Semtech Introduces Miniaturized 10A Synchronous Buck Regulator Platform

Semtech Corp. announced the SC417, the first device in a new family of high current point-of-load voltage regulators, which are described as inherently easy to use without sacrificing electrical performance. Benchmark power density is achieved through advanced packaging, optimized power circuit layout and matching of driver to internal power switches. As the number of power rails in a system grows, driven by increasing bandwidth, content and functionality, a versatile 10A regulator in what approaches chip-scale packaging enables the next generation of complex system loads.

The SC417 has a wide input voltage range of 3 to 28V and achieves high efficiencies over an extended load range. The programmable LDO can be used to provide the 5V necessary for the gate drive bias, allowing the part to operate from a single rail. Internal crossover circuitry bypasses the LDO after startup if the LDO and buck outputs are the same, for optimum efficiency. According to the company, pseudo fixed frequency adaptive on-time control gives the part excellent transient response, reduces the output filter capacitance required and greatly simplifies the design process by removing external compensation components.

Featuring Semtech’s SmartDrive™ technology, which reduces EMI and eliminates snubbing components and gate drive resistors, the SC417 regulator also features what are described as attractive power save functions. Selectable ultrasonic power save allows the device to operate in discontinuous conduction mode at light load conditions, saving quiescent current, while limiting the "floor" frequency to avoid audible noise. The second device in the SC4x7 family, the SC427, with regular power save (no frequency floor) will release next quarter. Semtech’s Smart Power Save™ technique enables these devices to re-enter continuous conduction mode when active loads attempt to pull the output high while in power save mode, pulling the output back down and avoiding over voltage latch-off. Another new feature in the SC417 is its temperature compensated RDS(ON) sensed current limit, which effectively doubles the current limit precision.

"The SC417 10A buck regulator in a 5 x 5mm QFN package breaks new ground with regards to the footprint and profile required for point-of-load power solutions. Able to be used as a module replacement, its flexibility, ease of use and full feature set make it broadly applicable and very attractive to power supply designers," said Alan Burchfield, Product Marketing Manager for Semtech’s Power Management Group. "The wide input operating range permits its use in a broad range of applications including ultra-mobile, industrial and notebook PCs to multi-function printers and digital TV."

The SC417 has built-in soft-start, cycle-by-cycle current limiting, over-temperature, and over- and under- voltage protection features. It also includes a power good output for the switching regulator which may be used for diagnostics and sequencing.

The SC417 is available immediately in production quantities and is priced at $2.58 each in 1,000-piece lots.