LMR23630APDRRT [TI]

SIMPLE SWITCHER® 36V、3A 同步降压转换器 | DRR | 12 | -40 to 125;
LMR23630APDRRT
型号: LMR23630APDRRT
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

SIMPLE SWITCHER® 36V、3A 同步降压转换器 | DRR | 12 | -40 to 125

转换器
文件: 总45页 (文件大小:3301K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
LMR23630  
ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
LMR23630 SIMPLE SWITCHER® 36V3A 同步降压转换器  
1 特性  
3 说明  
4V 36V 的输入电压范围  
3A 持续输出电流  
• 集成同步整流  
• 电流模式控制  
• 最短导通时间60ns  
• 内置补偿功能便于使用  
400kHz 开关频率和可调频率选项  
PFM 和强PWM 模式选项  
• 与外部时钟频率同步  
• 对PFM 选项无负载条件下的静态电流75µA  
• 软启动至预偏置负载  
• 支持高占空比运行模式  
• 精密使能输入  
• 具有断续模式的输出短路保护  
• 过热保护  
PowerPAD8 HSOIC 封装  
PowerPAD12 WSON 可湿性侧面封装  
• 使LMZM33603 模块缩短产品上市时间  
• 使LMR23625 并借WEBENCH® Power  
Designer 创建定制设计方案  
LMR23630 SIMPLE SWITCHER® 是一款易于使用的  
36V3A 同步降压稳压器具有 4V 36V 的宽输入  
电压范围适用于从非稳压源进行电源调节的各种工业  
应用。该器件采用峰值电流模式控制来实现简单控制环  
路补偿和逐周期电流限制。它具有 75μA 的静态电  
因此适用于电池供电型系统。凭借 2μA 的超低关  
断电流可进一步延长电池使用寿命。内部环路补偿意  
味着用户不用承担设计环路补偿组件的枯燥工作。这样  
还能够最大限度地减少外部元件数。该器件可选用恒定  
频率 FPWM 模式在轻载条件下实现小输出电压纹  
波。该器件的扩展系列产品 (HSOIC) 能够以引脚对引  
脚兼容的封装可用于实现简单且优化的 PCB 布局)  
提供负载电流为 1A (LMR23610) 2.5A (LMR23625)  
的选件。利用精密使能端输入可以简化稳压器控制和系  
统电源时序。保护特性包括逐周期电流限制、间断模式  
短路保护和过多功率耗散而引起的热关断。  
器件信息  
器件型(1)  
LMR23630  
封装尺寸标称值)  
4.89mm × 3.90mm  
3.00mm × 3.00mm  
封装  
HSOIC (8)  
WSON (12)  
2 应用  
(1) 如需了解所有不同可用选件的详细器件型号请参阅数据表末  
尾的可订购产品附录。  
工厂和楼宇自动化系统PLC CPUHVAC 控制、  
电梯控制  
资产跟踪  
通用宽输入电压调节  
VIN up to 36 V  
100  
90  
80  
70  
60  
CIN  
VIN  
BOOT  
SW  
EN/SYNC  
AGND  
CBOOT  
L
VOUT  
RFBT  
COUT  
RFBB  
VCC  
FB  
CVCC  
PGND  
50  
VOUT = 5 V  
VOUT = 3.3 V  
40  
0.0001  
简化版原理图  
0.001  
0.01  
0.1  
1
10  
IOUT (A)  
D001  
效率与负载间的关VIN = 12VPFM 选项  
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: SNVSAH2  
 
 
 
 
 
LMR23630  
www.ti.com.cn  
ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
Table of Contents  
8.4 Device Functional Modes..........................................20  
9 Application and Implementation..................................21  
9.1 Application Information............................................. 21  
9.2 Typical Applications.................................................. 21  
10 Power Supply Recommendations..............................28  
11 Layout...........................................................................28  
11.1 Layout Guidelines................................................... 28  
11.2 Layout Example...................................................... 29  
11.3 Compact Layout for EMI Reduction........................ 29  
11.4 Ground Plane and Thermal Considerations............30  
11.5 Feedback Resistors................................................ 31  
12 Device and Documentation Support..........................32  
12.1 Device Support....................................................... 32  
12.2 接收文档更新通知................................................... 32  
12.3 支持资源..................................................................32  
12.4 Trademarks.............................................................32  
12.5 静电放电警告.......................................................... 32  
12.6 术语表..................................................................... 32  
13 Mechanical, Packaging, and Orderable  
1 特性................................................................................... 1  
2 应用................................................................................... 1  
3 说明................................................................................... 1  
4 Revision History.............................................................. 2  
5 Device Comparison Table...............................................4  
6 Pin Configuration and Functions...................................4  
Pin Functions.................................................................... 5  
7 Specifications.................................................................. 6  
7.1 Absolute Maximum Ratings........................................ 6  
7.2 ESD Ratings............................................................... 6  
7.3 Recommended Operating Conditions.........................6  
7.4 Thermal Information....................................................7  
7.5 Electrical Characteristics.............................................7  
7.6 Timing Requirements..................................................9  
7.7 Switching Characteristics............................................9  
7.8 Typical Characteristics..............................................10  
8 Detailed Description......................................................12  
8.1 Overview...................................................................12  
8.2 Functional Block Diagram.........................................12  
8.3 Feature Description...................................................13  
Information.................................................................... 32  
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 D (February 2018) to Revision E (July 2020)  
Page  
• 更新了整个文档中的表格、图和交叉参考的编号格式。..................................................................................... 1  
• 向1 添加LMZM33630 要点........................................................................................................................ 1  
Changes from Revision C (June 2017) to Revision D (February 2018)  
Page  
• 在应用中将“可编程逻辑控制器电源”更改为“工厂和楼宇自动化系统.........................................................1  
• 删除了“多功能打印机和工业电源”并重新编写了.................................................................................... 1  
• 将“应用”中的“HVAC 系统”更改为“通用宽输入电压调节”....................................................................... 1  
Added "2.2-µF, 16-V" for VCC pin bypass capacitor ..........................................................................................5  
Change the Max Recommend Operating Condition for Iout to be 3-A from 2.5-A ............................................ 6  
Consolidating all the common EC table characteristic between HSOIC and WSON, for example Operation  
Input Voltage, VIN_UVLO, IEN and Mnimum turn-on time ................................................................................. 7  
Changed Typical Value for VIN_UVLO Rising threshold typical from 3.6-V to 3.7-V and minimum Falling  
threshold from 3-V to 2.9-V ................................................................................................................................7  
Changed the operating from "4.5-V" ... to "4-V" in Device Functional Modes ..................................................20  
Changed from VOUT = 7 V to 36 V to VIN = 7 V to 36 V on 9-9 ................................................................... 26  
Changes from Revision B (April 2017) to Revision C (June 2017)  
Page  
• 删除了“汽车电池稳压”且重新编写了...................................................................................................... 1  
• 添加了“WSON 封装和选项”............................................................................................................................1  
Added Device Comparison Table ...................................................................................................................... 4  
Change EN Abs Max to EN/SYNC Abs Max ..................................................................................................... 6  
Updating ESD Ratings to include HSOIC and WSON .......................................................................................6  
Corrected Equation 17 denominator from "(VOUT x VOS)" to "(VOUT + VOS)"....................................................23  
clarified equations Equation 23 and Equation 24 ............................................................................................ 30  
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ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
Changes from Revision A (July 2016) to Revision B (April 2017)  
Page  
Changed spec from 6.0 to 6.2 for max under Current Limit................................................................................7  
Changed spec from 4.2 to 4.6 for max under Current Limit................................................................................7  
Changes from Revision * (December 2015) to Revision A (July 2016)  
Page  
• 将“产品预发布”更改为“量产数据”并添加了所有其余部分.......................................................................1  
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ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
5 Device Comparison Table  
ADJUSTABLE  
FIXED 400 kHz FREQUENCY  
RESISTOR  
PACKAGE  
PART NUMBER  
POWER GOOD FPWM  
LMR23630ADDA  
yes  
yes  
no  
no  
no  
no  
no  
no  
yes  
no  
HSOIC (8)  
LMR23630AFDDA  
LMR23630DRR  
yes  
yes  
no  
no  
WSON (12) (Pin 6 is RT)  
LMR23630FDRR  
LMR23630APDRR  
no  
no  
yes  
no  
WSON (12) (Pin 6 is PGOOD)  
yes  
yes  
6 Pin Configuration and Functions  
6-1. DRR Package 12-Pin WSON With RT and Thermal Pad Top View  
6-2. DRR Package 12-Pin WSON With PGOOD and Thermal Pad Top View  
SW  
1
8
PGND  
BOOT  
VCC  
FB  
2
3
4
7
6
5
VIN  
Thermal Pad  
(9)  
AGND  
EN/SYNC  
6-3. DDA Package 8-Pin HSOIC Top View  
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ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
Pin Functions  
PIN  
I/O (1)  
DESCRIPTION  
HSOI WSON With  
WSON With  
PGOOD  
NAME  
SW  
C
RT  
Switching output of the regulator. Internally connected to both power  
MOSFETs. Connect to power inductor.  
1
1, 2  
1, 2  
3
P
P
Boot-strap capacitor connection for high-side driver. Connect a high quality  
100nF or 470nF capacitor from BOOT to SW.  
2
3
3
4
BOOT  
Internal bias supply output for bypassing. Connect 2.2-µF, 16-V bypass  
capacitor from this pin to AGND. Do not connect external loading to this  
pin. Never short this pin to ground during operation.  
4
VCC  
P
Feedback input to regulator, connect the midpoint of feedback resistor  
divider to this pin.  
4
5
6
5
N/A  
6
FB  
RT  
A
A
A
Connect a resistor RT from this pin to AGND to program switching  
frequency. Leave floating for 400-kHz default switching frequency.  
