LT1120A Datasheet

• 20µA Supply Current
• 125mA Output Current
• 2.5V Reference
• Reference Output Sources 4mA and Sinks 4mA
• Open Collector Comparator Sinks 10mA
• Logic Shutdown
• 0.2V Dropout Voltage
• Thermal Limiting
• 8-Lead SO Package

• Battery Systems
• Battery Backup System
• Portable Terminals
• Portable Instruments
• Memory Keep Alive

The LT1120A is a combination micropower positive regulator and free collector comparator on a single monolithic chip. With only 20µA supply current, the LT1120A can supply over 125mA of output current. Input voltage range is from 4.5V to 36V and dropout voltage is 0.6V at 125mA. Dropout voltage decreases with lower load currents.Also included on the chip is a class B output 2.5V reference that can either source or sink current. This allows it to be used as a supply splitter or auxiliary output. A shutdown pin allows logic shutdown of the output.

The comparator can be used for system or battery monitoring. For example, the comparator can be used to warn of low system voltage. Frequency compensation of the comparator for amplifier applications can be obtained by adding external output capacitance.