LM53602 [TI]

2A、3.5V 至 36V 宽输入电压同步 2.1MHz 降压转换器;
LM53602
型号: LM53602
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

2A、3.5V 至 36V 宽输入电压同步 2.1MHz 降压转换器

转换器
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中文:  中文翻译
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LM53602, LM53603  
ZHCSFV3 NOVEMBER 2016  
LM53603 (3A)LM53602 (2A) 3.5V 36V VIN2.1MHz 同步降压转  
换器  
1 特性  
3 说明  
1
3A 2A 最大负载电流  
LM53603 LM53602 降压稳压器专为 12V 工业和汽  
车类 应用而设计,可通过最高 36V 的输入电压提供  
3.3V/3A 10V/2A 输出。当输入电压高达 20V 时,  
该器件可利用高级高速电路得以稳压,同时以 2.1MHz  
的开关频率提供 5V 输出。该器件采用创新型架构,在  
输入电压仅为 3.5V 时也可提供 3.3V 稳压输出。该产  
品针对工业和汽车客户进行了全方位优化。器件的输入  
电压最高可达 36V,容许的最高瞬态电压达 42V,这  
简化了输入浪涌保护设计。开漏复位输出具有滤波和延  
迟功能,可提供正确的系统状态指示。凭借这一特性,  
器件无需使用附加监控组件,这节省了成本和电路板空  
间。该器件可在 PWM 和脉频调制 (PFM) 两种模式之  
间无缝切换,并且无负载条件下的工作电流仅为  
24µA,这确保了其在所有负载条件下均可展现高效率  
和出色的瞬态响应。  
输入电压范围:3.5V 36V,瞬态电压可达 42V  
可调节输出电压范围为 3.3V 10V  
2.1MHz 固定开关频率  
±2% 输出电压容差  
结温范围:-40°C 150°C  
1.7µA 关断电流(典型值)  
无负载时的输入电源电流为 24µA(典型值)  
具有滤波和延迟功能的复位输出  
可提高效率的自动轻负载模式  
用户可选的强制脉宽调制模式 (FPWM)  
内置环路补偿、软启动、电流限制、热关断、欠压  
锁定 (UVLO) 以及外部频率同步功能  
耐热增强型 16 引脚封装:  
5mm × 4.4mm × 1mm  
器件信息(1)  
2 应用  
器件型号  
LM53603  
LM53602  
封装  
封装尺寸(标称值)  
楼宇和工厂自动化领域的工业电源  
电池供电类器件  
HTSSOP (16)  
5.00mm x 4.40mm  
低噪声和低电磁干扰 (EMI) 应用  
光纤通信系统  
(1) 要了解所有可用封装,请见数据表末尾的可订购产品附录。  
简化电路原理图  
具有 5V/3A 输出的工业电源  
1
An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,  
intellectual property matters and other important disclaimers. PRODUCTION DATA.  
English Data Sheet: SNVSAR0  
 
 
 
LM53602, LM53603  
ZHCSFV3 NOVEMBER 2016  
www.ti.com.cn  
目录  
1
2
3
4
5
6
7
特性.......................................................................... 1  
9
Application and Implementation ........................ 18  
9.1 Application Information............................................ 18  
9.2 Typical Applications ................................................ 18  
9.3 Typical Adjustable Industrial Application Circuit ..... 28  
9.4 Do's and Don't's ...................................................... 28  
应用.......................................................................... 1  
说明.......................................................................... 1  
修订历史记录 ........................................................... 2  
Device Comparison Table..................................... 3  
Pin Configuration and Functions......................... 3  
Specifications......................................................... 4  
7.1 Absolute Maximum Ratings ...................................... 4  
7.2 ESD Ratings.............................................................. 4  
7.3 Recommended Operating Conditions....................... 5  
7.4 Thermal Information.................................................. 5  
7.5 Electrical Characteristics........................................... 6  
7.6 System Characteristics ............................................. 7  
7.7 Timing Requirements................................................ 8  
7.8 Typical Characteristics.............................................. 9  
Detailed Description ............................................ 10  
8.1 Overview ................................................................ 10  
8.2 Functional Block Diagram ....................................... 10  
8.3 Feature Description................................................. 11  
8.4 Device Functional Modes........................................ 15  
10 Power Supply Recommendations ..................... 29  
11 Layout................................................................... 30  
11.1 Layout Guidelines ................................................. 30  
11.2 Layout Example .................................................... 32  
12 器件和文档支持 ..................................................... 33  
12.1 器件支持 ............................................................... 33  
12.2 文档支持................................................................ 33  
12.3 相关链接................................................................ 33  
12.4 接收文档更新通知 ................................................. 34  
12.5 社区资源................................................................ 34  
12.6 ....................................................................... 34  
12.7 静电放电警告......................................................... 34  
12.8 Glossary................................................................ 34  
13 机械、封装和可订购信息....................................... 34  
8
4 修订历史记录  
日期  
修订版本  
注释  
2016 11 月  
*
首次发布。  
2
Copyright © 2016, Texas Instruments Incorporated  
 
LM53602, LM53603  
www.ti.com.cn  
ZHCSFV3 NOVEMBER 2016  
5 Device Comparison Table  
PART NUMBER(1)  
OUTPUT VOLTAGE  
MAXIMUM OUTPUT  
CURRENT  
PACKAGE QTY  
LM53603AMPWPR  
LM53603AMPWPT  
LM53602AMPWPR  
LM53602AMPWPT  
Adjustable  
Adjustable  
Adjustable  
Adjustable  
3 A  
3 A  
2 A  
2 A  
2000  
250  
2000  
250  
(1) Some text and images in this datasheet refer to fixed 3.3-V or 5-V output devices which are only available in the automotive grade  
version of this device as the LM53603-Q1 and LM53602-Q1. Refer to the automotive datasheet for more information on those output  
voltage options.  
6 Pin Configuration and Functions  
PWP Package  
16-Lead HTSSOP  
Top View  
SW  
1
16  
PGND  
PGND  
N/C  
SW  
2
3
15  
14  
CBOOT  
4
5
VCC  
BIAS  
13  
12  
VIN  
EP  
(17)  
VIN  
SYNC  
FPWM  
RESET  
EN  
6
7
11  
10  
AGND  
8
9
FB  
Pin Functions  
PIN  
I/O(1)  
DESCRIPTION  
NO.  
1, 2  
3
NAME  
SW  
P
P
Regulator switch node. Connect to power inductor. Connect pins 1 and 2 directly together at the PCB.  
Bootstrap supply input for gate drivers. Connect a high-quality, 470-nF capacitor from this pin to SW.  
CBOOT  
Internal 3.15-V regulator output. Used as supply to internal control circuits. Do not connect to any  
external loads. Can be used as logic supply for control inputs. Connect a high-quality, 3.3-µF capacitor  
from this pin to GND.  
4
VCC  
O
Input to internal voltage regulator. Connect to output voltage point. Do not ground. Connect a high-  
quality, 0.1-µF capacitor from this pin to GND.  
5
6
7
8
9
BIAS  
SYNC  
FPWM  
RESET  
FB  
P
I
Synchronization input to regulator. Used to synchronize the regulator switching frequency to the system  
clock. When not used connect to GND; do not float.  
Mode control input to regulator. High = forced PWM (FPWM). Low = auto mode; automatic transition  
between PFM and PWM. Do not float.  
I
Open-drain reset output. Connect to suitable voltage supply through a current limiting resistor. High =  
power OK. Low = fault. RESET goes low when EN = low.  
O
I
Feedback input to regulator. Connect to output voltage sense point for fixed 5-V and 3.3-V output.  
Connect to feedback divider tap point for ADJ option. Do not float or ground.  
Analog ground for regulator and system. All electrical parameters are measured with respect to this pin.  
Connect to EP and PGND on PCB.  
10  
AGND  
EN  
G
I
11  
Enable input to the regulator. High = ON. Low = OFF. Can be connected directly to VIN. Do not float.  
Input supply to the regulator. Connect a high-quality bypass capacitor(s) from this pin to PGND.  
Connect pins 12 and 13 directly together at the PCB.  
12, 13  
14  
VIN  
P
N/C  
This pin has no connection to the device.  
(1) O = Output, I = Input, G = Ground, P = Power  
Copyright © 2016, Texas Instruments Incorporated  
3
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ZHCSFV3 NOVEMBER 2016  
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Pin Functions (continued)  
PIN  
I/O(1)  
DESCRIPTION  
NO.  
15, 16  
17  
NAME  
PGND  
EP  
Power ground to internal low-side MOSFET. Connect to AGND and system ground. Connect pins 15  
and 16 directly together at the PCB.  
G
G
Exposed die attach paddle. Connect to ground plane for adequate heat sinking and noise reduction.  
7 Specifications  
7.1 Absolute Maximum Ratings  
over the recommended operating junction temperature range of –40°C to 150°C (unless otherwise noted)(1)  
PARAMETER  
MIN  
–0.3  
–0.3  
–0.3  
–0.3  
–0.3  
–0.3  
–0.3  
–0.3  
–0.3  
–0.3  
–0.1  
–0.3  
–40  
MAX  
40  
UNIT  
V
VIN to AGND, PGND(2)  
SW to AGND, PGND(3)  
CBOOT to SW  
VIN + 0.3  
3.6  
V
V
EN to AGND, PGND(2)  
40  
V
BIAS to AGND, PGND  
16  
V
FB to AGND, PGND : fixed 5 V and 3.3 V  
FB to AGND, PGND : ADJ  
RESET to AGND, PGND  
SYNC, FPWM, to AGND, PGND  
VCC to AGND, PGND  
16  
V
5.5  
V
8
V
5.5  
V
4.2  
V
RESET pin current(4)  
AGND to PGND(5)  
1.2  
mA  
V
0.3  
Storage temperature, Tstg  
150  
°C  
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings  
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended  
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. Values given  
are D.C.  
(2) A maximum of 42 V can be sustained at this pin for a duration of 500 ms at a duty cycle of 0.01%.  
(3) Transients on this pin, not exceeding –3 V or +40 V, can be tolerated for a duration of 100 ns. For transients between 40 V and 42 V,  
see note (2)  
.
(4) Positive current flows into this pin.  
(5) A transient voltage of ±2 V can be sustained for 1 µs.  
