New Industry Products

Semtech Releases DC-DC Converter Platform To Extend Battery Life In Portable Devices

January 10, 2008 by Jeff Shepard

Semtech Corp. announced the SC198 and SC198A, two new dual-output synchronous dc-dc buck converters each with eight VID programmable output voltage settings that allow portable systems manufacturers to easily lower processor voltages and extend the battery life of their devices. The SC198 and SC198A are said to provide flexible and cost-effective options for powering core ICs in fixed 5V, single Li-ion cell portable systems or 3-cell NiMH/NiCd systems such as mobile/cordless phones, MP3 players and handheld game consoles.

The SC198 and SC198A operate with an input voltage range of 2.7 to 5.5V. The output voltage for the devices can be digitally programmed via control pins to eight different output pairs, ranging from 1.0 to 3.3V. This capability allows system designers to dynamically change the output voltage without the need for four programming resistors that would be otherwise required. Each of the two outputs from the SC198A is capable of supplying 800mA of current while the SC198 sources up to 600mA per converter.

Each channel from either converter operates with a fixed 1MHz oscillator frequency, which maximizes the efficiency under normal loads. Under light loads, the regulators automatically transition to power save (PSAVE) mode to maintain high efficiency.

The oscillators on both channels operate 180° out-of-phase with each other to minimize the input ripple current. Both devices can be forced to fixed pulse-width modulation (PWM) mode to further reduce noise for sensitive applications. Device quiescent current in shutdown is less than 1µA.

The regulators offer short-circuit and thermal protection on the output to safeguard the devices under extreme operating conditions. The SC198 and SC198A are both offered in thermally enhanced, RoHS and WEEE compliant 4 x 4 mm MLPQ-20 packages.

"We’ve combined the Semtech legacy of feature-rich converters with new integration and miniaturization capabilities to deliver compact and easy-to-use converters. VID output control as well as the integration of output voltage setting resistors and compensation components reduces both component selection and design time," said Julius Sarkis, Semtech Product Marketing Manager, Power Management.

The SC198 and SC198A are both available immediately in production quantities and are both priced at $0.98 each in 1,000-piece lots.