LTC3452 technology can drive 5 parallel white LED, current up to 25mA

Linear Technology Corporation (Linear Technology Corporation) the day before the launch of the synchronous buck boost DC/DC converter LTC3452, the device is optimized using single lithium-ion battery to drive the two groups of white LED. LTC3452 can drive up to 5 parallel LED, and each LED drive current up to 25mA, can provide backlight for LCD display.

According to the linear introduction, the device also can drive two LED, and the drive current of each LED up to 200mA (or a LED drive current 400mA) for camera flash applications. LTC3452's synchronous buck boost topology provides maximum efficiency of up to 90% in the 2.7V to 4.2V range of available Li ion battery voltage, maximizing battery operating time. 4mm x 4mmQFN package and constant 1MHz switching frequency ensure the realization of most handheld applications required for very compact solutions for the board area.

Depending on the input voltage and the maximum forward voltage drop of the LED, the LTC3452 can operate in synchronous buck, synchronous boost or buck boost mode. The best efficiency is obtained by detecting which LED requires the highest forward voltage drop on the programmed current and adjusting the common output rail to achieve a minimum differential pressure. The maximum LED current per display can be programmed with a single external resistor. The dual enable pin allows PWM brightness control on the TFT display, while a separate on / off control pin is used for the flash output. Other features include internal soft start, open / short circuit LED protection and over temperature protection.

4mm * 4mmDFN package with LTC3452EUF spot supply. In 1000 pieces for the bulk purchase, each price starts at $1.80.