths, which conduct fast-changing currents  
or voltages, can interact with stray inductance or parasitic capacitance in several ways to generate noise or  
degrade the power-supply performance. Take care to minimize the loop area formed by the bypass-capacitor  
connections and the VIN pins. See 10-1 for a PCB layout example. Tie the GND pins and AGND pin directly  
to the thermal pad under the IC. Connect the thermal pad to any internal PCB ground planes using multiple vias  
directly under the IC. Use additional vias to connect the top-side ground area to any internal planes near the  
input and output capacitors. For operation at full-rated load, the top-side ground area, along with any additional  
internal ground planes, must provide adequate heat-dissipating area.  
Locate the input bypass capacitor as close to the IC as possible. Route the PH pin to the output inductor.  
Because the PH connection is the switching node, locate the output inductor close to the PH pins, and minimize  
the area of the PCB conductor to prevent excessive capacitive coupling. Also. locate the boot capacitor close to  
the device. Connect the sensitive analog ground connections for the feedback voltage divider, compensation  
components, slow-start capacitor, and frequency-set resistor to a separate analog ground trace as shown. The  
RT/CLK pin is particularly sensitive to noise, so locate the Rt resistor as close as possible to the IC, and connect  
it with minimal lengths of trace. Place the additional external components approximately as shown. It may be  
possible to obtain acceptable performance with alternative PCB layouts. However, this layout, meant as a  
guideline, produces good results.  
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English Data Sheet: SLVSDQ8  
 
 
TPS54388C-Q1  
ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
10.2 Layout Example  
VIA to  
Ground  
Plane  
UVLO SET  
RESISTORS  
VIN  
BOOT  
CAPACITOR  
VIN  
INPUT  
OUTPUT  
INDUCTOR  
VIN  
PH  
PH  
PH  
SS  
VOUT  
BYPASS  
CAPACITOR  
VIN  
OUTPUT  
FILTER  
EXPOSED  
POWERPAD  
AREA  
CAPACITOR  
GND  
GND  
PH  
SLOW START  
CAPACITOR  
FEEDBACK  
RESISTORS  
ANALOG  
GROUND  
TRACE  
FREQUENCY  
SET  
RESISTOR  
COMPENSATION  
NETWORK  
TOPSIDE  
GROUND  
AREA  
VIA to Ground Plane  
10-1. PCB Layout Example  
Copyright © 2023 Texas Instruments Incorporated  
English Data Sheet: SLVSDQ8  
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ZHCSL73B OCTOBER 2016 REVISED JUNE 2021  
www.ti.com.cn  
11 Device and Documentation Support  
11.1 Documentation Support  
11.1.1 Related Documentation  
For related documentation, see the following:  
Enable Functionality and Adjusting Undervoltage Lockout for TPS57112-Q1 (SLVA784)  
Interfacing TPS57xxx-Q1,TPS65320-Q1 Family, and TPS65321-Q1 Devices With Low Impendence External  
Clock Drivers (SLVA755)  
TPS57112-Q1 High Frequency (2.35 MHz) Operation (SLVA743)  
TPS54388EVM User's Guide (SLVU962)  
TPS54388-Q1 Pin Open and Short Test Results (SLVA581)  
11.2 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。  
11.3 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》。  
11.4 Trademarks  
TI E2Eis a trademark of Texas Instruments.  
所有商标均为其各自所有者的财产。  
11.5 静电放电警告  
静电放(ESD) 会损坏这个集成电路。德州仪(TI) 建议通过适当的预防措施处理所有集成电路。如果不遵守正确的处理  
和安装程序可能会损坏集成电路。  
ESD 的损坏小至导致微小的性能降级大至整个器件故障。精密的集成电路可能更容易受到损坏这是因为非常细微的参  
数更改都可能会导致器件与其发布的规格不相符。  
11.6 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 without  
revision of this document. For browser-based versions of this data sheet, see the left-hand navigation pane.  
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PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
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)  
TPS54388CQRTERQ1  
ACTIVE  
WQFN  
RTE  
16  
3000 RoHS & Green  
NIPDAU  
Level-3-260C-168 HR  
-40 to 125  
5438Q  
(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 MATERIALS INFORMATION  
www.ti.com  
2-Dec-2020  
TAPE AND REEL INFORMATION  
*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)  
TPS54388CQRTERQ1  
WQFN  
RTE  
16  
3000  
330.0  
12.4  
3.3  
3.3  
1.1  
8.0  
12.0  
Q2  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
2-Dec-2020  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
WQFN RTE 16  
SPQ  
Length (mm) Width (mm) Height (mm)  
367.0 367.0 35.0  
TPS54388CQRTERQ1  
3000  
Pack Materials-Page 2  
GENERIC PACKAGE VIEW  
RTE 16  
3 x 3, 0.5 mm pitch  
WQFN - 0.8 mm max height  
PLASTIC QUAD FLATPACK - NO LEAD  
This image is a representation of the package family, actual package may vary.  
Refer to the product data sheet for package details.  
4225944/A  
www.ti.com  
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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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Copyright © 2023,德州仪器 (TI) 公司  

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