7.2 ESD Ratings  
VALUE  
±1500  
±2500  
UNIT  
Pins 1, 2, 3, 12, 13,  
Human-body model (HBM), per ANSI/ESDA/JEDEC JS-  
001(1)  
Pins 11, 5, 8, 9, 6, 7, 4  
Electrostatic  
discharge  
V(ESD)  
V
Pins 3, 4, 5, 6, 7, 11, 12  
and 13  
±750  
±500  
Charged-device model (CDM), per JEDEC specification  
JESD22-C101(2)  
Pins 1, 2, 8, 9, 15 and 16  
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.  
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.  
4
Copyright © 2016, Texas Instruments Incorporated  
 
 
 
LM53602, LM53603  
www.ti.com.cn  
ZHCSFV3 NOVEMBER 2016  
7.3 Recommended Operating Conditions  
over the recommended operating junction temperature range of –40°C to 150°C (unless otherwise noted)  
MIN  
3.9  
0
NOM  
MAX  
UNIT  
V
Input voltage(1)  
36  
Output voltage : fixed 5 V(2)  
Output voltage : fixed 3.3 V(2)  
Output voltage adjustment range: ADJ(2)(3)  
Output current for LM53603  
Output current for LM53602  
RESET pin current  
5
V
0
3.3  
V
3.3  
0
10  
3
V
A
0
2
A
0
1
mA  
°C  
Operating junction temperature(4)  
–40  
150  
(1) See System Characteristics for details of input voltage range.  
(2) Under no conditions should the output voltage be allowed to fall below zero volts.  
(3) An extended output voltage range to 10 V is possible with changes to the typical application schematic. Also, some system  
specifications are not achieved for output voltages greater than 6 V. Consult the factory for further information.  
(4) High junction temperatures degrade operating lifetimes. Operating lifetime is de-rated for junction temperatures greater than 125°C.  
7.4 Thermal Information  
LM53603,  
LM53602  
THERMAL METRIC(1)  
UNIT  
PWP (HTSSOP)  
16 PINS  
42.5  
22.6  
16.2  
0.6  
RθJA  
Junction-to-ambient thermal resistance  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
RθJC(top)  
RθJB  
Junction-to-case (top) thermal resistance  
Junction-to-board thermal resistance  
ψJT  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
Junction-to-case (bottom) thermal resistance  
ψJB  
16.0  
1.1  
RθJC(bot)  
(1) The values given in this table are only valid for comparison with other packages and cannot be used for design purposes. These values  
were calculated in accordance with JESD 51-7, and simulated on a 4-layer JEDEC board. They do not represent the performance  
obtained in an actual application. For design information please see the Maximum Ambient Temperature section. For more information  
about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report and the Using  
New Thermal Metrics (SBVA025) application report.  
Copyright © 2016, Texas Instruments Incorporated  
5
 
 
LM53602, LM53603  
ZHCSFV3 NOVEMBER 2016  
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7.5 Electrical Characteristics  
Limits apply to the recommended operating junction temperature range of –40°C to 150°C, unless otherwise noted. Minimum  
and maximum limits are verified through test, design, or statistical correlation. Typical values represent the most likely  
parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise stated the following conditions  
apply: VIN = 13.5 V.  
PARAMETER  
TEST CONDITIONS  
MIN(1)  
TYP  
MAX(1)  
UNIT  
VIN = 3.8 V to 36 V, FPWM,  
TJ = 25°C  
–1%  
1%  
Initial reference voltage accuracy  
for 5-V and 3.3-V options  
VFB  
VIN = 3.8 V to 36 V, FPWM  
–1.25%  
0.993  
1.25%  
1.007  
VIN = 3.8 V to 36 V, FPWM,  
TJ = 25°C  
1
1
VREF  
Reference voltage for ADJ option  
V
V
VIN = 3.8 V to 36 V, FPWM,  
TJ = –40°C to 125°C  
0.99  
1.01  
Rising  
3.2  
2.9  
3.95  
3.55  
Minimum input voltage to  
operate(2)  
VIN-operate  
Falling  
Hysteresis, below  
0.34  
Operating quiescent current;  
measured at VIN pin(3)(4)  
VBIAS = 5 V,  
TJ = –40°C to 125°C  
IQ  
8
13  
µA  
µA  
EN 0.4 V, TJ = 25°C  
EN 0.4 V, TJ = 125°C  
VBIAS = 5 V, FPWM = 3.3 V  
VIN = VEN = 13.5 V  
1.7  
Shutdown quiescent current;  
measured at VIN pin  
ISD  
3.5  
78  
IB  
Current into the BIAS pin(4)  
Current into EN pin  
47  
2.3  
µA  
µA  
nA  
IEN  
IFB  
Bias current into FB pin  
ADJ option  
10  
RESET upper threshold voltage  
RESET lower threshold voltage  
Rising, % of nominal Vout  
Falling, % of nominal Vout  
105%  
92%  
107%  
94%  
110%  
96.5%  
VRESET  
RESET lower threshold voltage  
with respect to output voltage  
Falling, % actual Vout  
94.5%  
1.5%  
95.7%  
VRESET-  
Hyst  
RESET hysteresis as a percent of  
output voltage set point  
Minimum input voltage for proper  
RESET function  
50-µA pullup to RESET pin, VEN = 0 V,  
TJ = 25°C  
VMIN  
1.5  
0.4  
0.4  
0.4  
V
V
50-µA pullup to RESET pin, Vin = 1.5 V,  
EN = 0 V  
Low level RESET pin output  
voltage  
0.5-mA pullup to RESET pin, Vin = 13.5  
V, EN = 0 V  
VOL  
1-mA pullup to RESET pin, Vin = 13.5 V,  
EN = 3.3 V  
Rising  
1.7  
2
VEN  
Enable input threshold voltage  
V
V
V
Hysteresis, below  
0.45  
0.55  
Enable input threshold for full  
shutdown(5)  
EN input voltage required for complete  
shutdown of the regulator, falling.  
VEN-off  
VLOGIC  
0.8  
1.5  
VIH  
Logic input levels on FPWM and  
SYNC pins  
VIL  
0.4  
6.2  
4.4  
4.3  
2.8  
LM53603  
LM53602  
LM53603  
LM53602  
4.5  
2.4  
3
IHS  
High-side switch current limit  
Low-side switch current limit(6)  
A
A
3.6  
2.4  
ILS  
2
(1) Minimum and maximum limits are 100% production tested at 25°C. Limits over the operating temperature range are verified through  
correlation using Statistical Quality Control (SQC) methods. Limits are used to calculate Average Outgoing Quality Level (AOQL).  
(2) This is the input voltage at which the device starts to operate (rising). The device shuts down when the input voltage goes below this  
value minus the hysteresis.  
(3) This is the current used by the device, open loop. It does not represent the total input current of the system when in regulation. See  
Isupply in System Characteristics  
(4) The FB pin is set to 5.5 V for this test.  
(5) Below this voltage on the EN input, the device shuts down completely.  
(6) See the Current Limit section for an explanation of valley current limit.  
6
Copyright © 2016, Texas Instruments Incorporated  
 
LM53602, LM53603  
www.ti.com.cn  
ZHCSFV3 NOVEMBER 2016  
Electrical Characteristics (continued)  
Limits apply to the recommended operating junction temperature range of –40°C to 150°C, unless otherwise noted. Minimum  
and maximum limits are verified through test, design, or statistical correlation. Typical values represent the most likely  
parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise stated the following conditions  
apply: VIN = 13.5 V.  
PARAMETER  
TEST CONDITIONS  
FPWM = 0 V  
MIN(1)  
TYP  
–0.02  
–1.5  
135  
60  
MAX(1)  
UNIT  
A
IZC  
Zero-cross current limit  
Negative current limit  
INEG  
FPWM = 3.3 V  
A
High-side MOSFET resistance  
Low-side MOSFET resistance  
VIN = 3.8 V to 18 V  
290  
125  
Rdson  
Power switch on-resistance  
Switching frequency  
mΩ  
1.85  
1.9  
2.1  
2.35  
FSW  
MHz  
VIN = 36 V  
1.2  
FSYNC  
VCC  
Synchronizing frequency range  
Internal VCC voltage  
2.1  
2.3  
MHz  
V
VBIAS = 3.3 V  
Rising  
3.15  
162  
18  
178  
TSD  
Thermal shutdown thresholds  
°C  
Hysteresis, below  
7.6 System Characteristics  
The following specifications apply only to the typical application circuit, shown in Figure 15 with nominal component values.  
Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. The  
parameters in this table are not ensured.  
PARAMETER  
TEST CONDITIONS  
VOUT = 3.3 V, IOUT = 3 A  
MIN  
TYP  
3.9  
3.55  
7
MAX  
UNIT  
Minimum input voltage for Vout to  
stay within ±2% of regulation(1)  
VIN-MIN  
V
VOUT = 3.3 V, IOUT = 1 A  
VOUT = 5 V, VIN = 8 V to 36 V, IOUT = 3 A  
Line Regulation  
mV  
mV  
VOUT = 3.3 V, VIN = 6 V to 36 V, IOUT = 3  
A
5
77  
53  
12  
9
VOUT = 5 V, VIN = 12 V, IOUT = 10 µA to 3  
A
Load Regulation : Auto Mode  
Regulation  
VOUT = 3.3 V, VIN = 12 V, IOUT = 10 µA to  
3 A  
VOUT = 5 V, VIN = 12 V, IOUT = 10 µA to 3  
A
Load Regulation : FPWM Mode  
mV  
µA  
VOUT = 3.3 V, VIN = 12 V, IOUT = 10 µA to  
3 A  
VIN = 13.5 V, VOUT = 3.3 V, IOUT = 0 A  
VIN = 13.5 V, VOUT = 5 V, IOUT = 0 A  
24  
34  
Input supply current when in  
regulation(2)  
ISUPPLY  
5-V Option:  
VOUT = 4.95 V, IOUT = 3 A, FSW < 1.85  
MHz  
0.7  
1.8  
5-V Option:  
VOUT = 5 V, IOUT = 3 A, FSW = 1.85 MHz  
VDROP  
Dropout voltage (VIN – VOUT  
)
V
3.3-V Option:  
VOUT = 3.27 V, IOUT = 3 A, FSW < 1.85  
MHz  
0.65  
3.3-V Option:  
VOUT = 3.3 V, IOUT = 3 A, FSW = 1.85  
MHz  
1.8  
(1) This parameter is valid once the input voltage has risen above VIN-operate and the device has started up.  
(2) Includes current into the EN pin, but does not include current due to the external resistive divider in adjustable output versions. See  
Input Supply Current section.  
