White LED driver includes programmable oscillator frequency

National Semiconductor Corp. has launched an inductive-boost series white LED driver that features programmable oscillator frequency. With a 2.3V to 7V input voltage range, the new LM2707 driver is suitable for display backlighting and other general-purpose lighting applications that use single-cell Lithium-ion batteries.

When stacking the LEDs in series between the output and the low-voltage feedback pin, the LM2707 provides tightly regulated LED currents, exceptional LED brightness uniformity and very high LED-drive power efficiency of greater than 80 percent, explained the company. LED drive capability include 3 LEDs at 30mA, 4 LEDs at 20mA, and 6 LEDs (2 strings of 3) at 15mA.

Additional features include an LED drive efficiency of >80 percent, high-speed PWM brightness control capability, over-voltage protection (18V min, 19V typical, 20V max), and inrush and inductor current limiting. Additionally, National said, the new LED driver does not need external compensation.

Housed in a SOT23-8 package, the LM2707 is priced at 76 cents in quantities of 1,000.