N/A  
N/A  
Open drain output for power-good flag. Use a 10-kΩto 100-kΩpullup  
resistor to logic rail or other DC voltage no higher than 12 V.  
N/A  
PGOOD  
Enable input to regulator. High = On, Low = Off. Can be connected to VIN.  
Do not float. Adjust the input undervoltage lockout with two resistors. The  
internal oscillator can be synchronized to an external clock by coupling a  
positive pulse into this pin through a small coupling capacitor. See 8.3.4  
for details.  
5
8
8
EN/SYNC  
A
Analog ground pin. Ground reference for internal references and logic.  
Connect to system ground.  
6
7
7
7
AGND  
VIN  
G
P
9, 10  
9, 10  
Input supply voltage.  
Power ground pin, connected internally to the low side power FET.  
8
12  
12  
PGND  
G
G
Connect to system ground, PAD, AGND, ground pins of CIN and COUT  
Path to CIN must be as short as possible.  
.
Low impedance connection to AGND. Connect to PGND on PCB. Major  
heat dissipation path of the die. Must be used for heat sinking to ground  
plane on PCB.  
9
13  
11  
13  
11  
PAD  
NC  
N/A  
N/A Not for use. Leave this pin floating.  
(1) A = Analog, P = Power, G = Ground.  
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ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
7 Specifications  
7.1 Absolute Maximum Ratings  
Over the recommended operating junction temperature range of 40°C to +125°C (unless otherwise noted) (1)  
PARAMETER  
MIN  
0.3  
5.5  
0.3  
0.3  
0.3  
0.3  
1  
MAX  
UNIT  
VIN to PGND  
42  
VIN+ 0.3  
4.5  
EN/SYNC to AGND  
FB to AGND  
Input voltages  
V
RT to AGND  
4.5  
PGOOD to AGND  
AGND to PGND  
15  
0.3  
SW to PGND  
VIN + 0.3  
42  
SW to PGND less than 10 ns transients  
BOOT to SW  
5  
Output voltages  
V
5.5  
0.3  
0.3  
40  
65  
4.5(2)  
150  
VCC to AGND  
TJ  
Junction temperature  
Storage temperature  
°C  
°C  
Tstg  
150  
(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.  
(2) In shutdown mode, the VCC to AGND maximum value is 5.25 V.  
7.2 ESD Ratings  
VALUE  
UNIT  
Human-body model (HBM) for HSOIC (1)  
±2000  
Human-body model (HBM) for WSON with RT and  
PGOOD(1)  
±2500  
V(ESD)  
Electrostatic discharge  
V
Charged-device model (CDM) for HSOIC and WSON RT(2)  
Charged-device model (CDM) for WSON PGOOD(2)  
±1000  
±750  
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.  
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.  
7.3 Recommended Operating Conditions  
Over the recommended operating junction temperature range of 40°C to +125°C (unless otherwise noted) (1)  
MIN  
MAX UNIT  
VIN  
4
36  
36  
1.2  
12  
1
EN/SYNC  
5  
0.3  
0.3  
0
Input voltage  
V
FB  
PGOOD  
Input current  
Output voltage  
Output current  
Temperature  
PGOOD pin current  
mA  
V
VOUT  
1
28  
3
IOUT  
0
A
Operating junction temperature, TJ  
125  
°C  
40  
(1) Operating Ratings indicate conditions for which the device is intended to be functional, but do not ensure specific performance limits.  
For ensured specifications, see 7.5.  
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ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
7.4 Thermal Information  
THERMAL METRIC (1) (2)  
DDA (8 PINS) DRR (12 PINS)  
UNIT  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
°C/W  
RθJA  
Junction-to-ambient thermal resistance  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
Junction-to-case (top) thermal resistance  
Junction-to-case (bottom) thermal resistance  
Junction-to-board thermal resistance  
42.0  
5.9  
41.5  
0.3  
ψJT  
23.4  
45.8  
3.6  
16.5  
39.1  
3.4  
ψJB  
RθJC(top)  
RθJC(bot)  
RθJB  
23.4  
16.3  
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application  
report.  
(2) Determine power rating at a specific ambient temperature TA with a maximum junction temperature (TJ) of 125°C (see 7.3).  
7.5 Electrical Characteristics  
Limits apply over the recommended operating junction temperature (TJ) range of 40°C to +125°C, unless otherwise stated.  
Minimum and maximum limits are specified 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.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
POWER SUPPLY (VIN PIN)  
VIN  
Operation input voltage  
4
3.3  
2.9  
36  
3.9  
3.5  
V
V
VIN_UVLO  
Undervoltage lockout thresholds  
Rising threshold  
3.7  
3.3  
Falling threshold  
VEN = 0 V, VIN = 12 V, TJ = 40°C to  
125°C  
ISHDN  
IQ  
Shutdown supply current  
2
4
μA  
μA  
75  
Operating quiescent current (non-  
switching)  
VIN =12 V, VFB = 1.1 V, TJ = 40°C to  
125°C, PFM mode  
ENABLE (EN/SYNC PIN)  
VEN_H  
Enable rising threshold voltage  
1.4  
0.4  
1.55  
0.4  
1.7  
V
V
VEN_HYS  
VWAKE  
Enable hysteresis voltage  
Wake-up threshold  
V
nA  
nA  
μA  
μA  
VIN = 4 V to 36 V, VEN= 2 V  
VIN = 4 V to 36 V, VEN= 36 V  
10  
100  
1
IEN  
Input leakage current at EN pin  
VOLTAGE REFERENCE (FB PIN)  
VIN = 4.0 V to 36 V, TJ = 25 °C  
VIN = 4.0 V to 36 V, TJ = 40°C to 125°C  
VFB= 1 V  
0.985  
0.98  
1
1
1.015  
1.02  
V
V
VREF  
Reference voltage  
ILKG_FB  
Input leakage current at FB pin  
10  
nA  
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Limits apply over the recommended operating junction temperature (TJ) range of 40°C to +125°C, unless otherwise stated.  
Minimum and maximum limits are specified 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.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX UNIT  
POWER GOOD (PGOOD PIN)  
Power-good flag overvoltage  
tripping threshold  
VPG_OV  
% of reference voltage  
104%  
92%  
107%  
94%  
110%  
Power-good flag undervoltage  
tripping threshold  
VPG_UV  
% of reference voltage  
% of reference voltage  
96.5%  
Power-good flag recovery  
hysteresis  
VPG_HY S  
VIN_PG_MIN  
1.5%  
Minimum VIN for valid PGOOD  
output  
50 μA pullup to PGOOD pin, VEN = 0 V, TJ  
= 25°C  
1.5  
0.4  
0.4  
V
V
V
50 μA pullup to PGOOD pin, VIN = 1.5 V,  
VEN = 0 V  
VPG_LOW  
PGOOD low level output voltage  
0.5 mA pullup to PGOOD pin, VIN = 13.5 V,  
VEN = 0 V  
INTERNAL LDO (VCC PIN)  
VCC  
Internal LDO output voltage  
4.1  
3.2  
2.8  
V
V
Rising threshold  
Falling threshold  
2.8  
2.4  
3.6  
3.2  
VCC undervoltage lockout  
thresholds  
VCC_UVLO  
CURRENT LIMIT  
IHS_LIMIT Peak inductor current limit  
HSOIC package  
3.8  
4
5
5.5  
6.2  
6.6  
4.6  
4.2  
A
A
WSON package  
HSOIC package  
2.9  
2.9  
3.6  
ILS_LIMIT  
Valley inductor current limit  
Zero cross current limit  
WSON package  
3.6  
IL_ZC  
HSOIC and WSON package  
A
A
0.04  
Negative current limit (FPWM  
option)  
IL_NEG  
SOIC and WSON package  
2.7  
2  
1.3  
INTEGRATED MOSFETS  
RDS_ON_HS High-side MOSFET ON-resistance  
SOIC package, VIN = 12 V, IOUT = 1 A  
WSON package, VIN = 12 V, IOUT = 1 A  
SOIC package, VIN = 12 V, IOUT = 1 A  
WSON package, VIN = 12 V, IOUT = 1 A  
185  
160  
105  
95  
mΩ  
mΩ  
RDS_ON_LS  
Low-side MOSFET ON-resistance  
THERMAL SHUTDOWN  
TSHDN Thermal shutdown threshold  
THYS Hysteresis  
162  
170  
15  
178  
°C  
°C  
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ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
7.6 Timing Requirements  
Over the recommended operating junction temperature range of 40°C to +125°C (unless otherwise noted)  
MIN  
NOM  
MAX UNIT  
HICCUP MODE  
Number of cycles that LS current  
(1)  
NOC  
64  
Cycles  
ms  
limit is tripped to enter hiccup mode  
SOIC package  
5
TOC  
Hiccup retry delay time  
WSON package  
10  
SOFT START  
SOIC package, the time of internal  
reference to increase from 0 V to 1 V  
ms  
ms  
2
6
TSS  
Internal soft-start time  
WSON package, the time of internal  
reference to increase from 0 V to 1 V  
POWER GOOD  
Power-good flag rising transition  
TPGOOD_RISE  
150  
18  
μs  
μs  
deglitch delay  
Power-good flag falling transition  
deglitch delay  
TPGOOD_FALL  
(1) Ensured by design.  
7.7 Switching Characteristics  
Over the recommended operating junction temperature range of 40°C to +125°C (unless otherwise noted)  
PARAMETER  
MIN  
TYP  
MAX UNIT  
SW (SW PIN)  
TON_MIN  
Minimum turnon time  
Minimum turnoff time  
WSON package  
60  
90  
ns  
ns  
(1)  
TOFF_MIN  
100  
OSCILLATOR (RT and EN/SYNC PIN)  
fSW_DEFAULT Oscillator default frequency  
Minimum adjustable frequency  
Fixed frequency version or RT pin open  
circuit  
340  
400  
460 kHz  
150  
1750  
200  
200  
250 kHz  
2425 kHz  
2200 kHz  
RT = 198 kwith 1% accuracy  
RT = 17.8 kwith 1% accuracy  
fADJ  
Maximum adjustable frequency  
SYNC frequency range  
2150  
fSYNC  
Amplitude of SYNC clock AC  
signal (measured at SYNC pin)  
VSYNC  
2.8  
5.5  
V
Minimum sync clock ON-time  
and OFF-time  
TSYNC_MIN  
100  
ns  
(1) Specified by design.  
