LM3553 Overview
The LM3553 is a fixed frequency, current mode stepup DC/DC converter with two regulated current sinks. The device is capable of driving loads up to 1.2A from a single-cell Li-Ion battery. The LM3553 includes a TX pin that forces Torch mode during a flash event allowing for synchronization between the RF power amplifier and Flash/Torch modes.
LM3553 Key Features
- 2 Accurate and Programmable LED Current up to 1.2A in 128 Steps
- Total Solution Size < 30mm2
- 90% Peak Efficiency
- Drives 2 LEDs in Series with 1.2A from 5V
- Drives 2 LEDs in Series with 600mA from 3.0V
- Drives 1 LED with 1.2A from 3.0V Input
- Four Operating Modes: Torch, Flash, Indicator
- Programmable Flash Pulse Safety Timer in 16
- TX Input Ensures Synchronization with RF
- LED Disconnect During Shutdown