The LM2754 is an integrated low noise, high current switched capacitor DC/DC converter with four regulated current sinks. The device is optimized for driving 1 to 4 high power white LEDs in parallel with a maximum current of 800mA. Maximum efficiency is achieved over the input voltage range by actively selecting the proper gain based on the LED forward voltage and current requirements. Two external low power resistors set the desired current for Torch and Flash modes. The TX pin allows the device to be forced into Torch mode during a Flash pulse, allowing for synchronization between the RF power amplifier pulse and Flash/Torch modes. To protect the device and Flash LEDs, internal Time-Out circuitry turns off the LM2754 in case of a faulty prolonged Flash mode. Internal soft-start circuitry limits the amount of inrush current during start-up. The LM2754 is available in a small 24-pin thermally enhanced LLP package.
The LM2754 is an adaptive 1×/1.5×/2× CMOS charge‑pump LED driver designed for camera flash and torch applications. It provides four constant‑current sinks, each capable of 200 mA in flash mode and 100 mA in torch mode, with a total output current up to 800 mA.
The device includes internal soft‑start, current‑limit, flash‑timeout, and thermal‑shutdown circuitry, and is offered in a 24‑pin leadless leadframe (LLP‑24) package measuring 4 mm × 4 mm × 0.8 mm. Detailed electrical characteristics, pin descriptions, and layout recommendations are provided for PCB designers.
| Maximum Output Current | 800 mA |
|---|---|
| Input Voltage Range | 2.8 V to 5.5 V |
| Package Size | 4 mm × 4 mm × 0.8 mm |
| Junction Temperature Range | -40 °C to +125 °C |
| Thermal Shutdown Temperature | 150 °C (typ.) |
The LM2754 can sink up to 800 mA total, with each of the four current sinks capable of 200 mA in flash mode.
A built‑in timeout circuit disables the flash current sinks after 1 second of continuous flash mode.
The device is supplied in a 24‑pin leadless leadframe (LLP‑24) package measuring 4 mm × 4 mm × 0.8 mm.