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7.8 Typical Characteristics  
Unless otherwise specified the following conditions apply: VIN = 12 V, fSW = 400 kHz, L = 8.2 µH, COUT = 150 µF,  
TA = 25°C.  
100  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
100  
90  
80  
70  
60  
50  
40  
30  
20  
10  
0
PFM, VIN = 12 V  
PFM, VIN = 24 V  
PFM, VIN = 36 V  
FPWM, VIN = 12 V  
FPWM, VIN = 24 V  
FPWM, VIN = 36 V  
PFM, VIN = 12 V  
PFM, VIN = 24 V  
PFM, VIN = 36 V  
FPWM, VIN = 12 V  
FPWM, VIN = 24 V  
FPWM, VIN = 36 V  
1E-5  
0.0001  
0.001  
0.01  
IOUT (A)  
0.1  
1
10  
1E-5  
0.0001  
0.001  
0.01  
IOUT (A)  
0.1  
1
10  
D001  
D002  
fSW = 400 kHz  
VOUT = 5 V  
fSW = 400 kHz  
VOUT = 3.3 V  
7-1. Efficiency vs Load Current  
7-2. Efficiency vs Load Current  
100  
90  
80  
70  
60  
50  
40  
100  
90  
80  
70  
60  
50  
40  
PFM, VIN = 12 V  
PFM, VIN = 24 V  
PFM, VIN = 36 V  
FPWM, VIN = 12 V  
PFM, VIN = 12 V  
PFM, VIN = 24 V  
PFM, VIN = 36 V  
FPWM, VIN = 12 V  
30  
20  
30  
20  
FPWM, VIN = 24 V  
FPWM, VIN = 36 V  
FPWM, VIN = 24 V  
FPWM, VIN = 36 V  
10  
0
10  
0
1E-5  
0.0001  
0.001  
0.01  
IOUT (A)  
0.1  
1
10  
1E-5  
0.0001  
0.001  
0.01  
IOUT (A)  
0.1  
1
10  
D003  
D004  
fSW = 200 kHz (Sync)  
VOUT = 5 V  
fSW = 200 kHz (Sync)  
VOUT = 3.3 V  
7-3. Efficiency vs Load Current  
7-4. Efficiency vs Load Current  
5.09  
5.08  
5.07  
5.06  
5.05  
5.04  
5.03  
5.02  
5.01  
5
5.015  
5.01  
5.005  
5
VIN = 12 V  
VIN = 24 V  
VIN = 36 V  
VIN = 12 V  
VIN = 24 V  
VIN = 36 V  
4.99  
0
0.5  
1
1.5  
IOUT (A)  
2
2.5  
3
0
0.5  
1
1.5  
IOUT (A)  
2
2.5  
3
D005  
D004  
FPWM Version  
VOUT = 5 V  
PFM version  
VOUT = 5 V  
7-6. Load Regulation  
7-5. Load Regulation  
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5.5  
3.6  
3.3  
3
5
4.5  
4
2.7  
IOUT = 0.5 A  
IOUT = 1.0 A  
IOUT = 2.0 A  
IOUT = 3.0 A  
IOUT = 0.5 A  
IOUT = 1.0 A  
IOUT = 2.0 A  
IOUT = 3.0 A  
3.5  
3
4
2.4  
3.3  
4.5  
5
VIN (V)  
5.5  
6
3.5  
3.7  
3.9  
VIN (V)  
4.1  
4.3  
4.5  
D006  
D007  
VOUT = 5 V  
VOUT = 3.3 V  
7-7. Dropout Curve  
7-8. Dropout Curve  
80  
75  
70  
65  
3.67  
3.66  
3.65  
3.64  
3.63  
3.62  
3.61  
60  
-50  
-50  
0
50  
Temperature (°C)  
100  
150  
0
50  
Temperature (°C)  
100  
150  
D008  
D009  
VIN = 12 V  
VFB = 1.1 V  
7-10. VIN UVLO Rising Threshold vs Junction  
7-9. IQ vs Junction Temperature  
Temperature  
0.425  
0.42  
5.5  
LS Limit  
HS Limit  
5
4.5  
4
0.415  
3.5  
0.41  
3
-50  
-50  
0
50  
Temperature (°C)  
100  
150  
0
50  
Temperature (°C)  
100  
150  
D010  
D011  
VIN = 12 V  
7-11. VIN UVLO Hysteresis vs Junction  
7-12. HS and LS Current Limit vs Junction  
Temperature  
Temperature  
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8 Detailed Description  
8.1 Overview  
The LMR23630 SIMPLE SWITCHER® regulator is an easy-to-use synchronous step-down DC-DC converter  
operating from 4-V to 36-V supply voltage. The device delivers up to 3-A DC load current with good thermal  
performance in a small solution size. For both the HSOIC and WSON packages, an extended family is available  
in multiple current options from 1 A to 3 A in pin-to-pin compatible packages.  
The LMR23630 employs constant frequency peak-current-mode control. The device enters PFM mode at light  
load to achieve high efficiency. A user-selectable FPWM version is provided to achieve low output voltage ripple,  
tight output voltage regulation, and constant switching frequency. The switching frequency is 400 kHz for the  
fixed-frequency version. For the version which has RT pin, the switching frequency is adjustable from 200 kHz to  
2.2 MHz. The device is internally compensated, which reduces design time and requires few external  
components. The LMR23630 is capable of synchronization to an external clock within the range of 200 kHz to  
2.2 MHz.  
Additional features such as precision enable, power-good flag, and internal soft-start provide a flexible and easy-  
to-use solution for a wide range of applications. Protection features include thermal shutdown, VIN and VCC  
undervoltage lockout, cycle-by-cycle current limit, and hiccup-mode short-circuit protection.  
The family requires very few external components and has a pinout designed for simple, optimum PCB layout.  
8.2 Functional Block Diagram  
VCC  
EN/SYNC  
SYNC Signal  
SYNC  
Detector  
VCC  
Enable  
LDO  
VIN  
Precision  
Enable  
CBOOT  
Internal  
SS  
HS I Sense  
EA  
REF  
Rc  
Cc  
TSD  
UVLO  
(PGOOD)  
PWM CONTROL LOGIC  
PFM  
Detector  
SW  
OV/UV  
Detector  
FB  
Slope  
Comp  
Freq  
Foldback  
Zero  
Cross  
HICCUP  
Detector  
AGND  
SYNC Signal  
(RT)  
Oscillator  
LS I Sense  
FB  
PGND  
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8.3 Feature Description  
8.3.1 Fixed Frequency Peak Current Mode Control  
The following operating description of the LMR23630 refers to 8.2 and to the waveforms in 8-1. The  
LMR23630 is a step-down synchronous buck regulator with integrated high-side (HS) and low-side (LS) switches  
(synchronous rectifier). The LMR23630 supplies a regulated output voltage by turning on the HS and LS NMOS  
switches with controlled duty cycle. During high-side switch ON-time, the SW pin voltage swings up to  
approximately VIN, and the inductor current iL increase with linear slope (VIN VOUT) / L. When the HS switch is  
turned off by the control logic, the LS switch is turned on after an anti-shoot-through dead time. Inductor current  
discharges through the LS switch with a slope of VOUT / L. The control parameter of a buck converter is  
defined as duty cycle D = tON / TSW, where tON is the high-side switch ON-time and TSW is the switching period.  
The regulator control loop maintains a constant output voltage by adjusting the duty cycle D. In an ideal buck  
converter, where losses are ignored, D is proportional to the output voltage and inversely proportional to the  
input voltage: D = VOUT / VIN.  
VSW  
D = tON/ TSW  
VIN  
tON  
tOFF  
t
0
-VD  
TSW  
iL  
ILPK  
IOUT  
DiL  
t
0
8-1. SW Node and Inductor Current Waveforms in Continuous Conduction Mode (CCM)  
The LMR23630 employs fixed-frequency peak-current-mode control. A voltage feedback loop is used to get  
accurate DC voltage regulation by adjusting the peak current command based on voltage offset. The peak  
inductor current is sensed from the high-side switch and compared to the peak current threshold to control the  
ON-time of the high-side switch. The voltage feedback loop is internally compensated, which allows for fewer  
external components, makes it easy to design, and provides stable operation with almost any combination of  
output capacitors. The regulator operates with fixed switching frequency at normal load condition. At light load  
condition, the LMR23630 operates in PFM mode to maintain high efficiency (PFM option) or in FPWM mode for  
low output-voltage ripple, tight output-voltage regulation, and constant switching frequency (FPWM option).  
8.3.2 Adjustable Frequency  
The switching frequency can be programmed for the adjustable-switching-frequency version of LMR23630 by  
the impedance RT from the RT pin to ground. The frequency is inversely proportional to the RT resistance. The  
RT pin can be left floating and the LMR23630 operates at 400-kHz default switching frequency. The RT pin is not  
designed to be shorted to ground. For a desired frequency, typical RT resistance can be found by 方程式 1. 表  
8-1 gives typical RT values for a given fSW  
.
