Texas Instruments LED Drivers LM3553SD

The LM3553SD is a dual flash LED driver capable of delivering up to 1.2A from a single-cell Li-Ion battery. It features a fixed frequency, current mode step-up DC/DC converter with two regulated current sinks, allowing for the driving of high current flash LEDs in both high power Flash mode and lower power Torch mode. The device supports an I2C compatible interface for user-adjustable settings, including 128 current levels and 16 flash safety timer durations. With an input voltage range of 2.7V to 5.5V, the LM3553SD can drive two LEDs in series with 1.2A from a 5V input or 600mA from a 3.0V input. It also includes a low current indicator mode and a fixed output voltage mode. The device is designed with over-voltage protection and a 1.2MHz switching frequency, which allows for the use of smaller, lower-cost output capacitors. The LM3553SD is housed in a compact 3mm x 3mm LLP12 package, making it suitable for applications such as camera phone LED flash and smartphone backlighting.