POWER MANAGEMENT
Description
The LP2951A is an improved version of the LP2951 and
features tighter tolerance on the output voltage and
reference voltage specifications. Both the LP2951 and
LP2951A feature 150mA output current capability.
The LP2951 series of low power voltage regulators have
low quiescent current and low dropout voltage. The
quiescent current increases minimally during dropout
conditions thereby extending battery life.
Available in the 8 lead SOIC package, the LP2951 series
includes features such as shutdown and low output
voltage detect (typically due to low battery conditions).
This function may also be used as a power on reset
function when triggered by CMOS or TTL inputs.
The circuit can be used as a fixed voltage 5 volt regulator
or adjusted between 1.24 volts and 29 volts using
external resistor pairs.
150mA Adjustable
Voltage Regulator
Features
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Guaranteed 150mA current
Adjustable output voltage - 1.24V to 29V
Accurate 5V output @ 150mA
Low dropout voltage - 350 to 400mV @ 150mA
Regulator or reference functions
Direct replacement for LP2951AC, MIC2951-02,
AS2951AC
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Full industrial temperature range
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SO-8 package
LP2951A
Applications
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Microcontroller supplies
Linear regulators
Adjustable Supplies
Switching power supplies - post-regulation
Portable modems
Battery powered systems
Cellular telephones
Voltage references
Typical Application Circuits
C1
10nF
R1
V
OUT
=
V
REF
1
+
R2
R1
U1
VOUT = 1.24V to 30V
1
2
SHUTDOWN INPUT
3
4
+
C2
3.3uF
OUT
LP2951A
IN
FB
TAP
ERRORB
8
7
6
5
ERROR OUTPUT
R2
VIN
SENSE
SHDN
GND
R3
100k
Revision 1, January 2001
1
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