Datasheet LT1120 (Analog Devices)

LT1120 Micropower Regulator with Comparator and Shutdown
U FEATURES DESCRIPTIO
■ 40μA Supply Current The LT®1120 is a combination micropower positive regu- ■ 125mA Output Current lator and free collector comparator on a single monolithic ■ 2.5V Reference Voltage chip. With only 40μA supply current, the LT1120 can ■ Reference Output Sources 2mA and Sinks 2mA supply over 125mA of output current. Input voltage range ■ Open Collector Comparator Sinks 10mA is from 4.5V to 36V and dropout voltage is 0.6V at 125mA. ■ Logic Shutdown Dropout voltage decreases with lower load currents. Also ■ 0.2V Dropout Voltage included on the chip is a class B output 2.5V reference that ■ Thermal Limiting can either source or sink current. A shutdown pin allows ■ Available in 8-Lead DIP and SO Packages logic shutdown of the output.
U
The comparator can be used for system or battery moni-
APPLICATIO S
toring. For example, the comparator can be used to warn of low system voltage. Frequency compensation of the ■ Battery Systems comparator for amplifier applications can be obtained by ■ Battery-Backup System adding external output capacitance. ■ Portable Terminals ■ Portable Instruments The 2.5V reference will source or sink current. This allows ■ Memory Keep-Alive it to be used as a supply splitter or auxiliary output. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.
U TYPICAL APPLICATIO Dropout Voltage and Supply Current
1.00 10
5V Regulator
SUPPLY CURRENT (mA) V 5 4 IN > 5.2V VIN VOUT 5V IQ = 40μA LT1120 0.001μF 1M 0.10 1 + + 2 10μF FB 25μF SHDN GND 1M DROPOUT VOLTAGE (V) 3 1 SHUTDOWN 1120 TA01 0.01 0.1 0.1 1 10 100 1000 OUTPUT CURRENT (mA) 1120 TA02 1120fd 1