LT1761 Series
100mA, Low Noise,
LDO Micropower
Regulators in SOT-23
U
FEATURES
DESCRIPTIO
The LT®1761 series are micropower, low noise, low
dropout regulators. With an external 0.01μF bypass
capacitor, output noise drops to 20μVRMS over a 10Hz to
100kHz bandwidth. Designed for use in battery-powered
systems, the low 20μA quiescent current makes them an
ideal choice. In shutdown, quiescent current drops to less
than 0.1μA. The devices are capable of operating over an
input voltage from 1.8V to 20V, and can supply 100mA of
output current with a dropout voltage of 300mV. Quies-
cent current is well controlled, not rising in dropout as it
does with many other regulators.
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Low Noise: 20μVRMS (10Hz to 100kHz)
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Low Quiescent Current: 20μA
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Wide Input Voltage Range: 1.8V to 20V
Output Current: 100mA
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Very Low Shutdown Current: < 0.1μA
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Low Dropout Voltage: 300mV at 100mA
Fixed Output Voltages: 1.2V, 1.5V, 1.8V, 2V, 2.5V,
2.8V, 3V, 3.3V, 5V
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Adjustable Output from 1.22V to 20V
Stable with 1μF Output Capacitor
Stable with Aluminum, Tantalum or
Ceramic Capacitors
The LT1761 regulators are stable with output capacitors
as low as 1μF. Small ceramic capacitors can be used
without the series resistance required by other regulators.
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Reverse Battery Protected
No Reverse Current
No Protection Diodes Needed
Overcurrent and Overtemperature Protected
Available in TinyU5-Lead SOT-23 Package
Internal protection circuitry includes reverse battery pro-
tection, current limiting, thermal limiting and reverse
current protection. The device is available in fixed output
voltages of 1.2V, 1.5V, 1.8V, 2V, 2.5V, 2.8V, 3V, 3.3V and
5V, and as an adjustable device with a 1.22V reference
voltage. The LT1761 regulators are available in the 5-lead
SOT-23 package.
APPLICATIO S
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Cellular Phones
Pagers
Battery-Powered Systems
Frequency Synthesizers
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, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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Wireless Modems
U
TYPICAL APPLICATIO
10Hz to 100kHz Output Noise
5V Low Noise Regulator
5V AT100mA
20μV NOISE
10μF
IN
OUT
BYP
V
RMS
IN
+
5.4V TO
20V
1μF
0.01μF
V
LT1761-5
OUT
20μV
RMS
100μV/DIV
SHDN
GND
1761 TA01
1761 G48
1761sfc
1