RT(kΩ) = 40200 / fSW(kHz) 0.6  
(1)  
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250  
200  
150  
100  
50  
0
0
500  
1000  
1500  
2000  
2500  
Switching Frequency (kHz)  
C008  
8-2. RT vs Frequency Curve  
8-1. Typical Frequency Setting RT Resistance  
fSW (kHz)  
RT (k)  
200  
350  
200  
115  
500  
78.7  
53.6  
39.2  
26.1  
19.6  
17.8  
750  
1000  
1500  
2000  
2200  
8.3.3 Adjustable Output Voltage  
A precision 1-V reference voltage is used to maintain a tightly regulated output voltage over the entire operating  
temperature range. The output voltage is set by a resistor divider from output voltage to the FB pin. TI  
recommends using 1% tolerance resistors with a low temperature coefficient for the FB divider. Select the  
lowside resistor RFBB for the desired divider current and use Equation 2 to calculate high-side RFBT. RFBT in the  
range from 10 kto 100 kis recommended for most applications. A lower RFBT value can be used if static  
loading is desired to reduce VOUT offset in PFM operation. Lower RFBT will reduce efficiency at very light load.  
Less static current goes through a larger RFBT and might be more desirable when light load efficiency is critical.  
However, RFBT larger than 1 MΩis not recommended because it makes the feedback path more susceptible to  
noise. Larger RFBT value requires more carefully designed feedback path on the PCB. The tolerance and  
temperature variation of the resistor dividers affect the output voltage regulation.  
V
OUT  
R
FBT  
FBB  
FB  
R
8-3. Output Voltage Setting  
VOUT - VREF  
VREF  
RFBT  
=
ìRFBB  
(2)  
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8.3.4 Enable/Sync  
The voltage on the EN/SYNC pin controls the ON or OFF operation of LMR23630. A voltage less than 1 V  
(typical) shuts down the device while a voltage higher than 1.6 V (typical) is required to start the regulator. The  
EN/SYNC pin is an input and cannot be left open or floating. The simplest way to enable the operation of the  
LMR23630 is to connect the EN to VIN. This allows self-start-up of the LMR23630 when VIN is within the  
operation range.  
Many applications can benefit from the employment of an enable divider RENT and RENB (8-4) to establish a  
precision system UVLO level for the converter. System UVLO can be used for supplies operating from utility  
power as well as battery power. It can be used for sequencing, ensuring reliable operation, or supply protection,  
such as a battery discharge level. An external logic signal can also be used to drive EN input for system  
sequencing and protection.  
VIN  
RENT  
EN/SYNC  
RENB  
8-4. System UVLO by Enable Divider  
The EN pin also can be used to synchronize the internal oscillator to an external clock. The internal oscillator can  
be synchronized by AC-coupling a positive edge into the EN pin. The AC-coupled peak-to-peak voltage at the  
EN pin must exceed the SYNC amplitude threshold of 2.8 V (typical) to trip the internal synchronization pulse  
detector, and the minimum SYNC clock ON-time and OFF-time must be longer than 100 ns (typical). A 3.3-V or  
a higher amplitude pulse signal coupled through a 1-nF capacitor CSYNC is a good starting point. Keeping RENT //  
RENB (RENT parallel with RENB) in the 100 krange is a good choice. RENT is required for this synchronization  
circuit, but RENB can be left unmounted if system UVLO is not needed. LMR23630 switching action can be  
synchronized to an external clock from 200 kHz to 2.2 MHz. 8-6 and 8-7 show the device synchronized to  
an external system clock.  
VIN  
RENT  
CSYNC  
EN/SYNC  
RENB  
Clock  
Source  
8-5. Synchronize to External Clock  
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8-6. Synchronizing in PWM Mode  
8-7. Synchronizing in PFM Mode  
8.3.5 VCC, UVLO  
The LMR23630 integrates an internal LDO to generate VCC for control circuitry and MOSFET drivers. The  
nominal voltage for VCC is 4.1 V. The VCC pin is the output of an LDO and must be properly bypassed. Place a  
high-quality ceramic capacitor with a value of 2.2 µF to 10 µF, 16 V or higher rated voltage as close as possible  
to VCC and grounded to the exposed PAD and ground pins. The VCC output pin must not be loaded, or shorted  
to ground during operation. Shorting VCC to ground during operation may cause damage to the LMR23630.  
VCC undervoltage lockout (UVLO) prevents the LMR23630 from operating until the VCC voltage exceeds 3.3 V  
(typical). The VCC UVLO threshold has 400 mV (typical) of hysteresis to prevent undesired shutdown due to  
temporary VIN drops.  
8.3.6 Minimum ON-time, Minimum OFF-time and Frequency Foldback at Dropout Conditions  
Minimum ON-time, TON_MIN, is the smallest duration of time that the HS switch can be on. TON_MIN is typically 60  
ns in the LMR23630. Minimum OFF-time, TOFF_MIN, is the smallest duration that the HS switch can be off.  
TOFF_MIN is typically 100 ns in the LMR23630. In CCM operation, TON_MIN and TOFF_MIN limit the voltage  
conversion range given a selected switching frequency.  
The minimum duty cycle allowed is:  
DMIN = TON_MIN × fSW  
(3)  
And the maximum duty cycle allowed is:  
DMAX = 1 TOFF_MIN × fSW  
(4)  
Given fixed TON_MIN and TOFF_MIN, the higher the switching frequency the narrower the range of the allowed duty  
cycle. In the LMR23630, a frequency foldback scheme is employed to extend the maximum duty cycle when  
TOFF_MIN is reached. The switching frequency decreases once longer duty cycle is needed under low VIN  
conditions. Wide range of frequency foldback allows the LMR23630 output voltage stay in regulation with a  
much lower supply voltage VIN. This leads to a lower effective dropout voltage.  
Given an output voltage, the choice of the switching frequency affects the allowed input voltage range, solution  
size and efficiency. The maximum operation supply voltage can be found by:  
VOUT  
V
=
IN_MAX  
f
ì TON_MIN  
(
)
SW  
(5)  
At lower supply voltage, the switching frequency decreases once TOFF_MIN is tripped. The minimum VIN without  
frequency foldback can be approximated by:  
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VOUT  
V
=
IN_MIN  
1- f  
(
ì TOFF _MIN  
)
SW  
(6)  
Taking considerations of power losses in the system with heavy load operation, VIN_MAX is higher than the result  
calculated in 方程5. With frequency foldback, VIN_MIN is lowered by decreased fSW  
.
450  
400  
350  
300  
250  
200  
150  
IOUT = 0.5 A  
IOUT = 1.0 A  
100  
IOUT = 2.0 A  
IOUT = 3.0 A  
50  
0
4.6  
4.8  
5
5.2  
5.4  
5.6  
5.8  
6
6.2  
6.4  
VIN (V)  
D013  
8-8. Frequency Foldback at Dropout (VOUT = 5 V, fSW = 400 kHz)  
8.3.7 Power Good (PGOOD)  
The power-good version of LMR23630 has a built in power-good flag shown on PGOOD pin to indicate whether  
the output voltage is within its regulation level. The PGOOD signal can be used for start-up sequencing of  
multiple rails or fault protection. The PGOOD pin is an open-drain output that requires a pullup resistor to an  
appropriate DC voltage. Voltage detected by the PGOOD pin must never exceed 15 V, and limit the maximum  
current into this pin to 1 mA. A typical range of pullup resistor value is 10 kto 100 k.  
When the FB voltage is within the power-good band, +6% above and 6% below the internal reference voltage  
VREF typically, the PGOOD switch is turned off, and the PGOOD voltage is as high as the pulled-up voltage.  
When the FB voltage is outside of the tolerance band, +7% above or 7% below VREF typically, the PGOOD  
switch is turned on, and the PGOOD pin voltage is pulled low to indicate power bad. A glitch filter prevents false  
flag operation for short excursions in the output voltage, such as during line and load transients. The values for  
the various filter and delay times can be found in 7.6. Power-good operation can best be understood by  
reference to 8-9.  
VREF  
107%  
106%  
94%  
93%  
PGOOD  
High  
Low  
8-9. Power-Good Flag  
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8.3.8 Internal Compensation and CFF  
The LMR23630 is internally compensated as shown in 8.2. The internal compensation is designed so that the  
loop response is stable over the entire operating frequency and output voltage range. Depending on the output  
voltage, the compensation loop phase margin can be low with all ceramic capacitors. TI recommends an  
external feed-forward capacitor CFF be placed in parallel with the top resistor divider RFBT for optimum transient  
performance.  
VOUT  
CFF  
RFBT  
FB  
RFBB  
8-10. Feed-forward Capacitor for Loop Compensation  
The feed-forward capacitor CFF in parallel with RFBT places an additional zero before the crossover frequency of  
the control loop to boost phase margin. The zero frequency can be found by:  
1
fZ _ CFF  
=
2pìCFF ìRFBT  
(
)
(7)  
An additional pole is also introduced with CFF at the frequency of:  
1
fP _ CFF  
=
2pìCFF ìRFBT //RFBB  
(
)
(8)  
The zero fZ_CFF adds phase boost at the crossover frequency and improves transient response. The pole fP-CFF  
helps maintaining proper gain margin at frequency beyond the crossover. 9-1 lists the combination of COUT  
,
CFF and RFBT for typical applications, designs with similar COUT but RFBT other than recommended value, adjust  
CFF such that (CFF × RFBT) is unchanged and adjust RFBB such that (RFBT / RFBB) is unchanged.  
Designs with different combinations of output capacitors need different CFF. Different types of capacitors have  
different equivalent series resistance (ESR). Ceramic capacitors have the smallest ESR and need the most CFF.  
Electrolytic capacitors have much larger ESR than ceramic, and the ESR zero frequency location would be low  
enough to boost the phase up around the crossover frequency. Designs that use mostly electrolytic capacitors at  
the output may not need any CFF. The location of this ESR zero frequency can be calculated with Equation 9:  
1
fZ _ESR  
=
2pìC  
ìESR  
(
)
OUT  
(9)  
The CFF creates a time constant with RFBT that couples in the attenuate output voltage ripple to the FB node. If  
the CFF value is too large, it can couple too much ripple to the FB and affect VOUT regulation. Therefore,  
calculate CFF based on output capacitors used in the system. At cold temperatures, the value of CFF might  
change based on the tolerance of the chosen component. This may reduce its impedance and ease noise  
coupling on the FB node. To avoid this, more capacitance can be added to the output or the value of CFF can be  
reduced.  