Copyright © 2016, Texas Instruments Incorporated  
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ZHCSFV3 NOVEMBER 2016  
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7.7 Timing Requirements  
Limits apply to the recommended operating junction temperature range of –40°C to 150°C, unless otherwise noted. Minimum  
and maximum limits are verified through test, design, or statistical correlation. Typical values represent the most likely  
parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise stated the following conditions  
apply: VIN = 13.5 V.  
MIN  
NOM  
50  
125  
3
MAX  
80  
200  
4
UNIT  
ns  
TON  
Minimum switch on-time, VIN = 20 V  
Minimum switch off-time, VIN = 3.8 V  
Delay time to RESET high signal  
Glitch filter time for RESET function  
Soft-start time  
TOFF  
ns  
TRESET-act  
TRESET-filter  
TSS  
2
12  
1
ms  
µs  
25  
2
45  
3
ms  
ms  
ms  
TEN  
Turnon delay, CVCC = 1 µF, TJ = 25°C(1)  
1
TW  
Short-circuit wait time (Hiccup time)  
5.5  
(1) This is the time from the rising edge of EN to the time that the soft-start ramp begins.  
8
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7.8 Typical Characteristics  
Unless otherwise specified the following conditions apply: VIN = 12 V, TA = 25°C. Specified temperatures are ambient.  
1.02  
1.015  
1.01  
1.005  
1
2.2  
2.15  
2.1  
2.05  
2
0.995  
0.99  
0.985  
0.98  
1.95  
1.9  
1.85  
1.8  
-60 -40 -20  
0
20  
40  
60  
80 100 120 140  
-60 -40 -20  
0
20  
40  
60  
80 100 120 140  
Temperature (°C)  
Temperature (°C)  
D001  
D002  
Figure 1. Reference Voltage for ADJ Device  
Figure 2. Switching Frequency  
7
6
5
4
3
2
1
3.5  
3.45  
3.4  
-40°C  
27°C  
125°C  
-40°C  
27°C  
125°C  
3.35  
3.3  
3.25  
3.2  
3.15  
3.1  
3.05  
3
0
0
5
10  
15  
20  
25  
30  
35  
40  
0
5
10  
15  
20  
25  
30  
35  
40  
Input Voltage (V)  
Input Voltage (V)  
D004  
D005  
Figure 3. High-Side Peak Current Limit for LM53603  
Figure 4. Low-Side Valley Current Limit for LM53603  
0.4  
0.35  
0.3  
25  
20  
15  
10  
5
-40°C  
27°C  
125°C  
-40°C  
25°C  
125°C  
0.25  
0.2  
0.15  
0.1  
0.05  
0
0
0
5
10  
15  
20  
25  
30  
35  
40  
0
5
10  
15  
20  
25  
30  
35  
40  
Input Voltage (V)  
Input Voltage (V)  
D006  
D003  
Figure 5. Short-Circuit Output Current for LM53603  
Figure 6. Shutdown Current  
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8 Detailed Description  
8.1 Overview  
The LM5360x family of devices are synchronous current mode buck regulators designed specifically for the Wide  
Input voltage Industrial and automotive market. The regulator automatically switches between PWM and PFM  
depending on load. At heavy loads the device operates in PWM at a switching frequency of 2.1 MHz. The  
regulator's oscillator can also be synchronized to an external system clock. At input voltages above about 20 V,  
the switching frequency reduces to maintain regulation during conditions of abnormally high battery voltage. At  
light loads the mode changes to PFM, with diode emulation allowing DCM. This reduces input supply current and  
keeps the efficiency high. The user can also choose to lock the mode in PWM (FPWM) so that the switching  
frequency remains constant regardless of load.  
A RESET flag is provided to indicate when the output voltage is near its regulation point. This feature includes  
filtering and a delay before asserting. This helps to prevent false flag operation during output voltage transients.  
Note that, throughout this data sheet, references to the LM53603 apply equally to the LM53602. The difference  
between the two devices is the maximum output current and specified MOSFET current limits.  
8.2 Functional Block Diagram  
SYNC  
VCC BIAS  
VIN  
* = Not used in -ADJ  
INT. REG.  
BIAS  
OSCILLATOR  
CBOOT  
ENABLE  
LOGIC  
HS CURRENT  
SENSE  
EN  
FB  
1.0 V  
Reference  
PWM  
COMP.  
ERROR  
AMPLIFIER  
+
-
CONTROL  
LOGIC  
DRIVER  
SW  
*
*
+
-
LS CURRENT  
SENSE  
RESET  
MODE  
LOGIC  
RESET  
CONTROL  
FPWM  
AGND PGND  
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8.3 Feature Description  
8.3.1 RESET Flag Output  
The RESET function, built-in to the LM53603, has special features not found in the ordinary Power Good  
function. A glitch filter prevents false flag operation for short excursions in the output voltage, such as during line  
and load transients. Furthermore, there is a delay between the point at which the output voltage is within  
specified limits and the flag asserts Power Good. Because the RESET comparator and the regulation loop share  
the same reference, the thresholds track with the output voltage. This allows the LM53603 to be specified with a  
96.5% maximum threshold, while at the same time specifying a 95% threshold with respect to the actual output  
voltage for that device. This allows tighter tolerance than is possible with an external supervisor device. The net  
result is a more accurate power-good function while expanding the system allowance for transients, and so forth.  
RESET operation can best be understood by reference to Figure 7 and Figure 8. The values for the various filter  
and delay times can be found in the Timing Requirements table. Output voltage excursions lasting less than  
TRESET-filter, do not trip RESET. Once the output voltage is within the prescribed limits, a delay of TRESET-act is  
imposed before RESET goes high.  
This output consists of an open-drain NMOS; requiring an external pullup resistor to a suitable logic supply. It  
can also be pulled up to either VCC or VOUT, through an appropriate resistor, as desired. If this function is not  
needed, the pin should be left floating or grounded. When EN is pulled low, the flag output is also forced low.  
With EN low, RESET remains valid as long as the input voltage is 1.5 V. The maximum current into this pin  
should be limited to 1 mA, while the maximum voltage should be less than 8 V.  
VOUT  
107%  
106%  
94%  
93%  
RESET  
High = Power Good  
Low = Fault  
Figure 7. Static RESET Operation  
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Feature Description (continued)  
Glitches do not cause false operation nor reset timer  
VOUT  
94%  
93%  
< Treset_filter  
RESET  
Treset_filter  
Figure 8. RESET Timing Behavior  
Treset_act  
Treset_act  
8.3.2 Enable and Start-Up  
Start-up and shutdown of the LM53603 are controlled by the EN input. Applying a voltage of 2 V activates the  
device, while a voltage of 0.8 V is required to shut it down. The EN input may also be connected directly to the  
input voltage supply, if this feature is not needed. This input must not be left floating. The LM53603 uses a  
reference based soft-start, that prevents output voltage overshoots and large inrush currents as the regulator is  
starting up. A typical start-up waveform is shown in Figure 9 along with typical timings.  
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Feature Description (continued)  
EN  
RESET  
Treset_act  
TSS  
VOUT  
TEN  
1ms/div
Figure 9. Typical Start-Up Waveform  
8.3.3 Current Limit  
The LM53603 incorporates valley current limit for normal overloads and for short-circuit protection. In addition,  
the low side switch is also protected from excessive negative current when the device is in FPWM mode. Finally,  
a high-side peak current limit is employed for protection of the top NMOS FET.  
During overloads the low-side current limit, ILS (see Electrical Characteristics), determines the maximum load  
current that the LM53603 can supply. When the low-side switch turns on, the inductor current begins to ramp  
down. If the current does not fall below ILS before the next turnon cycle, then that cycle is skipped and the low-  
side FET is left on until the current falls below ILS. This is somewhat different than the more typical peak current  
limit, and results in Equation 1 for the maximum load current.  
(
V
IN - VOUT  
2FS L  
)
VOUT  
IOUT  
= ILS  
+
max  
V
IN  
(1)  
If the above situation persists for more than about 64 clock cycles, the device turns off both high-side and low-  
side switches for approximately 5.5 ms (see TW in Timing Requirements). If the overload is still present after the  
hiccup time, another 64 cycles is counted and the process is repeated. If the current limit is not tripped for two  
consecutive clock cycles, the counter is reset. Figure 10 shows the inductor current with a hard short on the  
output. The hiccup time allows the inductor current to fall to zero, resetting the inductor volt-second balance. This  
is the method used for short-circuit protection and keeps the power dissipation low during a fault. Of course the  
output current is greatly reduced in this condition (see Typical Characteristics). A typical short-circuit transient  
and recovery is shown in Figure 11.  
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Feature Description (continued)  
Short Removed  
Short Applied  
VOUT, 2V/div  
Iinductor, 500mA/div  
Iinductor, 2A/div  
5ms/div  
2 ms/div  
Figure 11. Short-Circuit Transient and Recovery  
Figure 10. Inductor Current Bursts in Short Circuit  
The high-side current limit trips when the peak inductor current reaches IHS (see Electrical Characteristics). This  
is a cycle-by-cycle current limit and does not produce any frequency or current fold-back. It is meant to protect  
the high-side MOSFET from excessive current. Under some conditions, such as high input voltage, this current  
limit may trip before the low-side protection. The peak value of this current limit varies with duty-cycle.  
In FPWM mode, the inductor current is allowed to go negative. Should this current exceed INEG, the low-side  
switch is turned off until the next clock cycle. This is used to protect the low-side switch from excessive negative  
current. When the device is in AUTO mode, the negative current limit is increased to about 0 A; IZC. This allows  
the device to operate in DCM.  
8.3.4 Synchronizing Input  
The internal clock of the LM53603 can be synchronized to a system clock through the SYNC input. This input  
recognizes a valid high level as that 1.5 V, and a valid low as that 0.4 V. The frequency synchronization  
signal should be in the range of 1.9 MHz to 2.3 MHz with a duty cycle of from 10% to 90%. The internal clock is  
synced to the rising edge of the external clock. If this input is not used, it should be grounded. The maximum  
voltage on this input is 5.5 V; and should not be allowed to float. See the Device Functional Modes section to  
determine which modes are valid for synchronizing the clock.  
8.3.5 Input Supply Current  
The LM53603 is designed to have very low input supply current when regulating light loads. One way this is  
achieved is by powering much of the internal circuitry from the output. The BIAS pin is the input to the LDO that  
powers the majority of the control circuits. By connecting the BIAS input to the output of the regulator, this current  
acts as a small load on the output. This current is reduced by the ratio of VOUT/VIN, just like any other load.  
