LT1529
LT1529-3.3/LT1529-5
3A Low Dropout Regulators
with Micropower
Quiescent Current
and Shutdown
DESCRIPTIO
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FEATURES
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Dropout Voltage: 0.6V at IOUT = 3A
Output Current: 3A
Quiescent Current: 50µA
No Protection Diodes Needed
Adjustable Output from 3.8V to 14V
3.3V and 5V Fixed Output Voltages
Controlled Quiescent Current in Dropout
Shutdown IQ = 16µA
Stable with 22µF Output Capacitor
Reverse Battery Protection
No Reverse Current
Thermal Limiting
The LT ®1529/LT1529-3.3/LT1529-5 are 3A low dropout
regulators with micropower quiescent current and shutdown. The devices are capable of supplying 3A of output
current with a dropout voltage of 0.6V. Designed for use
in battery-powered systems, the low quiescent current,
50µA operating and 16µA in shutdown, make them an
ideal choice. The quiescent current is well controlled; it
does not rise in dropout as it does with many other low
dropout PNP regulators.
Other features of the LT1529 /LT1529-3.3/LT1529-5 include the ability to operate with small output capacitors.
They are stable with 22µF on the output while most older
devices require up to 100µF for stability. Small ceramic
capacitors can be used, enhancing manufacturabiltiy.
Also the input may be connected to voltages lower than the
output voltage, including negative voltages, without reverse current flow from output to input. This makes the
LT1529/LT1529-3.3/LT1529-5 ideal for backup power
situations where the output is held high and the input is at
ground or reversed. Under these conditions, only 16µA
will flow from the OUTPUT pin to ground. The devices are
available in 5-lead TO-220 and 5-lead DD packages.
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APPLICATIO S
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High Efficiency Regulator
Regulator for Battery-Powered Systems
Post Regulator for Switching Supplies
5V to 3.3V Logic Regulator
, LTC and LT are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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TYPICAL APPLICATIO
Dropout Voltage
0.6
5V Supply with Shutdown
VIN > 5.5V
VIN
OUTPUT
1
+
LT1529-5
4
SHDN SENSE
5V
3A
2
22µF
GND
3
VSHDN (PIN 4)
< 0.25
> 2.8
NC
OUTPUT
OFF
ON
ON
DROPOUT VOLTAGE (V)
0.5
5
0.4
0.3
0.2
0.1
LT1529 • TA01
0
0
0.5
1.0
1.5
2.0
OUTPUT CURRENT (A)
2.5
3.0
LT1529 • TA02
152935fb
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