Date: 28/09/2010

LED Driver from National can drive current to two independently dimmable strings of LEDs

National Semiconductor has released the LM3492 LED driver with dynamic headroom control that drives current to two independently dimmable strings of LEDs strings with a maximum power of 15W and an output voltage of up to 65V. The LM3492 is a member of National's PowerWise energy-efficient product family and is suggested for automotive LCD backlight applications. Integrated fast slew rate current regulators allow high frequency and narrow pulse width dimming signals to achieve a very high contrast ratio of 1000:1. The LED current is programmable from 50 mA to 200 mA by a single resistor. To maximize the efficiency, dynamic headroom control (DHC) automatically adjusts the LED driving voltage to a minimum level.

The LM3492's dynamic headroom control feature adjusts the LED supply voltage through the boost converter feedback . Three embedded MOSFETs are used to reduce system complexity and cost.

The LM3492 includes a versatile COMM pin which serves as a bi-directional input/output pin interfacing with an external MCU for command and diagnostic functions.

Package: 20-pin thermally enhanced TSSOP

Availability: Now