Another advantage of the LM53603 is that the feedback divider is integrated into the device. This allows the use  
of much larger resistors than can be used externally; >> 100 kΩ. This results in much lower divider current than  
is possible with external resistors. Equation 2 can be used to estimate the total input supply current when the  
device is regulating with no external loads. The terms of the equation are as follows:  
IIN: Input supply current with no load.  
IQ: Device quiescent current, see Electrical Characteristics.  
IEN: Current into EN pin; see Electrical Characteristics.  
IB: Current into BIAS pin; see Electrical Characteristics.  
K: 0.9  
«
÷
÷
VOUT  
VOUT  
RFB  
IIN = IQ +IEN  
+
IB +  
V K  
IN  
(2)  
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Feature Description (continued)  
Equation 2 can be used as a guide to indicate how the various terms affect the input supply current. The  
Application Curves show measured values for the input supply current for both 3.3-V and 5-V output voltage  
versions.  
8.3.6 UVLO and TSD  
The LM53603 incorporates an input undervoltage lockout (UVLO) function. The device accepts an EN command  
when the input voltage rises above about 3.64 V and shuts down when the input falls below about 3.3 V. See the  
Electrical Characteristics table under VIN-operate for detailed specifications.  
Thermal shutdown is provided to protect the device from excessive temperature. When the junction temperature  
reaches about 162°C, the device shuts down; restart occurs at a temperature of about 144ºC.  
8.4 Device Functional Modes  
See Table 1 and the following paragraphs for a detailed description of the functional modes for the LM53603.  
These modes are controlled by the FPWM input as shown in Table 1. This input can be controlled by any  
compatible logic, and the mode changed while the regulator is operating. If it is desired to lock the mode for a  
given application, the input can be either connected to ground, a logic supply, or the VCC pin, as desired. The  
maximum input voltage on this pin is 5.5 V and it should not be allowed to float.  
Table 1. Mode Selection  
FPWM INPUT VOLTAGE  
OPERATING MODE  
Forced PWM: The regulator operates as a constant frequency, current mode, full-  
> 1.5 V  
synchronous converter for all loads; without diode emulation.  
AUTO: The regulator moves between PFM and PWM as the load current changes, using  
diode-emulation-mode to allow DCM (see the Glossary).  
< 0.4 V  
8.4.1 AUTO Mode  
In AUTO mode the device moves between PWM and PFM as the load changes. At light loads the regulator  
operates in PFM. At higher loads the mode changes to PWM. The load currents for which the devices moves  
from PWM to PFM can be found in the Application Curves.  
In PWM , the converter operates as a constant frequency, current mode, full synchronous converter using PWM  
to regulate the output voltage. While operating in this mode the output voltage is regulated by switching at a  
constant frequency and modulating the duty cycle to control the power to the load. This provides excellent line  
and load regulation and low output voltage ripple. When in PWM, the converter synchronizes to any valid clock  
signal on the SYNC input (see Dropout and Input Voltage Frequency Fold-Back).  
In PFM the high-side FET is turned on in a burst of one or more cycles to provide energy to the load. The  
frequency of these bursts is adjusted to regulate the output, while diode emulation is used to maximize efficiency.  
This mode provides high light load efficiency by reducing the amount of input supply current required to regulate  
the output voltage at small loads Glossary. This trades off very good light load efficiency for larger output voltage  
ripple and variable switching frequency. Also, a small increase in the output voltage occurs in PFM. The actual  
switching frequency and output voltage ripple depend on the input voltage, output voltage, and load. Typical  
switching waveforms for PFM are shown in Figure 12. See the Application Curves for output voltage variation in  
AUTO mode. The SYNC input is ignored during PFM operation.  
A unique feature of this device, is that a minimum input voltage is required for the regulator to switch from PWM  
to PFM at light load. This feature is a consequence of the advanced architecture employed to provide high  
efficiency at light loads. Figure 13 indicates typical values of input voltage required to switch modes at no-load.  
Also, once the regulator switches to PFM, at light load, it remains in that mode if the input voltage is reduced.  
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SW, 5V/div  
VOUT, 50mV/div  
Iinductor, 500mA/div  
10µs/div  
Figure 12. Typical PFM Switching Waveforms  
8
3.3 V  
5 V  
7.5  
7
6.5  
6
5.5  
5
4.5  
4
3.5  
3
-60 -40 -20  
0
20  
40  
60  
80 100 120 140  
Temperature (°C)  
D023  
Figure 13. Input Voltage for Mode Change  
8.4.2 FPWM Mode  
With a logic high on the FPWM input, the device is locked in PWM mode. This operation is maintained, even at  
no-load, by allowing the inductor current to reverse its normal direction. This mode trades off reduced light load  
efficiency for low output voltage ripple, tight output voltage regulation, and constant switching frequency. In this  
mode, a negative current limit of INEG is imposed to prevent damage to the regulators low-side FET. When in  
FPWM, the converter synchronizes to any valid clock signal on the SYNC input (see Dropout and Input Voltage  
Frequency Fold-Back).  
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8.4.3 Dropout  
One of the parameters that influences the dropout performance of a buck regulator is the minimum off-time. As  
the input voltage is reduced, to near the output voltage, the off-time of the high-side switch starts to approach the  
minimum value (see Timing Requirements). Beyond this point the switching may become erratic or the output  
voltage falls out of regulation. To avoid this problem, the LM53603 automatically reduces the switching frequency  
to increase the effective duty cycle. This results in two specifications regarding dropout voltage, as shown in the  
System Characteristics table. One specification indicates when the switching frequency drops to 1.85 MHz;  
avoiding the A.M. radio band. The other specification indicates when the output voltage has fallen to 1% of  
nominal. See the Application Curves for typical values of dropout. The overall dropout characteristic for the 5-V  
option, can be seen in Figure 14. The SYNC input is ignored during frequency fold-back in dropout.  
5.2  
5
4.8  
4.6  
4.4  
1A  
4.2  
2A  
3A  
4
4
4.5  
5
5.5  
6
6.5  
7
Input Voltage (V)  
C003  
Figure 14. Overall Dropout Characteristic  
VOUT = 5V  
8.4.4 Input Voltage Frequency Fold-Back  
At higher input voltages the on-time of the high-side switch becomes small. When the minimum is reached (see  
Timing Requirements), the switching may become erratic or the output voltage falls out of regulation. To avoid  
this behavior, the LM53603 automatically reduces the switching frequency at input voltages above about 20 V  
(see Application Curves). In this way the device avoids the minimum on-time restriction and maintains regulation  
at abnormally high battery voltages. The SYNC input is ignored during frequency fold-back at high input voltages.  
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9 Application and Implementation  
NOTE  
Information in the following applications sections is not part of the TI component  
specification, and TI does not warrant its accuracy or completeness. TI's customers are  
responsible for determining the suitability of components for their purposes. Customers  
should validate and test their design implementation to confirm system functionality.  
9.1 Application Information  
The LM53603 and LM53602 are step-down DC-DC converters, typically used to convert a higher DC voltage to a  
lower DC voltage with a maximum output current of either 3 A or 2 A. The following design procedure can be  
used to select components for the LM53603 or LM53602. Alternately, the WEBENCH® Design Tool may be used  
to generate a complete design. This tool uses an iterative design procedure and has access to a comprehensive  
database of components. This allows the tool to create an optimized design and allows the user to experiment  
with various design options.  
9.2 Typical Applications  
9.2.1 Typical and Full-Featured Industrial Application Circuits  
Figure 15 shows the minimum required application circuit for the fixed output voltage versions, while Figure 16  
shows the connections for complete processor control of the LM53603. See these figures while following the  
design procedures. Table 2 provides an example of typical design requirements.  
L
VOUT  
VIN  
SW  
LM53603  
VIN  
6V to 36V  
CIN  
10nF  
2.2 µH  
5V or 3.3V  
3A  
EN  
CBOOT  
3x 10µF  
RESET  
VCC  
CBOOT  
FB  
COUT  
0.47 µF  
3x 22µF  
SYNC  
FPWM  
AGND  
PGND  
CVCC  
3.3 µF  
RBIAS  
3  
BIAS  
CBIAS  
0.1 µF  
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Figure 15. Typical Industrial Power Supply Schematic  
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Typical Applications (continued)  
VIN  
6V to 36V  
CIN  
10nF  
3x 10µF  
L
VOUT  
SW  
CBOOT  
FB  
LM53603  
VIN  
EN  
2.2 µH  
3.3V or 5V  
3A  
CBOOT  
FPWM  
SYNC  
RESET  
VCC  
COUT  
µC  
0.47 µF  
3x 22µF  
100 k  
CVCC  
3.3 µF  
AGND  
PGND  
RBIAS  
3 Ω  
BIAS  
CBIAS  
0.1 µF  
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Figure 16. Full-Featured Industrial Power Supply Schematic  
9.2.1.1 Design Parameters  
There are a few design parameters to take into account. Most of those choices decide which version of the  
device to use. The desired output current steers the designer toward a LM53602 type or LM53603 type part. If  
the output voltage is 3.3 V or 5 V, a fixed output version of the device can be used. Any other voltage level within  
the tolerance of the part can be achieved by using an adjustable version of the device. Most but not all  
parameters are independent of the of the IC choice. The output filter components (inductor and output  
capacitors) might vary with the choice of output voltage, especially for output voltages higher than 5 V. See  
Detailed Design Procedure for help in choosing these components.  
Table 2. Design Parameters  
DESIGN PARAMETER  
Input voltage  
EXAMPLE VALUE  
12 V  
5 V  
Output voltage  
Maximum output current  
3 A  
9.2.1.2 Detailed Design Procedure  
The following detailed design procedure applies to Figure 15, Figure 16, and Figure 45.  
9.2.1.2.1 Setting the Output Voltage  
For the fixed output voltage versions, the FB input is connected directly to the output voltage node. Preferably,  
near the top of the output capacitor. If the feed-back point is located further away from the output capacitors (that  
is, remote sensing), then a small 100-nF capacitor may be needed at the sensing point.  
For output voltages other than 5 V or 3.3 V, a feedback divider is required. For the ADJ version of the device, the  
regulator holds the FB pin at 1 V. The range of adjustable output voltage can be found in the Recommended  
Operating Conditions. Equation 3 can be used to determine RFBB for a desired output voltage and a given RFBT  
.
Usually RFBT is limited to a maximum value of 100 kΩ.  
