Frugal LED driver saves components too

Edited by the Electronicstalk editorial team Oct 10, 2001

The SC600 LED driver incorporates Semtech's new mAhXLife (milliamp hours extended life) technology to produce a highly efficient, tightly regulated, output voltage to power LED backlighting.

The SC600 LED driver incorporates Semtech's new mAhXLife (milliamp hours extended life) technology to produce a highly efficient, tightly regulated, output voltage to power LED backlighting in colour LCD displays.

The inductorless design uses only four external 1uF ceramic capacitors to provide a reduced-EMI solution in a small, low profile MSOP-10 package.

The SC600 can support applications that require up to 120mA of output current with input voltages ranging between 2.85 to 6.5V.

Three preset output voltages of 4.0, 4.5 or 5.0V are offered to accommodate the varying forward voltage requirements of blue and white LED or RGB LED arrays used for portable backlighting.

"Portable equipment demands higher feature integration, yet requires higher power conservation", said Eddie Yeow, director of the portable power management product line at Semtech.

"Current designs employ more costly, high profile inductors and, thereby, increase system complexity and footprint size.

With the new SC600, we addressed these concerns and created a highly dense, more power efficient solution that can power up to six LEDs in a parallel configuration".

Designed for use in cellular phones, PDAs, handheld computers, portable electronics, wireless web appliances, electronic books and similar products, the SC600 LED driver has a peak efficiency of over 95% to extend battery life while conserving board real estate.

Selectable switching frequencies (from 8 to 650kHz) maximise efficiencies with respect to load for optimised power management.

?Short circuit and overtemperature controls ensure components are protected, and low input/output ripple reduces system noise and filter components.

The SC600 is currently available in MSOP-10 packaging, with prices beginning at $1.40 in production quantities of 1000 pieces.