LT1963 Series
1.5A, Low Noise,
Fast Transient Response
LDO Regulators
FEATURES
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DESCRIPTIO
Optimized for Fast Transient Response
Output Current: 1.5A
Dropout Voltage: 340mV
Low Noise: 40
µ
V
RMS
(10Hz to 100kHz)
1mA Quiescent Current
No Protection Diodes Needed
Controlled Quiescent Current in Dropout
Fixed Output Voltages: 1.5V, 1.8V, 2.5V, 3.3V
Adjustable Output from 1.21V to 20V
< 1µA Quiescent Current in Shutdown
Stable with 10µF Output Capacitor
Reverse Battery Protection
No Reverse Current
Thermal Limiting
APPLICATIO S
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3.3V to 2.5V Logic Power Supplies
Post Regulator for Switching Supplies
The LT
®
1963 series are low dropout regulators optimized
for fast transient response. The devices are capable of
supplying 1.5A of output current with a dropout voltage of
340mV. Operating quiescent current is 1mA, dropping to
< 1µA in shutdown. Quiescent current is well controlled; it
does not rise in dropout as it does with many other
regulators. In addition to fast transient response, the
LT1963 regulators have very low output noise which
makes them ideal for sensitive RF supply applications.
Output voltage range is from 1.21V to 20V. The LT1963
regulators are stable with output capacitors as low as
10µF. Internal protection circuitry includes reverse battery
protection, current limiting, thermal limiting and reverse
current protection. The devices are available in fixed
output voltages of 1.5V, 1.8V, 2.5V, 3.3V and as an
adjustable device with a 1.21V reference voltage. The
LT1963 regulators are available in 5-lead TO-220, DD,
3-lead SOT-223 and 8-lead SO packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATION
Dropout Voltage
400
3.3V to 2.5V Regulator
DROPOUT VOLTAGE (mV)
350
300
250
200
150
100
50
0
0
0.2
0.4 0.6 0.8 1.0 1.2
OUTPUT CURRENT (A)
1.4 1.6
1963 TA02
+
V
IN
> 3V
10µF
IN
OUT
LT1963-2.5
+
10µF
2.5V
1.5A
SHDN
SENSE
GND
1963 TA01
U
1963fa
U
U
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