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»
ÿ
Ÿ
1V  
RFBB = RFBT  
VOUT -1V  
(3)  
In addition, a feed-forward capacitor CFF may be required to optimize the transient response. For output voltages  
greater than 6 V, the WEBENCH Design Tool can be used to optimize the design. Recommended CFF values for  
some cases are given in the table below. It is important to note that these values provide a first approximation  
only and need to be verified for each application by the designer.  
Table 3. Recommended CFFcapacitors  
VOUT  
3.2V  
3.2V  
5.1V  
5.1V  
8V  
COUT (nominal)(1)  
44µF  
L
RFBT  
RFBB  
CFF  
2.2µH  
2.2µH  
2.2µH  
2.2µH  
4.7µH  
4.7µH  
4.7µH  
69.8kΩ  
69.8kΩ  
80.6kΩ  
80.6kΩ  
86.6kΩ  
86.6kΩ  
90.9kΩ  
31.6kΩ  
31.6kΩ  
19.6kΩ  
19.6kΩ  
12.4kΩ  
12.4kΩ  
10.0kΩ  
33pF  
110µF  
120pF  
33pF  
44µF  
110µF  
220pF  
120pF  
220pF  
120pF  
66µF  
8V  
100µF  
10V  
66µF  
(1) 16V X7R capacitors used : C3225X7R1C226M250AC (TDK)  
9.2.1.2.2 Output Capacitors  
The LM53603 is designed to work with low-ESR ceramic capacitors. The effective value of these capacitors is  
defined as the actual capacitance under voltage bias and temperature. All ceramic capacitors have a large  
voltage coefficient, in addition to normal tolerances and temperature coefficients. Under DC bias, the capacitance  
value drops considerably. Larger case sizes or higher voltage capacitors are better in this regard. To help  
mitigate these effects, multiple small capacitors can be used in parallel to bring the minimum effective  
capacitance up to the desired value. This can also ease the RMS current requirements on a single capacitor.  
Table 4 shows the nominal and minimum values of total output capacitance recommended for the LM53603. The  
values shown also provide a starting point for other output voltages, when using the ADJ option. Also shown are  
the measured values of effective capacitance for the indicated capacitor. More output capacitance can be used  
to improve transient performance and reduce output voltage ripple.  
In practice, the output capacitor has the most influence on the transient response and loop phase margin. Load  
transient testing and Bode plots are the best way to validate any given design, and should always be completed  
before the application goes into production. A careful study of temperature and bias voltage variation of any  
candidate ceramic capacitor should be made to ensure that the minimum value of effective capacitance is  
provided. The best way to obtain an optimum design is to use the Texas Instruments WEBENCH Design Tool.  
In ADJ applications the feed-forward capacitor, CFF, provides another degree of freedom when stabilizing and  
optimizing the design. Application report Optimizing Transient Response of Internally Compensated dc-dc  
Converters With Feedforward Capacitor (SLVA289) should prove helpful when adjusting the feed-forward  
capacitor.  
In addition to the capacitance shown in Table 4, a small ceramic capacitor placed on the output can help to  
reduce high frequency noise. Small case size ceramic capacitors in the range of 1 nF to 100 nF can be very  
helpful in reducing spikes on the output caused by inductor parasitics.  
The maximum value of total output capacitance should be limited to between 300 µF and 400 µF. Large values  
of output capacitance can prevent the regulator from starting-up correctly and adversely effect the loop stability. If  
values in the range given above, or greater, are to be used, then a careful study of start-up at full load and loop  
stability must be performed.  
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Table 4. Recommended Output Capacitors  
OUTPUT  
VOLTAGE  
PART NUMBER  
(MANUFACTURER)  
NOMINAL OUTPUT CAPACITANCE  
MINIMUM OUTPUT CAPACITANCE  
RATED  
CAPACITANCE  
MEASURED  
RATED  
MEASURED  
CAPACITANCE(1) CAPACITANCE  
CAPACITANCE(1)  
3.3 V  
5 V  
3 × 22 µF  
3 × 22 µF  
3 × 22 µF  
3 × 22 µF  
63 µF  
60 µF  
59 µF  
48 µF  
2 × 22 µF  
2 × 22 µF  
2 × 22 µF  
2 × 22 µF  
42 µF  
40 µF  
39 µF  
32 µF  
C3225X7R1C226M250AC (TDK)  
C3225X7R1C226M250AC (TDK)  
C3225X7R1C226M250AC (TDK)  
C3225X7R1C226M250AC (TDK)  
6 V  
10 V(2)  
(1) Measured at indicated VOUT at 25°C.  
(2) The following components were used: CFF = 47 pF, RFBT = 100 kΩ, RFBB = 11 kΩ, L = 4. 7 µH.  
9.2.1.2.3 Input Capacitors  
The ceramic input capacitors provide a low impedance source to the regulator in addition to supplying ripple  
current and isolating switching noise from other circuits. Table 5 shows the nominal and minimum values of total  
input capacitance recommenced for the LM53603. Also shown are the measured values of effective capacitance  
for the indicated capacitor. In addition, small high frequency bypass capacitors connected directly between the  
VIN and PGND pins are very helpful in reducing noise spikes and aid in reducing conducted EMI. TI  
recommends that a small case size 10-nF ceramic capacitor be placed across the input, as close as possible to  
the device (see Figure 47). Additional high frequency capacitors can be used to help manage conducted EMI or  
voltage spike issues that may be encountered.  
Table 5. Recommended Input Capacitors  
NOMINAL INPUT CAPACITANCE  
MINIMUM INPUT CAPACITANCE  
PART NUMBER (MANUFACTURER)  
RATED  
CAPACITANCE  
MEASURED  
CAPACITANCE  
RATED  
CAPACITANCE  
MEASURED  
(1)  
CAPACITANCE(1)  
3 x 10 µF  
22.5 µF  
2 × 10 µF  
15 µF  
CL32B106KBJNNNE (Samsung)  
(1) Measured at 14 V and 25°C.  
Many times it is desirable to use an electrolytic capacitor on the input, in parallel with the ceramics. This is  
especially true if longs leads or traces are used to connect the input supply to the regulator. The moderate ESR  
of this capacitor can help damp any ringing on the input supply caused by long power leads. The use of this  
additional capacitor also helps with voltage dips caused by input supplies with unusually high impedance.  
Most of the input switching current passes through the ceramic input capacitor(s). The approximate RMS value of  
this current can be calculated from Equation 4 and should be checked against the manufacturers' maximum  
ratings.  
IOUT  
IRMS  
@
2
(4)  
9.2.1.2.4 Inductor  
The LM53603 and LM53602 are optimized for a nominal inductance of 2.2 µH for the 5-V and 3.3-V versions.  
This gives a ripple current that is approximately 20% to 30% of the full load current of 3 A. For output voltages  
greater than 5 V, a proportionally larger inductor can be used. This keeps the ratio of inductor current slope to  
internal compensating slope constant.  
The most important inductor parameters are saturation current and parasitic resistance. Inductors with a  
saturation current of between 5 A and 6 A are appropriate for most applications, when using the LM53603. For  
the LM53602, inductors with a saturation current of between 4 A and 5 A are appropriate. Of course the inductor  
parasitic resistance should be as low as possible to reduce losses at heavy loads. Table 6 gives a list of several  
possible inductors that can be used with the LM53603.  
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Table 6. Recommenced Inductors  
SATURATION  
CURRENT  
MANUFACTURER  
PART NUMBER  
DC RESISTANCE  
Würth  
Coilcraft  
Coiltronics  
Vishay  
7440650022  
6 A  
15 mΩ  
11 mΩ  
48 mΩ  
18 mΩ  
28 mΩ  
13 mΩ  
DO3316T-222MLB  
MPI4040R3-2R2-R  
IHLP2525CZER2R2M01  
IHLP2525BDER2R2M01  
XAL6030-222ME  
7.8 A  
7.9 A  
14 A  
Vishay  
14 A  
Coilcraft  
16 A  
9.2.1.2.5 VCC  
The VCC pin is the output of the internal LDO, used to supply the control circuits of the LM53603. This output  
requires a 3.3-µF to 4.7-µF, ceramic capacitor connected from VCC to GND for proper operation. An X7R device  
with a rating of 10 V is highly recommended. In general this output should not be loaded with any external  
circuitry. However, it can be used to supply a logic level to the FPWM input, or for the pullup resistor used with  
the RESET output (see Figure 16). The nominal output of the LDO is 3.15 V.  
9.2.1.2.6 BIAS  
The BIAS pin is the input to the internal LDO. As mentioned in Input Supply Current, this input is connected to  
VOUT to provide the lowest possible supply current at light loads. Because this input is connected directly to the  
output, it should be protected from negative voltage transients. Such transients may occur when the output is  
shorted at the end of a long PCB trace or cable. If this is likely, in a given application, then a small resistor  
should be placed in series between the BIAS input and VOUT, as shown in Figure 15. The resistor should be  
sized to limit the current out of the BIAS pin to <100 mA. Values in the range of 2 Ω to 5 Ω are usually sufficient.  
Values greater than 5 Ω are not recommended. As a rough estimate, assume that the full negative transient  
appears across RBIAS and design for a current of < 100 mA. In severe cases, a Schottky diode can be placed in  
parallel with the output to limit the transient voltage and current.  
9.2.1.2.7 CBOOT  
The LM53603 requires a boot-strap capacitor between the CBOOT pin and the SW pin. This capacitor stores  
energy that is used to supply the gate drivers for the power MOSFETs. A ceramic capacitor of 0.47 µF, 6.3 V is  
required. A 10-V rated capacitor or higher is highly recommended.  
9.2.1.2.8 Maximum Ambient Temperature  
As with any power conversion device, the LM53603 dissipates internal power while operating. The effect of this  
power dissipation is to raise the internal temperature of the converter, above ambient. The internal die  
temperature (TJ) is a function of the ambient temperature, the power loss and the effective thermal resistance,  
RθJA of the device and PCB combination. The maximum internal die temperature for the LM53603 is 150°C, thus  
establishing a limit on the maximum device power dissipation and therefore load current at high ambient  
temperatures. Equation 5 shows the relationships between the important parameters.  
