New Industry Products

ON Semi Launches 6W LED Driver With Integrated DC-DC Boost Converter For Larger LCD Panel Backlighting

February 26, 2009 by Jeff Shepard

ON Semiconductor has introduced a new 6W LED driver with an integrated, high-power dc-dc boost converter and on-chip diagnostics to maximize efficiency in larger, general purpose LCD panel backlighting applications.

As the company’s first multi-channel boost device, the CAT4106 is capable of driving as many as 40 white LEDs – or four strings of 10 LEDs with up to 36V per string – for a total of 6W of LED output power. Additionally, the device enables designers to maximize backlighting efficiency and reduce space via its built-in diagnostics functions, which automatically adjust the output voltage to drive the highest forward voltage (Vf) string with the minimum head room voltage.

The on-chip diagnostic circuit allows designers to set the minimum and maximum voltage limits for the acceptable range of operation for LED strings through external programming resistors. Any channel which does not regulate within the set range of Open Circuit or Short Circuit LED will be detected and flagged on the FAULT logic output (active-low, open-drain). The device also provides thermal shutdown and overvoltage protection (OVP).

The CAT4106 features low dropout LED channels of 500mV at 175mA and a high-frequency pulse width modulation (PWM) interface, which supports multiple frequencies up to 2 kilohertz (kHz), providing precise, high-resolution dimming control while the device remains fully biased.

Key features include: four matched output LED channels; integrated dc-dc boost converter; up to 6W LED total output power; low dropout LED channels, 500mV at 175mA; high-frequency PWM interface, up to 2 kHz; and on-chip diagnostics with adjustable Short/Open LED detection.

The CAT4106 LED driver is available in a 4 x 4mm 16-lead TQFN package and a 16-lead TSSOP package with an exposed thermal pad for enhanced power dissipation for $1.06 USD per unit in 10,000 unit quantities. Samples and evaluation boards are available now. Projected lead-time for production quantities is currently 6 to 8 weeks ARO.