Elete launched cellular phone camera LED driver

Elete launched 850kHz, 1x/1.5x/2x high efficiency multi mode charge pump LTC3217, the device used in cellular phone camera applications to drive multiple high current LED. It uses a compact 3mm 3mm QFN package, the use of low noise constant frequency operation mode can be as high as 600mA of the total output current drive up to 4 LED current source. Shutdown mode and current output values can be selected by two logic input pins. The LTC3217 to 4.5V voltage range of the 2.9V is optimized for single Li ion battery input. When the lithium ion battery (nominal value of 3.6V) drive, the efficiency of 92%, to maximize the battery working hours. The device requires only 4 capacitors and two resistors, can be composed of tiny, flat (area < 20mm2, height 0.75mm) solution. LTC3217 charge pump automatic optimization efficiency according to VIN and LED forward voltage. When the device is powered up, it enters the 1x mode and switches to the boost mode (1.5x) when the current voltage source of any LED is working, and then the voltage drop switches the device to the 2x mode. High and low LED current values are programmed by resistors. The brightness is controlled by selecting each of the two input current settings. Brightness can also be controlled by the pulse width modulation of the EN2 pin. Internal circuitry prevents inrush current and excessive input noise during start-up and mode switching. In addition, the device also has an open / short circuit LED protection.

With 16 lead QFN (3mm x 3mm) LTC3217EUD package is available from stock. In 1000 pieces for the bulk purchase, each price starts at $1.70.