(
TJ - TA  
RqJA  
)
h
1- h  
1
IOUT  
=
(
)
VOUT  
(5)  
It is easy to see that larger ambient temperatures (TA) and larger values of RθJA reduce the maximum available  
output current. As stated in Semiconductor and IC Package Thermal Metrics, the values given in the Thermal  
Information table are not valid for design purposes and must not be used to estimate the thermal performance of  
the application. The values reported in that table were measured under a specific set of conditions that are never  
obtained in an actual application. The effective RθJA is a critical parameter and depends on many factors such as  
power dissipation, air temperature, PCB area, copper heat sink area, number of thermal vias under the package,  
air flow, and adjacent component placement. The LM53603 uses an advanced package with a heat spreading  
pad (EP) on the bottom. This must be soldered directly to the PCB copper ground plane to provide an effective  
heat sink, as well as a proper electrical connection. The resources in Ground and Thermal Plane Considerations  
can be used as a guide to optimal thermal PCB design and estimating RθJA for a given application environment.  
A typical example of RθJA versus copper board area is shown in Figure 17. The copper area in this graph is that  
22  
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for each layer of a four-layer board; the inner layers are 1 oz. (35 µm), while the outer layers are 2 oz. (70 µm). A  
typical curve of maximum load current versus ambient temperature, for both the LM53603 and LM53602, is  
shown in Figure 18. This data was taken with the device soldered to a PCB with an RθJA of about 17°C/W and an  
input voltage of 12 V. It must be remembered that the data shown in these graphs are for illustration only and the  
actual performance in any given application depends on all of the factors mentioned above.  
50  
3.5  
LM53603,  
3.3V  
0.5 W  
1 W  
45  
40  
35  
30  
25  
20  
LM53603,  
5V  
2 W  
3.0  
2.5  
2.0  
1.5  
1.0  
0.5  
0.0  
LM53602,  
3.3V  
LM53602,  
5V  
0
500  
1000  
1500  
2000  
2500  
3000  
Board Area (mm2)  
D024  
80  
90  
100  
110  
120  
130  
140  
150  
Ambient Temperature (C)  
C006  
Figure 17. RθJA vs Copper Board Area  
Figure 18. Maximum Output Current vs Ambient  
Temperature  
RθJA = 17°C/W, VIN = 12 V  
3
3
2.5  
2
7 Vin  
12 Vin  
18 Vin  
7 Vin  
12 Vin  
18 Vin  
2.5  
2
1.5  
1
1.5  
1
0.5  
0.5  
0
0
0.5  
1
1.5  
2
2.5  
3
0.5  
1
1.5  
2
2.5  
3
Output Current (A)  
Output Current (A)  
D032  
D033  
Figure 19. IC Power Dissipation vs Output Current for 3.3-  
V output  
Figure 20. IC Power Dissipation vs Output Current for 5-V  
output  
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9.2.1.3 Application Curves  
The following characteristics apply only to the circuit of Figure 15. These parameters are not tested and  
represent typical performance only. Unless otherwise stated, the following conditions apply: VIN = 12 V, TA  
=
25°C.  
100%  
90%  
80%  
70%  
60%  
50%  
40%  
30%  
20%  
10%  
0
5.08  
5.07  
5.06  
5.05  
5.04  
5.03  
5.02  
5.01  
5
12 VIN  
18 VIN  
7 VIN  
7 V  
12 V  
18 V  
36 V  
4.99  
4.98  
4.97  
0.00001  
0.0001  
0.001  
0.01  
0.1  
1
3
0
0.5  
1
1.5  
2
2.5  
3
3.5  
Output Current (A)  
Output Current (A)  
D028  
D008  
VOUT = 5 V  
Inductor = XAL6030-222ME  
AUTO  
VOUT = 5 V  
AUTO  
Figure 21. Efficiency  
Figure 22. Load and Line Regulation  
60  
50  
40  
30  
20  
10  
0
0.35  
0.3  
-40°C  
25°C  
105°C  
UP  
DN  
0.25  
0.2  
0.15  
0.1  
0.05  
0
0
5
10  
15  
20  
25  
30  
35  
40  
0
2
4
6
8
10  
12  
14  
16  
18  
20  
Input Voltage (V)  
Input Voltage (V)  
D014  
D013  
VOUT = 5 V  
AUTO  
IOUT = 0 A  
VOUT = 5 V  
Figure 23. Input Supply Current  
Figure 24. Load Current for Mode Change  
1
0.9  
0.8  
0.7  
0.6  
0.5  
0.4  
0.3  
0.2  
0.1  
0
3
2.5  
2
-40°C  
27°C  
105°C  
-40°C  
27°C  
105°C  
1.5  
1
0.5  
0
0
0.5  
1
1.5  
2
2.5  
3
3.5  
0
0.5  
1
1.5  
2
2.5  
3
3.5  
Output Current (A)  
Output Current (A)  
D011  
D012  
VOUT = 5 V  
Figure 25. Dropout for –1% Regulation  
VOUT = 5 V  
Figure 26. Dropout for 1.85 MHz  
24  
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LM53602, LM53603  
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The following characteristics apply only to the circuit of Figure 15. These parameters are not tested and  
represent typical performance only. Unless otherwise stated, the following conditions apply: VIN = 12 V, TA  
=
25°C.  
10000000  
1000000  
100000  
10000  
1000  
2500000  
2000000  
1500000  
1000000  
500000  
0
6 V  
0 A  
2 A  
3 A  
12 V  
18 V  
36 V  
100  
10  
1
1E-6  
1E-5 0.0001 0.001  
0.01  
0.1  
1
10  
0
5
10  
15  
20  
25  
30  
35  
40  
Output Current (A)  
Input Voltage (V)  
D031  
D026  
VOUT = 5 V  
AUTO  
VOUT = 5 V  
FPWM  
Figure 27. Switching Frequency vs Load Current  
Figure 28. Switching Frequency vs Input Voltage  
EN, 3V/div  
VOUT, 2V/div  
VOUT, 100mV/div  
RESET, 4V/div  
Iinductor, 1A/div  
Output Current, 1A/div  
50µs/div  
1ms/div  
VOUT = 5 V  
IOUT = 0 A to 3 A, TR = TF = 1 µs  
AUTO  
VOUT = 5 V  
IOUT = 0 A  
Figure 29. Start-Up  
AUTO  
Figure 30. Load Transients  
FPWM, 4v/div  
VOUT, 100mV/div  
VOUT, 100mV/div  
Iinductor, 1A/div  
Output Current, 1A/div  
2ms/div  
50µs/div  
VOUT = 5 V  
IOUT = 1 mA  
VOUT = 5 V  
IOUT = 0 A to 3 A, TR = TF = 1 µs  
FPWM  
Figure 32. Mode Change Transient  
Figure 31. Load Transient  
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The following characteristics apply only to the circuit of Figure 15. These parameters are not tested and  
represent typical performance only. Unless otherwise stated, the following conditions apply: VIN = 12 V, TA  
=
25°C.  
100%  
90%  
80%  
70%  
60%  
50%  
40%  
30%  
20%  
10%  
0
3.36  
3.35  
3.34  
3.33  
3.32  
3.31  
3.3  
12 VIN  
18 VIN  
7 VIN  
6 V  
12 V  
18 V  
36 V  
3.29  
3.28  
3.27  
0.00001  
0.0001  
0.001  
0.01  
0.1  
1
3
0
0.5  
1
1.5  
2
2.5  
3
3.5  
Output Current (A)  
Output Current (A)  
D029  
D016  
VOUT = 3.3 V  
Inductor = XAL6030-222ME  
AUTO  
VOUT = 3.3 V  
AUTO  
Figure 33. Efficiency  
Figure 34. Load and Line Regulation  
0.45  
0.4  
45  
40  
35  
30  
25  
20  
15  
10  
5
UP  
DN  
0.35  
0.3  
0.25  
0.2  
0.15  
0.1  
-40°C  
25°C  
105°C  
0.05  
0
0
0
5
10  
15  
20  
25  
30  
35  
40  
0
2
4
6
8
10  
12  
14  
16  
18  
20  
Input Voltage (V)  
Input Voltage (V)  
D022  
D021  
VOUT = 3.3 V  
AUTO  
IOUT = 0 A  
VOUT = 3.3 V  
Figure 35. Input Supply Current  
Figure 36. Load Current for Mode Change  
1
0.9  
0.8  
0.7  
0.6  
0.5  
0.4  
0.3  
0.2  
0.1  
0
2.5  
2
-40°C  
27°C  
105°C  
-40°C  
27°C  
105°C  
1.5  
1
0.5  
0
0
0.5  
1
1.5  
2
2.5  
3
3.5  
0
0.5  
1
1.5  
2
2.5  
3
3.5  
Output Current (A)  
Output Current (A)  
D019  
D020  
VOUT = 3.3 V  
Figure 37. Dropout for –1% Regulation  
VOUT = 3.3 V  
Figure 38. Dropout for 1.85 MHz  
26  
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The following characteristics apply only to the circuit of Figure 15. These parameters are not tested and  
represent typical performance only. Unless otherwise stated, the following conditions apply: VIN = 12 V, TA  
=
25°C.  
10000000  
1000000  
100000  
10000  
1000  
2500000  
2000000  
1500000  
1000000  
500000  
0
6 V  
0 A  
2 A  
3 A  
12 V  
18 V  
36 V  
100  
10  
1
1E-6  
1E-5 0.0001 0.001  
0.01  
0.1  
1
10  
0
5
10  
15  
20  
25  
30  
35  
40  
Output Current (A)  
Input Voltage (V)  
D030  
D027  
VOUT = 3.3 V  
AUTO  
VOUT = 3.3 V  
FPWM  
Figure 39. Switching Frequency vs Load Current  
Figure 40. Switching Frequency vs Input Voltage  
EN, 3V/div  
VOUT, 100mV/div  
VOUT, 2V/div  
RESET, 4V/div  
Iinductor, 1A/div  
Output Current, 1A/div  
1ms/div  
50µs/div  
VOUT = 3.3 V  
AUTO  
Figure 41. Start-Up  
IOUT = 0 A  
VOUT = 3.3 V  
IOUT = 0 A to 3 A, TR = TF = 1 µs  
AUTO  
Figure 42. Load Transient  
FPWM, 4v/div  
VOUT, 100mV/div  
VOUT, 100mV/div  
Iinductor, 1A/div  
Output Current, 1A/div  
50µs/div  
2ms/div  
VOUT = 3.3 V  
IOUT = 0 A to 3 A, TR = TF = 1 µs  
FPWM  
VOUT = 3.3 V  
IOUT = 1 mA  
Figure 43. Load Transient  
Figure 44. Mode Change Transient  
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9.3 Typical Adjustable Industrial Application Circuit  
Figure 45 shows a typical example of a design with an output voltage of 10 V; while Table 7 gives typical design  
parameters. See Detailed Design Procedure for the design procedure.  
