ON Semi Introduces Charge Pump with Power Saving CABC Mode for Smartphone LED Backlighting

ON Semiconductor has introduced the CAT3649, a 6-channel, high efficiency Quad-Mode® LED driver for use in the latest smartphones and other consumer handheld applications such as digital still cameras and portable media players. The Quad-Mode architecture coupled with Content Adaptive Brightness Control (CABC) ensures market leading efficiency in LED backlighting using only external capacitors.

"With new feature-rich consumer products like smartphones utilizing larger displays, greater demands are being placed upon their batteries to provide longer periods between recharges," said Anthony Russell, Director of LED Power Products at ON Semiconductor. "The powerful combination of high efficiency, PWM (pulse width modulation) dimming, CABC and filtering capabilities make the CAT3649 truly unique within the industry."

Differentiating itself from other devices currently on the market, the highly efficient CAT3649 has a total of four charge pump modes (1, 1.33, 1.5 and 2x), rather than the customary three. The inclusion of a 1.33x mode increases its efficiency by up to 10% compared to traditional charge pump LED drivers using 1.5x operation. This allows the handheld products into which it is incorporated to greatly extend their battery life.

This Quad-Mode fractional charge pump supports a wide range of input voltages, from 2.4 to 5.5V. The LED current can be adjusted by analog dimming in 32 linear increments via the 1-wire interface. Further adjustment can be carried out through PWM. The PWM dimming control is compatible with CABC for PWM signal frequencies from 100 hertz (Hz) to 200 kilohertz (kHz).

The CAT3649 is offered in a compact 3.0 x 3.0mm, Pb-free TQFN-16 package. Pricing for these devices is $0.49 per unit in 100,000 unit quantities.