Final Electrical Specifications
LT1962 Series
300mA, Low Noise,
Micropower
LDO Regulators
April 2000
FEATURES
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DESCRIPTIO
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Low Noise: 20µV
RMS
(10Hz to 100kHz)
Output Current: 300mA
Low Quiescent Current: 30µA
Wide Input Voltage Range: 1.8V to 20V
Low Dropout Voltage: 270mV
Very Low Shutdown Current: < 1
µ
A
No Protection Diodes Needed
Fixed Output Voltages: 2.5V, 3V, 3.3V, 5V
Adjustable Output from 1.22V to 20V
Stable with 3.3µF Output Capacitor
Stable with Aluminum, Tantalum or
Ceramic
Capacitors
Reverse Battery Protection
No Reverse Current
Overcurrent and Overtemperature Protected
8-Lead MSOP Package
APPLICATIO S
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Cellular Phones
Battery-Powered Systems
Noise-Sensitive Instrumentation Systems
The LT
®
1962 series are micropower, low noise, low
dropout regulators. The devices are capable of supplying
300mA of output current with a dropout voltage of 300mV.
Designed for use in battery-powered systems, the low
30µA quiescent current makes them an ideal choice.
Quiescent current is well controlled; it does not rise in
dropout as it does with many other regulators.
A key feature of the LT1962 regulators is low output noise.
With the addition of an external 0.01µF bypass capacitor,
output noise drops to 20µV
RMS
over a 10Hz to 100kHz
bandwidth. The LT1962 regulators are stable with output
capacitors as low as 3.3µF. Small ceramic capacitors can
be used without the series resistance required by other
regulators.
Internal protection circuitry includes reverse battery pro-
tection, current limiting, thermal limiting and reverse
current protection. The parts come in fixed output volt-
ages of 2.5V, 3V, 3.3V and 5V, and as an adjustable device
with a 1.22V reference voltage. The LT1962 regulators are
available in the 8-lead MSOP package.
, LTC and LT are registered trademarks of Linear Technology Corporation.
TYPICAL APPLICATIO
400
3.3V Low Noise Regulator
DROPOUT VOLTAGE (mV)
V
IN
3.7V TO
20V
IN
1µF
OUT
SENSE
LT1962-3.3
SHDN
GND
BYP
1962 TA01
350
3.3V AT 300mA
20µV
RMS
NOISE
10µF
300
250
200
150
100
50
0
0
50
100
150
200
LOAD CURRENT (mA)
250
300
+
0.01µF
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
U
Dropout Voltage
1962 TA02
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1