L
10nF  
SW  
LM53603  
VOUT  
VIN  
EN  
VIN  
4.7 µH  
12V to 36V  
10V @ 3A  
CIN  
3x 10µF  
CBOOT  
RESET  
VCC  
CBOOT  
RFBT  
100 k  
COUT  
0.47 µF  
3x 22µF  
CFF  
SYNC  
FPWM  
AGND  
PGND  
47 pF  
FB  
CVCC  
3.3 µF  
RFBB  
11 kΩ  
BIAS  
RBIAS  
3  
CBIAS  
0.1 µF  
Copyright © 2016, Texas Instruments Incorporated  
Figure 45. Typical Adjustable Output Industrial Power Supply Schematic  
CD/DVD/Blu-ray Disc™ Motor Drive Applications  
VOUT = 10 V  
9.3.1 Design Parameters for Typical Adjustable Output Industrial Power Supply  
There are a few design parameters to take into account. Most of those choices decide which version of the  
device to use. The desired output current steers the designer toward a LM53602 type or LM53603 type part.  
Most but not all parameters are independent of the of the IC choice. The output filter components (inductor and  
output capacitors) might vary with the choice of output voltage, especially for output voltages higher than 5 V.  
Refer to Detailed Design Procedure for details on choosing the components for the application.  
Table 7. Design Parameters  
DESIGN PARAMETER  
Input Voltage  
EXAMPLE VALUE  
12 V  
10 V  
3 A  
Output Voltage  
Maximum Output Current  
9.4 Do's and Don't's  
Don't: Exceed the Absolute Maximum Ratings.  
Don't: Exceed the ESD Ratings.  
Don't: Exceed the Recommended Operating Conditions.  
Don't: Allow the EN, FPWM or SYNC input to float.  
Don't: Allow the output voltage to exceed the input voltage, nor go below ground.  
Don't: Use the thermal data given in the Thermal Information table to design your application.  
Do: Follow all of the guidelines and suggestions found in this data sheet, before committing your design to  
production. TI Application Engineers are ready to help critique your design and PCB layout to help make your  
project a success.  
Do: Refer to the helpful documents found in Layout Guidelines and Ground and Thermal Plane  
Considerations.  
28  
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10 Power Supply Recommendations  
The characteristics of the input supply must be compatible with the Absolute Maximum Ratings and  
Recommended Operating Conditions found in this data sheet. In addition, the input supply must be capable of  
delivering the required input current to the loaded regulator. The average input current can be estimated with  
Equation 6, where η is the efficiency.  
VOUT IOUT  
IIN =  
V ∂ h  
IN  
(6)  
If the regulator is connected to the input supply through long wires or PCB traces, take special care to achieve  
good performance. The parasitic inductance and resistance of the input cables can have an adverse effect on  
the operation of the regulator. The parasitic inductance, in combination with the low-ESR ceramic input  
capacitors, can form an under-damped resonant circuit. This circuit may cause overvoltage transients at the VIN  
pin, each time the input supply is cycled on and off. The parasitic resistance causes the voltage at the VIN pin to  
dip when the load on the regulator is switched on, or exhibits a transient. If the regulator is operating close to the  
minimum input voltage, this dip may cause the device to shutdown or reset. The best way to solve these kinds of  
issues is to reduce the distance from the input supply to the regulator or use an aluminum or tantalum input  
capacitor in parallel with the ceramics. The moderate ESR of these types of capacitors helps to damp the input  
resonant circuit and reduce any voltage overshoots. A value in the range of 20 µF to 100 µF is usually sufficient  
to provide input damping and help to hold the input voltage steady during large load transients.  
Sometimes, for other system considerations, an input filter is used in front of the regulator. This can lead to  
instability, as well as some of the effects mentioned above, unless it is designed carefully. The user guide Simple  
Success with Conducted EMI for DC-DC Converters (SNVA489), provides helpful suggestions when designing  
an input filter for any switching regulator  
In some cases a Transient Voltage Suppressor (TVS) is used on the input of regulators. One class of this device  
has a snap-back V-I characteristic (thyristor type). The use of a device with this type of characteristic is not  
recommend. When the TVS fires, the clamping voltage drops to a very low value. If this holding voltage is less  
than the output voltage of the regulator, the output capacitors is discharged through the regulator back to the  
input. This uncontrolled current flow could damage the regulator.  
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11 Layout  
11.1 Layout Guidelines  
The PCB layout of any DC-DC converter is critical to the optimal performance of the design. Bad PCB layout can  
disrupt the operation of an otherwise good schematic design. Even if the converter regulates correctly, bad PCB  
layout can mean the difference between a robust design and one that cannot be mass produced. Furthermore,  
the EMI performance of the regulator is dependent on the PCB layout, to a great extent. In a buck converter, the  
most critical PCB feature is the loop formed by the input capacitor and power ground, as shown in Figure 46.  
This loop carries fast transient currents that can cause large transient voltages when reacting with the trace  
inductance. These unwanted transient voltages disrupt the proper operation of the converter. Because of this, the  
traces in this loop should be wide and short, and the loop area as small as possible to reduce the parasitic  
inductance. Figure 47 shows a recommended layout for the critical components of the LM53603. This PCB  
layout is a good guide for any specific application. The following important guidelines must also be followed:  
1. Place the input capacitor(s) CIN as close as possible to the VIN and PGND terminals. VIN and GND  
are on the same side of the device, simplifying the input capacitor placement.  
2. Place bypass capacitors for VCC and BIAS close to their respective pins. These components must be  
placed close to the device and routed with short and wide traces to the pins and ground. The trace from  
BIAS to VOUT should be 10 mils wide. BIAS and VCC capacitors must be place within 4 mm of the BIAS  
and VCC pin (160 mils) .  
3. Use wide traces for the CBOOT capacitor. CBOOT must be placed close to the device with short and wide  
traces to the CBOOT and SW pins.  
4. Place the feedback divider as close as possible to the FB pin on the device. If a feedback divider and  
CFF are used, they must be close to the device while the length of the trace from VOUT to the divider can be  
somewhat longer. However, this latter trace must not be routed near any noise sources that can capacitively  
couple to the FB input.  
5. Use at least one ground plane in one of the middle layers. This plane acts as a noise shield and also act  
as a heat dissipation path.  
6. Connect the EP pad to the GND plane. This pad acts as a heat sink connection and a ground connection  
for the regulator. It must be solidly connected to a ground plane. The integrity of this connection has a direct  
bearing on the effective RθJA  
.
7. Provide wide paths for VIN, VOUT and GND. Making these paths as wide as possible reduces any voltage  
drops on the input or output paths of the converter and maximizes efficiency.  
8. Provide enough PCB area for proper heat sinking. As stated in the Maximum Ambient Temperature  
section, enough copper area must be used to ensures a low RθJA, commensurate with the maximum load  
current and ambient temperature. The top and bottom PCB layers must be made with two ounce copper; and  
no less than one ounce. Use an array of heat sinking vias to connect the exposed pad (EP) to the ground  
plane on the bottom PCB layer. If the PCB has multiple copper layers (recommended), these thermal vias  
can also be connected to the inner layer heat-spreading ground planes.  
9. Keep switch area small. The copper area connecting the SW pin to the inductor must be kept as short and  
wide as possible. At the same time the total area of this node must be minimized to help mitigate radiated  
EMI.  
10. These resources provide additional important guidelines:  
AN-1149 Layout Guidelines for Switching Power Supplies (SNVA021)  
AN-1229 Simple Switcher PCB Layout Guidelines (SNVA054)  
Constructing Your Power Supply- Layout Considerations (SLUP230)  
Low Radiated EMI Layout Made SIMPLE with LM4360x and LM4600x (SNVA721)  
30  
Copyright © 2016, Texas Instruments Incorporated  
 
LM53602, LM53603  
www.ti.com.cn  
ZHCSFV3 NOVEMBER 2016  
Layout Guidelines (continued)  
VIN  
CIN  
SW  
GND  
Figure 46. Current Loops With Fast Transients  
11.1.1 Ground and Thermal Plane Considerations  
As mentioned in the Layout Guidelines, TI recommends using one of the middle layers as a solid ground plane.  
A ground plane provides shielding for sensitive circuits and traces. It also provides a quiet reference potential for  
the control circuitry. The AGND and PGND pins must be connected to the ground plane using vias right next to  
the bypass capacitors. PGND pins are connected to the source of the internal low-side MOSFET 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 may bounce due to load variations. The PGND trace, as well as PVIN and SW  
traces, must be constrained to one side of the ground plane. The other side of the ground plane contains much  
less noise and must be used for sensitive routes.  
TI recommends providing adequate device heat sinking by using the exposed pad (EP) of the IC as the primary  
thermal path. Use a minimum 4 × 4 array of 10-mil thermal vias to connect the EP to the system ground plane for  
heat sinking. The vias must be evenly distributed under the exposed pad. Use as much copper as possible for  
system ground plane on the top and bottom layers for the best heat dissipation. TI recommends using a four-  
layer board with the copper thickness, starting from the top, as: 2 oz. / 1 oz. / 1 oz. / 2 oz. A four-layer board with  
enough copper thickness and proper layout provides low current conduction impedance, proper shielding and  
lower thermal resistance.  
These resources provide additional important guidelines for thermal PCB design:  
AN-2020 Thermal Design By Insight, Not Hindsight (SNVA419)  
AN-1520 A Guide to Board Layout for Best Thermal Resistance for Exposed Pad Packages (SNVA183)  
Semiconductor and IC Package Thermal Metrics (SPRA953)  
Thermal Design made Simple with LM43603 and LM43602 (SNVA719)  
PowerPAD™ Thermally Enhanced Package (SLMA002)  
PowerPAD Made Easy (SLMA004)  
Using New Thermal Metrics (SBVA025)  
Copyright © 2016, Texas Instruments Incorporated  
31  
LM53602, LM53603  
ZHCSFV3 NOVEMBER 2016  
www.ti.com.cn  
11.2 Layout Example  
Top Trace  
Bottom Trace  
VIA to Ground Plane  
INDUCTOR  
COUT  
COUT  
COUT  
CIN  
CIN  
CIN  
CVCC  
CBIAS  
EN  
SYNC  
FPWM  
RESET  
GND  
HEATSINK  
Figure 47. PCB Layout Example  
32  
版权 © 2016, Texas Instruments Incorporated  
LM53602, LM53603  
www.ti.com.cn  
ZHCSFV3 NOVEMBER 2016  
12 器件和文档支持  
12.1 器件支持  
12.1.1 Third-Party Products Disclaimer  
TI'S PUBLICATION OF INFORMATION REGARDING THIRD-PARTY PRODUCTS OR SERVICES DOES NOT  
CONSTITUTE AN ENDORSEMENT REGARDING THE SUITABILITY OF SUCH PRODUCTS OR SERVICES  
OR A WARRANTY, REPRESENTATION OR ENDORSEMENT OF SUCH PRODUCTS OR SERVICES, EITHER  
ALONE OR IN COMBINATION WITH ANY TI PRODUCT OR SERVICE.  