8.3.9 Bootstrap Voltage (BOOT)  
The LMR23630 provides an integrated bootstrap voltage regulator. A small capacitor between the BOOT and  
SW pins provides the gate drive voltage for the high-side MOSFET. The BOOT capacitor is refreshed when the  
high-side MOSFET is off and the low-side switch conducts. The recommended value of the BOOT capacitor is  
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0.1 μF to 0.47 μF. TI recommends a ceramic capacitor with an X7R or X5R grade dielectric with a voltage  
rating of 16 V or higherfor stable performance over temperature and voltage.  
8.3.10 Overcurrent and Short-Circuit Protection  
The LMR23630 is protected from over-current conditions by cycle-by-cycle current limit on both the peak and  
valley of the inductor current. Hiccup mode will be activated if a fault condition persists to prevent over-heating.  
High-side MOSFET overcurrent protection is implemented by the nature of the peak-current-mode control. The  
HS switch current is sensed when the HS is turned on after a set blanking time. The HS switch current is  
compared to the output of the error amplifier (EA) minus slope compensation every switching cycle. See the 节  
8.2 for more details. The peak current of HS switch is limited by a clamped maximum peak current threshold  
IHS_LIMIT which is constant. Thus, the peak current limit of the high-side switch is not affected by the slope  
compensation and remains constant over the full duty cycle range.  
The current going through LS MOSFET is also sensed and monitored. When the LS switch turns on, the inductor  
current begins to ramp down. The LS switch is not turned OFF at the end of a switching cycle if its current is  
above the LS current limit ILS_LIMIT. The LS switch is kept ON so that inductor current keeps ramping down, until  
the inductor current ramps below the LS current limit ILS_LIMIT. Then the LS switch is turned OFF, and the HS  
switch is turned on after a dead time. This is somewhat different than the more typical peak current limit and  
results in Equation 10 for the maximum load current.  
V
IN - VOUT  
(
)
ì
VOUT  
IOUT _MAX = ILS _LIMIT  
+
2ì fSW ìL  
V
IN  
(10)  
If the current of the LS switch is higher than the LS current limit for 64 consecutive cycles, hiccup current  
protection mode is activated. In hiccup mode, the regulator is shut down and kept off for 5 ms typically before the  
LMR23630 tries to start again. If overcurrent or short-circuit fault condition still exist, hiccup will repeat until the  
fault condition is removed. Hiccup mode reduces power dissipation under severe overcurrent conditions,  
prevents over-heating and potential damage to the device.  
For FPWM version, the inductor current is allowed to go negative. If this current exceed IL_NEG, the LS switch is  
turned off until the next clock cycle. This is used to protect the LS switch from excessive negative current.  
8.3.11 Thermal Shutdown  
The LMR23630 provides an internal thermal shutdown to protect the device when the junction temperature  
exceeds 170°C (typical). The device is turned off when thermal shutdown activates. Once the die temperature  
falls below 155°C (typical), the device reinitiates the power-up sequence controlled by the internal soft-start  
circuitry.  
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8.4 Device Functional Modes  
8.4.1 Shutdown Mode  
The EN pin provides electrical ON and OFF control for the LMR23630. When VEN is below 1 V (typical), the  
device is in shutdown mode. The LMR23630 also employs VIN and VCC UVLO protection. If VIN or VCC voltage  
is below their respective UVLO level, the regulator is turned off.  
8.4.2 Active Mode  
The LMR23630 is in active mode when VEN is above the precision enable threshold, VIN and VCC are above their  
respective UVLO level. The simplest way to enable the LMR23630 is to connect the EN pin to VIN pin. This  
allows self startup when the input voltage is in the operating range 4 V to 36 V. See 8.3.5 and 8.3.4 for  
details on setting these operating levels.  
In active mode, depending on the load current, the LMR23630 is in one of four modes:  
1. Continuous conduction mode (CCM) with fixed switching frequency when load current is above half of the  
peak-to-peak inductor current ripple (for both PFM and FPWM options).  
2. Discontinuous conduction mode (DCM) with fixed switching frequency when load current is lower than half of  
the peak-to-peak inductor current ripple in CCM operation (only for PFM option).  
3. Pulse frequency modulation mode (PFM) when switching frequency is decreased at very light load (only for  
PFM option).  
4. Forced pulse width modulation mode (FPWM) with fixed switching frequency even at light load (only for  
FPWM option).  
8.4.3 CCM Mode  
CCM operation is employed in the LMR23630 when the load current is higher than half of the peak-to-peak  
inductor current. In CCM operation, the frequency of operation is fixed, output voltage ripple is at a minimum in  
this mode, and the maximum output current of 3 A can be supplied by the LMR23630.  
8.4.4 Light Load Operation (PFM Version)  
For PFM version, when the load current is lower than half of the peak-to-peak inductor current in CCM, the  
LMR23630 operates in DCM, also known as diode emulation mode (DEM). In DCM, the LS switch is turned off  
when the inductor current drops to IL_ZC (40 mA typical). Both switching losses and conduction losses are  
reduced in DCM, compared to forced PWM operation at light load.  
At even lighter current loads, PFM is activated to maintain high efficiency operation. When either the minimum  
HS switch ON-time (tON_MIN ) or the minimum peak inductor current IPEAK_MIN (300 mA typ) is reached, the  
switching frequency decreases to maintain regulation. In PFM, switching frequency is decreased by the control  
loop when load current reduces to maintain output voltage regulation. Switching loss is further reduced in PFM  
operation due to less frequent switching actions. The external clock synchronizing is not valid when the  
LMR23630 device enters into PFM mode.  
8.4.5 Light Load Operation (FPWM Version)  
For FPWM version, LMR23630 is locked in PWM mode at full load range. 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 IL_NEG is imposed to prevent damage to the regulators low side FET. When in  
FPWM mode the converter synchronizes to any valid clock signal on the EN/SYNC input.  
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9 Application and Implementation  
备注  
Information in the following applications sections is not part of the TI component specification, and TI  
does not warrant its accuracy or completeness. TIs customers are responsible for determining  
suitability of components for their purposes. Customers should validate and test their design  
implementation to confirm system functionality.  
9.1 Application Information  
The LMR23630 is a step-down DC-to-DC regulator. It is typically used to convert a higher DC voltage to a lower  
DC voltage with a maximum output current of 3 A. The following design procedure can be used to select  
components for the LMR23630. Alternately, the WEBENCH® software may be used to generate complete  
designs. When generating a design, the WEBENCH® software utilizes iterative design procedure and accesses  
comprehensive databases of components. See www.ti.com for more details.  
9.2 Typical Applications  
The LMR23630 only requires a few external components to convert from a wide voltage-range supply to a fixed  
output voltage. 9-1 shows a basic schematic.  
VIN 12 V  
CBOOT  
0.47 F  
BOOT  
VIN  
L
VOUT  
5 V/3 A  
10 H  
CIN  
10 F  
SW  
FB  
RFBT  
88.7 kΩ  
EN/  
SYNC  
PAD  
CFF  
47 pF  
COUT  
100 F  
CVCC  
2.2 F  
VCC  
RFBB  
22.1 kΩ  
PGND  
AGND  
9-1. LM23630 Application Circuit  
The external components must fulfill the needs of the application, but also the stability criteria of the device  
control loop. 9-1 can be used to simplify the output filter component selection.  
9-1. L, COUT, and CFF Typical Values  
fSW (kHz)  
VOUT (V)  
L (µH) (2)  
COUT (µF) (3)  
CFF (pF)  
150  
RFBT (kΩ)(4) (5)  
3.3  
5
15  
300  
200  
100  
47  
51  
88.7  
243  
510  
51  
18  
100  
200  
12  
24  
3.3  
5
33  
See(1)  
See(1)  
75  
33  
6.8  
10  
150  
100  
68  
47  
88.7  
243  
510  
51  
400  
12  
24  
3.3  
5
15  
See(1)  
See(1)  
39  
15  
47  
3.3  
4.7  
2.2  
2.2  
68  
1000  
2200  
47  
25  
88.7  
51  
3.3  
5
47  
33  
33  
18  
88.7  
(1) High ESR COUT gives enough phase boost and CFF not needed.  
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(2) Inductance value is calculated based on VIN = 36 V.  
(3) All the COUT values are after derating. Add more when using ceramic capacitors.  
(4) RFBT = 0 Ωfor VOUT = 1 V. RFBB = 22.1 kΩfor all other VOUT setting.  
(5) For designs with RFBT other than recommended value, please adjust CFF such that (CFF × RFBT) is unchanged and adjust RFBB such  
that (RFBT / RFBB) is unchanged.  
9.2.1 Design Requirements  
Detailed design procedure is described based on a design example. For this design example, use the  
parameters listed in 9-2 as the input parameters.  
9-2. Design Example Parameters  
DESIGN PARAMETER  
EXAMPLE VALUE  
Input voltage, VIN  
12 V typical, range from 8 V to 28 V  
Output voltage, VOUT  
5 V  
3 A  
Maximum output current IO_MAX  
Transient response 0.2 A to 2.5 A  
Output voltage ripple  
5%  
50 mV  
400 mV  
400 kHz  
Input voltage ripple  
Switching frequency fSW  
9.2.2 Detailed Design Procedure  
9.2.2.1 Custom Design With WEBENCH® Tools  
Click here to create a custom design using the LMR23625 device with the WEBENCH® Power Designer.  
1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements.  
2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial.  
3. Compare the generated design with other possible solutions from Texas Instruments.  
The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time  
pricing and component availability.  
