LT1173 Micropower DC/DC Converter, Adjustable and Fixed 5V, 12V Output.
The LT1173 is a versatile micropower DC‑DC converter that can operate in step‑up, step‑down or inverting modes. It works from 2 V to 30 V supply, delivers fixed 5 V or 12 V outputs, and consumes only 110 µA standby current. Only three external components are required, and the device includes an on‑chip low‑battery detector and programmable current limit.
Typical applications include flash memory VPP generators, LCD bias supplies, battery‑backed circuits, portable instruments, and cellular phones. The converter is offered in 8‑pin MiniDIP or SO‑8 packages, and the fixed‑output versions (LT1173‑5, LT1173‑12) have internal voltage‑setting resistors. Detailed pin functions, electrical characteristics, and design guidelines for inductors, capacitors and diodes are provided.
| Input Voltage (Step‑Up) Range | 2.0 V – 12.6 V |
|---|---|
| Input Voltage (Step‑Down) Max | 30 V |
| Quiescent Current (Switch Off) | 110 µA typical |
| Maximum Switch Current | 1.5 A |
| Oscillator Frequency | 23 kHz typical |
| Duty Cycle (Full Load) | 51 % typical |
The LT1173 consumes only 110 µA supply current at standby.
Only three external components are required.
The LT1173‑5 and LT1173‑12 have on‑chip resistors for fixed 5 V or 12 V outputs.
The device can handle up to 1.5 A of switch current.