12.1.2 开发支持  
相关开发支持请参阅以下工具:  
针对无人机主辅助电源以及备用辅助电源的高密度效率解决方案  
针对具备所有保护功能的 12V 电池的 2.2MHz 切换同步分离电源参考设计  
具有集成 FET 15W 同步降压稳压器参考设计  
具备必需汽车保护功能的 30W ADAS 系统的系统级参考设计  
适用于汽车车身控制模块的 15W 系统级电源参考设计  
12.2 文档支持  
12.2.1 相关文档ꢀ  
相关文档如下:  
《使用新的热指标》(文献编号:SBVA025)。  
《采用前馈电容优化内部补偿 DC-DC 转换器的瞬态响应》(文献编号:SLVA289)  
《直流-直流转换器的传导 EMI 的简单成功案例》(文献编号:SNVA489)  
AN-1149《开关电源布局指南》 (文献编号:SNVA021)。  
AN-1229SIMPLE SWITCHER PCB 布局指南》(文献编号:SNVA054)  
《构建电源 - 布局注意事项》(文献编号:SLUP230)。  
《使用 LM4360x LM4600x 简化低辐射 EMI 布局》(文献编号:SNVA721)。  
AN-2020《富于洞见的热设计》(文献编号:SNVA419)。  
AN-1520《外露封装实现最佳热敏电阻特性的电路板布线指南》(文献编号:SNVA183)。  
《半导体和 IC 封装热指标》(文献编号:SPRA953)  
《使用 LM43603 LM43602 简化热设计》(文献编号:SNVA719)。  
PowerPAD ™耐热增强型封装》(文献编号:SLMA002)  
PowerPAD 速成》(文献编号:SLMA004)  
《使用新的热指标》(文献编号:SBVA025)。  
12.3 相关链接  
8  
接。  
列出了快速访问链接。范围包括技术文档、支持与社区资源、工具和软件,并且可以快速访问样片或购买链  
8. 相关链接  
器件  
产品文件夹  
请单击此处  
请单击此处  
样片与购买  
请单击此处  
请单击此处  
技术文档  
请单击此处  
请单击此处  
工具与软件  
请单击此处  
请单击此处  
支持与社区  
请单击此处  
请单击此处  
LM53602  
LM53603  
版权 © 2016, Texas Instruments Incorporated  
33  
 
LM53602, LM53603  
ZHCSFV3 NOVEMBER 2016  
www.ti.com.cn  
12.4 接收文档更新通知  
如需接收文档更新通知,请访问 www.ti.com.cn 网站上的器件产品文件夹。点击右上角的提醒我 (Alert me) 注册  
后,即可每周定期收到已更改的产品信息。有关更改的详细信息,请查阅已修订文档中包含的修订历史记录。  
12.5 社区资源  
The following links connect to TI community resources. Linked contents are provided "AS IS" by the respective  
contributors. They do not constitute TI specifications and do not necessarily reflect TI's views; see TI's Terms of  
Use.  
TI E2E™ Online Community TI's Engineer-to-Engineer (E2E) Community. Created to foster collaboration  
among engineers. At e2e.ti.com, you can ask questions, share knowledge, explore ideas and help  
solve problems with fellow engineers.  
Design Support TI's Design Support Quickly find helpful E2E forums along with design support tools and  
contact information for technical support.  
12.6 商标  
PowerPAD, PowerPAD, E2E are trademarks of Texas Instruments.  
WEBENCH is a registered trademark of Texas Instruments.  
Blu-ray Disc is a trademark of Blu-ray Disk Association.  
All other trademarks are the property of their respective owners.  
12.7 静电放电警告  
这些装置包含有限的内置 ESD 保护。 存储或装卸时,应将导线一起截短或将装置放置于导电泡棉中,以防止 MOS 门极遭受静电损  
伤。  
12.8 Glossary  
SLYZ022 TI Glossary.  
This glossary lists and explains terms, acronyms, and definitions.  
13 机械、封装和可订购信息  
以下页中包括机械、封装和可订购信息。这些信息是针对指定器件可提供的最新数据。这些数据会在无通知且不对  
本文档进行修订的情况下发生改变。欲获得该数据表的浏览器版本,请查阅左侧的导航栏。  
34  
版权 © 2016, Texas Instruments Incorporated  
重要声明  
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JESD48 最新标准中止提供任何产品和服务。客户在下订单前应获取最新的相关信息, 并验证这些信息是否完整且是最新的。所有产品的销售  
都遵循在订单确认时所提供的TI 销售条款与条件。  
TI 保证其所销售的组件的性能符合产品销售时 TI 半导体产品销售条件与条款的适用规范。仅在 TI 保证的范围内,且 TI 认为 有必要时才会使  
用测试或其它质量控制技术。除非适用法律做出了硬性规定,否则没有必要对每种组件的所有参数进行测试。  
TI 对应用帮助或客户产品设计不承担任何义务。客户应对其使用 TI 组件的产品和应用自行负责。为尽量减小与客户产品和应 用相关的风险,  
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对于 TI 的产品手册或数据表中 TI 信息的重要部分,仅在没有对内容进行任何篡改且带有相关授权、条件、限制和声明的情况 下才允许进行  
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及其后果、降低有可能造成人身伤害的故障的发生机率并采取适当的补救措施。客户将全额赔偿因 在此类安全关键应用中使用任何 TI 组件而  
TI 及其代理造成的任何损失。  
在某些场合中,为了推进安全相关应用有可能对 TI 组件进行特别的促销。TI 的目标是利用此类组件帮助客户设计和创立其特 有的可满足适用  
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只有那些 TI 特别注明属于军用等级或增强型塑料TI 组件才是设计或专门用于军事/航空应用或环境的。购买者认可并同 意,对并非指定面  
向军事或航空航天用途的 TI 组件进行军事或航空航天方面的应用,其风险由客户单独承担,并且由客户独 力负责满足与此类使用相关的所有  
法律和法规要求。  
TI 已明确指定符合 ISO/TS16949 要求的产品,这些产品主要用于汽车。在任何情况下,因使用非指定产品而无法达到 ISO/TS16949 要  
求,TI不承担任何责任。  
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应用  
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www.ti.com.cn/dataconverters  
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IMPORTANT NOTICE  
邮寄地址: 上海市浦东新区世纪大道1568 号,中建大厦32 楼邮政编码: 200122  
Copyright © 2016, 德州仪器半导体技术(上海)有限公司  
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)  
LM53602AMPWPR  
LM53602AMPWPT  
LM53603AMPWPR  
LM53603AMPWPT  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
HTSSOP  
HTSSOP  
HTSSOP  
HTSSOP  
PWP  
PWP  
PWP  
PWP  
16  
16  
16  
16  
2000 RoHS & Green  
250 RoHS & Green  
2000 RoHS & Green  
250 RoHS & Green  
NIPDAU  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
Level-3-260C-168 HR  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
L53602A  
NIPDAU  
NIPDAU  
NIPDAU  
L53602A  
L53603A  
L53603A  
(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  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals.  
TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 2  
PACKAGE OUTLINE  
PWP0016D  
PowerPADTM TSSOP - 1.2 mm max height  
S
C
A
L
E
2
.
2
5
0
PLASTIC SMALL OUTLINE  
6.6  
6.2  
TYP  
PIN 1 ID AREA  
A
14X 0.65  
16  
1
5.1  
4.9  
NOTE 3  
2X  
4.55  
8
9
0.30  
0.19  
4.5  
4.3  
16X  
0.1 C  
B
0.1  
C A B  
SEATING PLANE  
C
(0.15) TYP  
SEE DETAIL A  
2X (0.95)  
4X (0.3)  
NOTE 5  
4X 0.18 MAX  
NOTE 5  
0.25  
GAGE PLANE  
1.2 MAX  
3.40  
2.68  
0.75  
0.50  
0.15  
0.05  
0 - 8  
THERMAL  
PAD  
DETAIL A  
TYPICAL  
2.48  
1.75  
4223219/A 08/2016  
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. Reference JEDEC registration MO-153.  
5. Features may differ and may not be present.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
PWP0016D  
PowerPADTM TSSOP - 1.2 mm max height  
PLASTIC SMALL OUTLINE  
(3.4)  
NOTE 9  
SOLDER MASK  
DEFINED PAD  
(2.48)  
16X (1.5)  
SYMM  
SEE DETAILS  
1
16  
16X (0.45)  
(
0.2) TYP  
VIA  
(3.4)  
SYMM  
(5)  
NOTE 9  
(0.65) TYP  
(1.3 TYP)  
14X (0.65)  
8
9
(R0.05) TYP  
(1.1 TYP)  
METAL COVERED  
BY SOLDER MASK  
(5.8)  
LAND PATTERN EXAMPLE  
SCALE:10X  
METAL UNDER  
SOLDER MASK  
SOLDER MASK  
METAL  
SOLDER MASK  
OPENING  
OPENING  
0.05 MIN  
AROUND  
0.05 MAX  
AROUND  
SOLDER MASK  
DEFINED  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
NOT TO SCALE  
4223219/A 08/2016  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
8. 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).  
9. Size of metal pad may vary due to creepage requirement.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
PWP0016D  
PowerPADTM TSSOP - 1.2 mm max height  
PLASTIC SMALL OUTLINE  
(2.48)  
BASED ON  
0.125 THICK  
STENCIL  
16X (1.5)  
(R0.05) TYP  
1
16  
16X (0.45)  
(3.4)  
SYMM  
BASED ON  
0.125 THICK  
STENCIL  
14X (0.65)  
8
9
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  
2.77 X 3.8  
2.48 X 3.4 (SHOWN)  
2.26 X 3.1  
0.125  
0.15  
0.175  
2.1 X 2.87  
4223219/A 08/2016  
NOTES: (continued)  
10. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
11. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
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