In most cases, these actions are available:  
Run electrical simulations to see important waveforms and circuit performance  
Run thermal simulations to understand board thermal performance  
Export customized schematic and layout into popular CAD formats  
Print PDF reports for the design, and share the design with colleagues  
Get more information about WEBENCH tools at www.ti.com/WEBENCH.  
9.2.2.2 Output Voltage Setpoint  
The output voltage of LMR23630 is externally adjustable using a resistor divider network. The divider network is  
comprised of top feedback resistor RFBT and bottom feedback resistor RFBB. Equation 11 is used to determine  
the output voltage:  
VOUT - VREF  
VREF  
RFBT  
=
ìRFBB  
(11)  
Choose the value of RFBB to be 22.1 k. With the desired output voltage set to 5 V and the VREF = 1 V, the RFBB  
value can then be calculated using Equation 11. The formula yields to a value 88.7 k.  
9.2.2.3 Switching Frequency  
The default switching frequency of the LMR23630 is 400 kHz. For other switching frequency, the device must be  
synchronized to an external clock, see 8.3.4 for more details.  
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9.2.2.4 Inductor Selection  
The most critical parameters for the inductor are the inductance, saturation current, and the rated current. The  
inductance is based on the desired peak-to-peak ripple current ΔiL. Because the ripple current increases with  
the input voltage, the maximum input voltage is always used to calculate the minimum inductance LMIN. Use  
Equation 12 to calculate the minimum value of the output inductor. KIND is a coefficient that represents the  
amount of inductor ripple current relative to the maximum output current of the device. A reasonable value of  
KIND should be 20% to 40%. During an instantaneous short or overcurrent operation event, the RMS and peak  
inductor current can be high. The inductor current rating should be higher than the current limit of the device.  
VOUT ì V  
- VOUT  
(
)
IN_MAX  
DiL =  
VIN_MAX ìL ì fSW  
(12)  
(13)  
V
- VOUT  
VOUT  
IN_MAX  
LMIN  
=
ì
IOUT ìKIND  
V
IN_MAX ì fSW  
In general, it is preferable to choose lower inductance in switching power supplies, because it usually  
corresponds to faster transient response, smaller DCR, and reduced size for more compact designs. However,  
inductance that is too low can generate an inductor current ripple that is too high so that overcurrent protection  
at the full load could be falsely triggered. It also generates more conduction loss and inductor core loss. Larger  
inductor current ripple also implies larger output voltage ripple with same output capacitors. With peak current  
mode control, TI does not recommend having an inductor current ripple that is too small. A larger peak-current  
ripple improves the comparator signal-to-noise ratio.  
For this design example, choose KIND = 0.4, the minimum inductor value is calculated to be 8.56 µH. Choose the  
nearest standard 8.2 μH ferrite inductor with a capability of 4-A RMS current and 6-A saturation current.  
9.2.2.5 Output Capacitor Selection  
Choose the output capacitor(s), COUT, with care because it directly affects the steady-state output-voltage ripple,  
loop stability, and the voltage over/undershoot during load-current transients.  
The output ripple is essentially composed of two parts. One is caused by the inductor current ripple going  
through the equivalent series resistance (ESR) of the output capacitors:  
DVOUT_ESR = DiL ìESR = KIND ìIOUT ìESR  
(14)  
The other is caused by the inductor current ripple charging and discharging the output capacitors:  
DiL  
KIND ìIOUT  
DVOUT _C  
=
=
8ì f ìCOUT  
8ì f ìCOUT  
(
)
(
)
SW  
SW  
(15)  
The two components in the voltage ripple are not in phase, so the actual peak-to-peak ripple is smaller than the  
sum of two peaks.  
Output capacitance is usually limited by transient performance specifications if the system requires tight voltage  
regulation with presence of large current steps and fast slew rate. When a fast large load increase happens,  
output capacitors provide the required charge before the inductor current can slew up to the appropriate level.  
The control loop of the regulator usually needs four or more clock cycles to respond to the output voltage droop.  
The output capacitance must be large enough to supply the current difference for four clock cycles to maintain  
the output voltage within the specified range. Equation 17 shows the minimum output capacitance needed for  
specified output undershoot. When a sudden large load decrease happens, the output capacitors absorb energy  
stored in the inductor. which results in an output voltage overshoot. Equation 14 calculates the minimum  
capacitance required to keep the voltage overshoot within a specified range.  
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(16)  
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4ì IOH -IOL  
(
)
COUT  
>
fSW ì VUS  
IO2 H -IO2 L  
COUT  
>
ìL  
2
V
+ VOS - VO2UT  
(
)
OUT  
(17)  
where  
IOL = Low level output current during load transient  
IOH = High level output current during load transient  
VUS = Target output voltage undershoot  
VOS = Target output voltage overshoot  
For this design example, the target output ripple is 50 mV. Presuppose ΔVOUT_ESR = ΔVOUT_C = 50 mV, and  
chose KIND = 0.4. Equation 16 yields ESR no larger than 41.7 mand Equation 17 yields COUT no smaller than  
7.5 μF. For the target over/undershoot range of this design, VUS = VOS = 5% × VOUT = 250 mV. The COUT can  
be calculated to be no smaller than 108 μF and 28.5 μF by Equation 15 and Equation 17, respectively.  
Consider of derating, one 47-μF, 16-V and one 100-μF, 10-V ceramic capacitor with 5-mESR are used in  
parallel.  
9.2.2.6 Feed-Forward Capacitor  
The LMR23630 is internally compensated. Depending on the VOUT and frequency fSW, if the output capacitor  
COUT is dominated by low-ESR (ceramic types) capacitors, it could result in low phase margin. To improve the  
phase boost an external feed-forward capacitor CFF can be added in parallel with RFBT. CFF is chosen such that  
phase margin is boosted at the crossover frequency without CFF. A simple estimation for the crossover  
frequency (fX) without CFF is shown in Equation 18, assuming COUT has very small ESR, and COUT value is after  
derating.  
8.32  
fX  
=
VOUT ìCOUT  
(18)  
Equation 19 for CFF was tested:  
1
CFF  
=
4pì fX ìRFBT  
(19)  
For designs with higher ESR, CFF is not needed when COUT has very high ESR and CFF calculated from  
Equation 19 must reduced with medium ESR. 9-1 can be used as a quick starting point.  
For the application in this design example, a 47-pF, 50-V, COG capacitor is selected.  
9.2.2.7 Input Capacitor Selection  
The LMR23630 device requires high-frequency input decoupling capacitor(s) and a bulk input capacitor,  
depending on the application. The typical recommended value for the high-frequency decoupling capacitor is 4.7  
μF to 10 μF. TI recommends a high-quality ceramic capacitor type X5R or X7R with sufficiency voltage rating.  
To compensate the derating of ceramic capacitors, a voltage rating twice the maximum input voltage is  
recommended. Additionally, some bulk capacitance can be required, especially if the LMR23630 circuit is not  
located within approximately 5 cm from the input voltage source. This capacitor is used to provide damping to  
the voltage spike due to the lead inductance of the cable or the trace. For this design, two 4.7-μF, 50-V, X7R  
ceramic capacitors are used. A 0.1-μF for high-frequency filtering and place it as close as possible to the device  
pins.  
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9.2.2.8 Bootstrap Capacitor Selection  
Every LMR23630 design requires a bootstrap capacitor (CBOOT). TI recommends a capacitor of 0.47 μF, ated  
16 V or higher. The bootstrap capacitor is located between the SW pin and the BOOT pin. The bootstrap  
capacitor must be a high-quality ceramic type with an X7R or X5R grade dielectric for temperature stability.  
9.2.2.9 VCC Capacitor Selection  
The VCC pin is the output of an internal LDO for LMR23630. To insure stability of the device, place a minimum of  
2.2-μF, 16V, X7R capacitor from this pin to ground.  
9.2.2.10 Undervoltage Lockout Setpoint  
The system undervoltage lockout (UVLO) is adjusted using the external voltage divider network of RENT and  
RENB. The UVLO has two thresholds, one for power up when the input voltage is rising and one for power down  
or brown outs when the input voltage is falling. The following equation can be used to determine the VIN UVLO  
level.  
RENT + RENB  
RENB  
V
= VENH ì  
IN_RISING  
(20)  
The EN rising threshold (VENH) for LMR23630 is set to be 1.55 V (typical). Choose the value of RENB to be 287  
kΩ to minimize input current from the supply. If the desired VIN UVLO level is at 6 V, then the value of RENT can  
be calculated using Equation 21:  
V
IN_RISING  
RENT  
=
-1 ìR  
÷
ENB  
÷
VENH  
«
(21)  
Equation 21 yields a value of 820 kΩ. The resulting falling UVLO threshold, equals 4.4 V, can be calculated by  
Equation 22, where EN hysteresis (VEN_HYS) is 0.4 V (typical).  
RENT + RENB  
RENB  
V
= VENH - VEN_HYS  
(
ì
)
IN_FALLING  
(22)  
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9.2.3 Application Curves  
Unless otherwise specified the following conditions apply: VIN = 12 V, fSW = 400 kHz, L = 8.2 µH, COUT = 150 µF, TA = 25 °C.  
