LT1963A Series
1.5A, Low Noise,
Fast Transient Response
LDO Regulators
FEATURES
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
DESCRIPTIO
Optimized for Fast Transient Response
Output Current: 1.5A
Dropout Voltage: 340mV
Low Noise: 40
m
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
< 1mA Quiescent Current in Shutdown
Stable with 10mF Output Capacitor
Stable with Ceramic Capacitors
Reverse Battery Protection
No Reverse Current
Thermal Limiting
APPLICATIO S
■
■
3.3V to 2.5V Logic Power Supplies
Post Regulator for Switching Supplies
The LT
®
1963A series are low dropout regulators opti-
mized 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 < 1mA 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
LT1963A 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 LT1963A
regulators are stable with output capacitors as low as
10mF. Small ceramic capacitors can be used without the
necessary addition of ESR as is common with other
regulators. 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
LT1963A 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)
IN
10µF*
OUT
2.5V
1.5A
10µF*
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
+
LT1963A-2.5
SHDN
SENSE
GND
1963 TA01
*TANTALUM,
CERAMIC OR
ALUMINUM ELECTROLYTIC
U
1963af
U
U
1
LINER [ LINEAR TECHNOLOGY ]
