Texas Instruments LMR12010 SIMPLE SWITCHER® 20Vin, 1A Step-Down Regulator in SOT-23 Demo Board LMR12010YMKDEMO/NOPB LMR12010YMKDEMO/NOPB 数据表
产品代码
LMR12010YMKDEMO/NOPB
User's Guide
SNVA490A – September 2011 – Revised April 2013
AN-2164 LMR12010 Demo Board
1
Introduction
The LMR12010 is a step down DC-DC regulator that operates at the following switching frequencies: the
LMR12010X at 1.6MHz and the LMR12010Y at 3MHz. The demo board is configured to convert 5V input
to 1.8V output at 1A load current using the Y version. The tiny low profile thin SOT23 package allows the
design to use less than 1 square inch of board area.
LMR12010X at 1.6MHz and the LMR12010Y at 3MHz. The demo board is configured to convert 5V input
to 1.8V output at 1A load current using the Y version. The tiny low profile thin SOT23 package allows the
design to use less than 1 square inch of board area.
The circuit is configured with the boost diode connected to V
IN
. V
IN
must not exceed the maximum
operating limit of 5.5V + V
fD2
using this configuration. This ensures that the voltage between the Boost and
SW pins, V
BOOST
- V
SW
, does not exceed 5.5V for proper operation. For more information regarding this
requirement, see the LMR12010 SIMPLE SWITCHER® 20Vin, 1A Step-Down Voltage Regulator in SOT-
23 Data Sheet (
23 Data Sheet (
The schematics at the end of this document show how to reconfigure this demo board for various input
and output conditions as discussed in the LMR12010 SIMPLE SWITCHER® 20Vin, 1A Step-Down
Voltage Regulator in SOT-23 Data Sheet (
and output conditions as discussed in the LMR12010 SIMPLE SWITCHER® 20Vin, 1A Step-Down
Voltage Regulator in SOT-23 Data Sheet (
). Short or leave open the connections as indicated in
the schematics. The above restrictions for the input voltage are valid only for the demo board as shipped
with the demo board schematic shown in
with the demo board schematic shown in
2
Features
•
3.0V to 5V Input Voltage Range (as shipped)
•
1.8V Output Voltage
•
Up to 1A Output Current
•
Switching Frequency of 3MHz
•
Small Solution Size (17mm x 17mm)
3
Enable Operation
The demo board includes a spot for a pull-up resistor R5 (not stuffed) to enable the device once V
IN
has
exceeded 1.8V (typ). A typical value for this resistor is 100K
Ω
. Otherwise use the EN post to apply a logic
signal to test startup and shutdown of the device. Never allow the EN voltage to exceed V
IN
.
4
Adjusting the Output Voltage
The output voltage can be changed from 1.8V to another voltage by adjusting the feedback resistors using
:
V
OUT
= V
FB
(1+(RFBT/RFBB))
(1)
Where V
FB
is 0.8V.
For more information on component selection and features, see the device-specific data sheet.
All trademarks are the property of their respective owners.
1
SNVA490A – September 2011 – Revised April 2013
AN-2164 LMR12010 Demo Board
Copyright © 2011–2013, Texas Instruments Incorporated