VOUT = 5 V  
IOUT = 3 A  
fSW = 400 kHz  
VOUT = 5 V  
IOUT = 150 mA  
fSW = 400 kHz  
fSW = 400 kHz  
IOUT = 2 A  
9-2. CCM Mode  
9-3. DCM Mode  
VOUT = 5 V  
IOUT = 0 mA  
fSW = 400 kHz  
VOUT = 5 V  
IOUT = 0 mA  
9-4. PFM Mode  
9-5. FPWM Mode  
VIN = 12 V  
VOUT = 5 V  
IOUT = 2 A  
VIN = 12 V  
VOUT = 5 V  
9-6. Start Up by VIN  
9-7. Start Up by EN  
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VIN = 12 V  
VOUT = 5 V  
VOUT = 5 V  
IOUT = 3 A  
IOUT = 0.3 A to 3 A, 100 mA / μs  
VIN = 7 V to 36 V, 2 V / μs  
9-8. Load Transient  
9-9. Line Transient  
VOUT = 5 V  
IOUT = 1 A to short  
VOUT = 5 V  
IOUT = short to 1 A  
9-10. Short Protection  
9-11. Short Recovery  
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10 Power Supply Recommendations  
The LMR23630 is designed to operate from an input voltage supply range between 4.5 V and 36 V for the  
HSOIC package and 4 V to 36 V for the WSON package. This input supply must be able to withstand the  
maximum input current and maintain a stable voltage. The resistance of the input supply rail must be low enough  
that an input current transient does not cause a high enough drop at the LMR23630 supply voltage that can  
cause a false UVLO fault triggering and system reset. If the input supply is located more than a few inches from  
the LMR23630, additional bulk capacitance may be required in addition to the ceramic input capacitors. The  
amount of bulk capacitance is not critical, but a 47-μF or 100-μF electrolytic capacitor is a typical choice.  
11 Layout  
11.1 Layout Guidelines  
Layout is a critical portion of good power supply design. The following guidelines will help users design a PCB  
with the best power conversion performance, thermal performance, and minimized generation of unwanted EMI.  
1. The input bypass capacitor CIN must be placed as close as possible to the VIN and PGND pins. Grounding  
for both the input and output capacitors should consist of localized top side planes that connect to the PGND  
pin and PAD.  
2. Place bypass capacitors for VCC close to the VCC pin and ground the bypass capacitor to device ground.  
3. Minimize trace length to the FB pin net. Both feedback resistors, RFBT and RFBB should be located close to  
the FB pin. Place CFF directly in parallel with RFBT. If VOUT accuracy at the load is important, make sure VOUT  
sense is made at the load. Route VOUT sense path away from noisy nodes and preferably through a layer on  
the other side of a shielded layer.  
4. Use ground plane in one of the middle layers as noise shielding and heat dissipation path.  
5. Have a single point ground connection to the plane. The ground connections for the feedback and enable  
components should be routed to the ground plane. This prevents any switched or load currents from flowing  
in the analog ground traces. If not properly handled, poor grounding can result in degraded load regulation or  
erratic output voltage ripple behavior.  
6. Make VIN, VOUT and ground bus connections as wide as possible. This reduces any voltage drops on the  
input or output paths of the converter and maximizes efficiency.  
7. Provide adequate device heat-sinking. Use an array of heat-sinking vias to connect the exposed pad to the  
ground plane on the bottom PCB layer. If the PCB has multiple copper layers, these thermal vias can also be  
connected to inner layer heat-spreading ground planes. Ensure enough copper area is used for heat-sinking  
to keep the junction temperature below 125 °C.  
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11.2 Layout Example  
Output Bypass  
Capacitor  
Output Inductor  
Input Bypass  
Capacitor  
SW  
PGND  
VIN  
BOOT Capacitor  
BOOT  
VCC  
FB  
AGND  
VCC  
Capacitor  
EN/  
SYNC  
UVLO Adjust Resistor  
Output Voltage Set  
Resistor  
Thermal VIA  
VIA (Connect to GND Plane)  
11-1. Sample HSOIC Package Layout  
Output  
Inductor  
Output Bypass  
Capacitor  
PGND  
NC  
SW  
SW  
Input Bypass  
Capacitor  
BOOT  
Capacitor  
BOOT  
VCC  
FB  
VIN  
VIN  
VCC  
Capacitor  
EN/SYNC  
AGND  
UVLO Adjust  
Resistor  
RT  
RT  
Thermal VIA  
VIA (Connect to GND Plane)  
Output Voltage  
Set Resistor  
11-2. Sample WSON Package Layout  
11.3 Compact Layout for EMI Reduction  
Radiated EMI is generated by the high di/dt components in pulsing currents in switching converters. The larger  
area covered by the path of a pulsing current, the more EMI is generated. High frequency ceramic bypass  
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capacitors at the input side provide primary path for the high di/dt components of the pulsing current. Placing  
ceramic bypass capacitor(s) as close as possible to the VIN and PGND pins is the key to EMI reduction.  
The SW pin connecting to the inductor must be as short as possible and just wide enough to carry the load  
current without excessive heating. Use short, thick traces or copper pours (shapes) high current conduction path  
to minimize parasitic resistance. Place the output capacitors close to the VOUT end of the inductor and closely  
grounded to PGND pin and exposed PAD.  
Place the bypass capacitors on VCC as close as possible to the pin and closely grounded to PGND and the  
exposed PAD.  
11.4 Ground Plane and Thermal Considerations  
TI recommends using one of the middle layers as a solid ground plane. Ground plane provides shielding for  
sensitive circuits and traces. It also provides a quiet reference potential for the control circuitry. Connect the  
AGND and PGND pins to the ground plane using vias right next to the bypass capacitors. PGND pin is  
connected to the source of the internal LS switch. They must be connected directly to the grounds of the input  
and output capacitors. The PGND net contains noise at switching frequency and may bounce due to load  
variations. PGND trace, as well as VIN 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 should be used for sensitive routes.  
TI also recommends providing adequate device heat sinking by utilizing the PAD of the device as the primary  
thermal path. Use a minimum 4 by 2 array of 12 mil thermal vias to connect the PAD to the system ground plane  
heat sink. The vias should be evenly distributed under the PAD. Use as much copper as possible, for system  
ground plane, on the top and bottom layers for the best heat dissipation. Use a four-layer board with the copper  
thickness for the four layers, starting from the top of, 2 oz / 1 oz / 1 oz / 2 oz. Four-layer boards with enough  
copper thickness provides low current conduction impedance, proper shielding, and lower thermal resistance.  
The thermal characteristics of the LMR23630 are specified using the parameter RθJA, which characterize the  
junction temperature of silicon to the ambient temperature in a specific system. Although the value of RθJA is  
dependent on many variables, it still can be used to approximate the operating junction temperature of the  
device. To obtain an estimate of the device junction temperature, one may use the following relationship:  
TJ = PD × RθJA + TA  
(23)  
(24)  
PD = VIN × IIN × (1 Efficiency) 1.1 × IOUT 2 × DCR in watt  
where  
TJ = junction temperature in °C  
PD = device power dissipation in watt  
RθJA = junction-to-ambient thermal resistance of the device in °C/W  
TA = ambient temperature in °C  
DCR = inductor DC parasitic resistance in ohm  
The maximum operating junction temperature of the LMR23630 is 125°C. RθJA is highly related to PCB size and  
layout, as well as environmental factors such as heat sinking and air flow.  
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11.5 Feedback Resistors  
To reduce noise sensitivity of the output voltage feedback path, it is important to place the resistor divider and  
CFF close to the FB pin, rather than close to the load. The FB pin is the input to the error amplifier, so it is a high  
impedance node and very sensitive to noise. Placing the resistor divider and CFF closer to the FB pin reduces  
the trace length of FB signal and reduces noise coupling. The output node is a low impedance node, so the trace  
from VOUT to the resistor divider can be long if short path is not available.  
If voltage accuracy at the load is important, make sure voltage sense is made at the load. Doing so corrects for  
voltage drops along the traces and provide the best output accuracy. The voltage sense trace from the load to  
the feedback resistor divider should be routed away from the SW node path and the inductor to avoid  
contaminating the feedback signal with switch noise, while also minimizing the trace length. This is most  
important when high value resistors are used to set the output voltage. TI recommends routing the voltage sense  
trace and place the resistor divider on a different layer than the inductor and SW node path, such that there is a  
ground plane in between the feedback trace and inductor/SW node polygon. This provides further shielding for  
the voltage feedback path from EMI noises.  
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Product Folder Links: LMR23630  
 
LMR23630  
www.ti.com.cn  
ZHCSF93E DECEMBER 2015 REVISED AUGUST 2020  
12 Device and Documentation Support  
12.1 Device Support  
12.1.1 Development Support  
12.1.1.1 Custom Design With WEBENCH® Tools  
Click here to create a custom design using the LMR23625 device with the WEBENCH® Power Designer.  
1. Start by entering the input voltage (VIN), output voltage (VOUT), and output current (IOUT) requirements.  
2. Optimize the design for key parameters such as efficiency, footprint, and cost using the optimizer dial.  
3. Compare the generated design with other possible solutions from Texas Instruments.  
The WEBENCH Power Designer provides a customized schematic along with a list of materials with real-time  
pricing and component availability.  
In most cases, these actions are available:  
Run electrical simulations to see important waveforms and circuit performance  
Run thermal simulations to understand board thermal performance  
Export customized schematic and layout into popular CAD formats  
Print PDF reports for the design, and share the design with colleagues  
Get more information about WEBENCH tools at www.ti.com/WEBENCH.  
12.2 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。  
12.3 支持资源  
TI E2E中文支持论坛是工程师的重要参考资料可直接从专家处获得快速、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。  
12.4 Trademarks  
PowerPADis a trademark of TI.  
TI E2Eis a trademark of Texas Instruments.  
SIMPLE SWITCHER® is a registered trademark of TI.  
WEBENCH® is a registered trademark of Texas Instruments.  
所有商标均为其各自所有者的财产。  
12.5 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。  
12.6 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。  
13 Mechanical, Packaging, and Orderable Information  
The following pages include mechanical, packaging, and orderable information. This information is the most  
current data available for the designated devices. This data is subject to change without notice and revision of  
this document. For browser-based versions of this data sheet, refer to the left-hand navigation.  
