Ballast device evens out LED brightness

Edited by the Electronicstalk editorial team Apr 23, 2007

LED ballast device drives three separate strings of LEDs with 3% accurate current matching, delivering uniform LED brightness.

The LT3003 from Linear Technology is an LED ballast device that drives three separate strings of LEDs with 3% accurate current matching, delivering uniform LED brightness.

The LT3003 is capable of driving up to 24 LEDs at 350mA each, three strings of eight LEDs each, making it ideal for backlighting a wide variety of TFT-LCDs and head-up display applications.

The LT3003 operates in boost mode, buck mode and buck-boost mode, enabling operation in many LED applications.

Its wide input voltage range of 3 to 40V makes it versatile for most LED applications.

True colour PWM dimming enables dimming ratios of up to 3000:1 with a logic level signal at the PWM pin for all modes without the need of external level shifting circuitry.

Packaged in an MSOP-10, the LT3003 offers a very compact, high accuracy LED ballasting solution.

The LT3003's LED ballasting design is superior to conventional methods of running three separate channels with external ballast resistors which require expensive factory calibration.

For applications with an input supply that varies above and below the output voltage of the LED strings, the LT3003 allows the LEDs to be returned to the input supply (buck-boost mode) instead of being limited to only sepic solutions.

The LT3003 is ideal for use in designs with Linear Technology's LT1618, LT3474, LT3475, LT3476, LT3477 and LTC3783 LED drivers.

The LT3003EMSE is available from stock in a 10-lead thermally enhanced MSOP-10 package.

1000-piece pricing starts at US $1.16 each.