New Industry Products

Semtech Enters Digital Power Market with 28V EcoSpeed I2C PWM Controller

June 17, 2010 by Jeff Shepard

Semtech Corp. announced the SC493, the company’s first digitally controlled dc-dc converter. The SC493 is said to address today’s increasingly complex power management requirements by enabling users to digitally configure and interrogate the status of the controller via an I²C bus. The SC493 is the latest addition to Semtech’s EcoSpeed™ converter platform, and it combines the flexibility and feature set of a digital converter with the ultra-fast transient response and high efficiency of Semtech’s patented adaptive on-time (AOT) controller architecture.

"Most controllers today are analog, which can achieve high performance but lack flexibility," said Alan Burchfield, Senior Product Marketing Manager for Semtech’s Power Management Group. "Some controllers now provide digital flexibility, but it is typically achieved via totally digital topologies. This requires the addition of high-speed data converters and power-hungry DSPs. Semtech’s approach takes our best-in-class, adaptive on-time EcoSpeed controller core, and wraps it with a digital interface to provide the benefits of an efficient, high-performance analog core and the flexibility of digital control."

The I²C interface of the SC493 can be used to fine adjust the output voltage and implement margining, as well as to program device functions including output enable/disable, switching frequency, power-on delay time, soft-start time, power-save mode and ultrasonic power-save frequency. The I²C status register bits can be used for diagnostics, including current limit, over temperature, over/under voltage, brown out and power good.

The AOT topology of the SC493 helps designers meet today’s demanding green power requirements by efficiently managing both standby and full current demands. This powerful AOT core, combined with I²C programmability makes the SC493 an optimal choice for high-current, distributed main power supply rails in embedded applications for networking, communications, industrial, and office automation equipment.

Semtech’s AOT core is said to provide the best of conventional current mode, voltage mode and constant on-time control topologies, with minimal tradeoffs. This architecture enables superior static and dynamic regulation and very high efficiency across light to full power loads, while eliminating the need for external compensation components, providing a simple, space-saving and cost-effective power management solution.

The SC493 switching frequency is programmable from 250kHz to 1MHz, which allows power supply rails to be optimized for either conversion efficiency or solution size. The device also incorporates Semtech’s proprietary SmartDrive™ technology, a two-step, high-side FET turn-on technology that reduces EMI in noise-sensitive applications, and provides strong FET gate drives capable of supporting output currents up to 25A.

The EcoSpeed architecture allows the SC493 to work with ceramic input and output capacitors, providing further design flexibility and reliability. This, combined with no external compensation components, optimizes BOM costs and reduces time-to-design. The SC493 is packaged in a low-profile 20-pad, 3.0 x 3.0 x 0.6 mm, lead-free, halogen-free MLPQ package for added space savings.

The SC493 is available immediately in production quantities and is priced at $1.06 each in 3,000-piece lots. Evaluation boards (SC493EVB) are also available.