Copyright © 2022 Texas Instruments Incorporated  
32  
Submit Document Feedback  
Product Folder Links: LMR23630  
 
 
 
 
 
 
 
 
PACKAGE OPTION ADDENDUM  
www.ti.com  
23-Jun-2023  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
LMR23630ADDA  
LMR23630ADDAR  
LMR23630AFDDA  
LMR23630AFDDAR  
LMR23630APDRRR  
LMR23630APDRRT  
LMR23630DRRR  
LMR23630DRRT  
LMR23630FDRRR  
LMR23630FDRRT  
ACTIVE SO PowerPAD  
ACTIVE SO PowerPAD  
ACTIVE SO PowerPAD  
ACTIVE SO PowerPAD  
DDA  
DDA  
DDA  
DDA  
DRR  
DRR  
DRR  
DRR  
DRR  
DRR  
8
8
75  
RoHS & Green  
NIPDAUAG  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
-40 to 125  
F30A  
F30A  
Samples  
Samples  
Samples  
Samples  
Samples  
Samples  
Samples  
Samples  
Samples  
Samples  
2500 RoHS & Green  
75 RoHS & Green  
NIPDAUAG  
8
NIPDAUAG  
F30AF  
F30AF  
3630P  
3630P  
23630  
23630  
3630F  
3630F  
8
2500 RoHS & Green  
3000 RoHS & Green  
NIPDAUAG  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
ACTIVE  
WSON  
WSON  
WSON  
WSON  
WSON  
WSON  
12  
12  
12  
12  
12  
12  
SN  
SN  
SN  
SN  
SN  
SN  
250  
3000 RoHS & Green  
250 RoHS & Green  
3000 RoHS & Green  
250 RoHS & Green  
RoHS & Green  
(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.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
23-Jun-2023  
(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.  
OTHER QUALIFIED VERSIONS OF LMR23630 :  
Automotive : LMR23630-Q1  
NOTE: Qualified Version Definitions:  
Automotive - Q100 devices qualified for high-reliability automotive applications targeting zero defects  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Jun-2023  
TAPE AND REEL INFORMATION  
REEL DIMENSIONS  
TAPE DIMENSIONS  
K0  
P1  
W
B0  
Reel  
Diameter  
Cavity  
A0  
A0 Dimension designed to accommodate the component width  
B0 Dimension designed to accommodate the component length  
K0 Dimension designed to accommodate the component thickness  
Overall width of the carrier tape  
W
P1 Pitch between successive cavity centers  
Reel Width (W1)  
QUADRANT ASSIGNMENTS FOR PIN 1 ORIENTATION IN TAPE  
Sprocket Holes  
Q1 Q2  
Q3 Q4  
Q1 Q2  
Q3 Q4  
User Direction of Feed  
Pocket Quadrants  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
LMR23630ADDAR  
LMR23630AFDDAR  
SO  
PowerPAD  
DDA  
DDA  
8
8
2500  
2500  
330.0  
12.8  
6.4  
5.2  
2.1  
8.0  
12.0  
Q1  
SO  
330.0  
12.8  
6.4  
5.2  
2.1  
8.0  
12.0  
Q1  
PowerPAD  
LMR23630APDRRR  
LMR23630APDRRT  
LMR23630DRRR  
LMR23630DRRT  
LMR23630FDRRR  
LMR23630FDRRT  
WSON  
WSON  
WSON  
WSON  
WSON  
WSON  
DRR  
DRR  
DRR  
DRR  
DRR  
DRR  
12  
12  
12  
12  
12  
12  
3000  
250  
330.0  
180.0  
330.0  
180.0  
330.0  
180.0  
12.4  
12.4  
12.4  
12.4  
12.4  
12.4  
3.3  
3.3  
3.3  
3.3  
3.3  
3.3  
3.3  
3.3  
3.3  
3.3  
3.3  
3.3  
1.0  
1.0  
1.0  
1.0  
1.0  
1.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
12.0  
12.0  
12.0  
12.0  
12.0  
12.0  
Q2  
Q2  
Q2  
Q2  
Q2  
Q2  
3000  
250  
3000  
250  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Jun-2023  
TAPE AND REEL BOX DIMENSIONS  
Width (mm)  
H
W
L
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
LMR23630ADDAR  
LMR23630AFDDAR  
LMR23630APDRRR  
LMR23630APDRRT  
LMR23630DRRR  
LMR23630DRRT  
SO PowerPAD  
SO PowerPAD  
WSON  
DDA  
DDA  
DRR  
DRR  
DRR  
DRR  
DRR  
DRR  
8
2500  
2500  
3000  
250  
366.0  
366.0  
367.0  
213.0  
367.0  
213.0  
367.0  
213.0  
364.0  
364.0  
367.0  
191.0  
367.0  
191.0  
367.0  
191.0  
50.0  
50.0  
38.0  
35.0  
38.0  
35.0  
38.0  
35.0  
8
12  
12  
12  
12  
12  
12  
WSON  
WSON  
3000  
250  
WSON  
LMR23630FDRRR  
LMR23630FDRRT  
WSON  
3000  
250  
WSON  
Pack Materials-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
23-Jun-2023  
TUBE  
T - Tube  
height  
L - Tube length  
W - Tube  
width  
B - Alignment groove width  
*All dimensions are nominal  
Device  
Package Name Package Type  
Pins  
SPQ  
L (mm)  
W (mm)  
T (µm)  
B (mm)  
LMR23630ADDA  
LMR23630AFDDA  
DDA  
DDA  
HSOIC  
HSOIC  
8
8
75  
75  
517  
517  
7.87  
7.87  
635  
635  
4.25  
4.25  
Pack Materials-Page 3  
PACKAGE OUTLINE  
DRR0012D  
WSON - 0.8 mm max height  
SCALE 4.000  
PLASTIC SMALL OUTLINE - NO LEAD  
3.1  
2.9  
B
A
PIN 1 INDEX AREA  
3.1  
2.9  
0.1 MIN  
(0.05)  
S
C
A
 L
 E
3
0
.
A
SECTION A-A  
TYPICAL  
0.8  
0.7  
C
SEATING PLANE  
0.08 C  
0.05  
0.00  
EXPOSED  
THERMAL PAD  
(0.2) TYP  
1.7 0.1  
6
7
A
A
13  
2X  
2.5  
2.5 0.1  
1
12  
10X 0.5  
0.3  
0.2  
12X  
0.38  
0.28  
12X  
PIN 1 ID  
0.1  
C A B  
C
(OPTIONAL)  
0.05  
4223146/D 10/2018  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. The package thermal pad must be soldered to the printed circuit board for thermal and mechanical performance.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
DRR0012D  
WSON - 0.8 mm max height  
PLASTIC SMALL OUTLINE - NO LEAD  
(1.7)  
12X (0.53)  
SYMM  
1
12  
12X (0.25)  
13  
SYMM  
(2.5)  
10X (0.5)  
(1)  
(R0.05) TYP  
6
7
(0.6)  
(2.87)  
(
0.2) VIA  
TYP  
LAND PATTERN EXAMPLE  
EXPOSED METAL SHOWN  
SCALE:20X  
0.07 MIN  
ALL AROUND  
0.07 MAX  
ALL AROUND  
EXPOSED METAL  
EXPOSED METAL  
SOLDER MASK  
OPENING  
METAL EDGE  
SOLDER MASK  
OPENING  
METAL UNDER  
SOLDER MASK  
NON SOLDER MASK  
DEFINED  
SOLDER MASK  
DEFINED  
(PREFERRED)  
SOLDER MASK DETAILS  
4223146/D 10/2018  
NOTES: (continued)  
4. This package is designed to be soldered to a thermal pad on the board. For more information, see Texas Instruments literature  
number SLUA271 (www.ti.com/lit/slua271).  
5. Vias are optional depending on application, refer to device data sheet. If any vias are implemented, refer to their locations shown  
on this view. It is recommended that vias under paste be filled, plugged or tented.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
DRR0012D  
WSON - 0.8 mm max height  
PLASTIC SMALL OUTLINE - NO LEAD  
SYMM  
(0.47)  
12X (0.53)  
1
12  
12X (0.25)  
METAL  
TYP  
(0.675)  
SYMM  
13  
10X (0.5)  
(1.15)  
(R0.05) TYP  
6
7
(0.74)  
(2.87)  
SOLDER PASTE EXAMPLE  
BASED ON 0.125 mm THICK STENCIL  
EXPOSED PAD  
80.1% PRINTED SOLDER COVERAGE BY AREA  
SCALE:25X  
4223146/D 10/2018  
NOTES: (continued)  
6. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
www.ti.com  
重要声明和免责声明  
TI“按原样提供技术和可靠性数据(包括数据表)、设计资源(包括参考设计)、应用或其他设计建议、网络工具、安全信息和其他资源,  
不保证没有瑕疵且不做出任何明示或暗示的担保,包括但不限于对适销性、某特定用途方面的适用性或不侵犯任何第三方知识产权的暗示担  
保。  
这些资源可供使用 TI 产品进行设计的熟练开发人员使用。您将自行承担以下全部责任:(1) 针对您的应用选择合适的 TI 产品,(2) 设计、验  
证并测试您的应用,(3) 确保您的应用满足相应标准以及任何其他功能安全、信息安全、监管或其他要求。  
这些资源如有变更,恕不另行通知。TI 授权您仅可将这些资源用于研发本资源所述的 TI 产品的应用。严禁对这些资源进行其他复制或展示。  
您无权使用任何其他 TI 知识产权或任何第三方知识产权。您应全额赔偿因在这些资源的使用中对 TI 及其代表造成的任何索赔、损害、成  
本、损失和债务,TI 对此概不负责。  
TI 提供的产品受 TI 的销售条款ti.com 上其他适用条款/TI 产品随附的其他适用条款的约束。TI 提供这些资源并不会扩展或以其他方式更改  
TI 针对 TI 产品发布的适用的担保或担保免责声明。  
TI 反对并拒绝您可能提出的任何其他或不同的条款。IMPORTANT NOTICE  
邮寄地址:Texas Instruments, Post Office Box 655303, Dallas, Texas 75265  
Copyright © 2023,德州仪器 (TI) 公司  

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