New Industry Products

Exar Announces New 4A Peak Current Buck Regulator In 8-Lead Surface Mount Power Package

February 28, 2008 by Jeff Shepard

Exar Corp. announced the latest addition to its PowerBlox™ family of step-down switching regulators with the introduction of the SP7656 3A (4A peak) non-synchronous buck regulator. The new SP7656 is the first in a new series of reduced footprint non-synchronous PowerBlox™ devices, with integration of Type-II compensation.

This regulator is suitable for use in systems deriving power off loosely regulated secondaries from isolated supplies commonly used in industrial systems, as well as intermediate bus voltages used in telecom systems. Other target applications include set top box (PVR/DVR), xDSL CPE equipment, modern digital televisions, and related systems applying power architectures that can benefit greatly from single stage conversions up to 4A peak current. The low output voltage capability also makes this an ideal choice for a highly accurate sub-1V core supply voltage for modern submicron ASIC, DSP and FPGA devices, typically utilizing a 5V or 3.3V system bus as the point of load regulation input bus.

"The SP7656 increases efficiency, extends input voltage range, provides lower output voltage capability, and enhances output accuracy over other monolithic non-synchronous buck regulators on the market today," said Jon Cronk, Applications Director, Power Management. "The SP7656 is architected to provide superior performance for low duty cycle conversion applications from a wide range of input voltages. Size reduction is achieved by reduced package size, integration of loop compensation components, and a high speed 600kHz switching frequency, typically 2x that of comparable devices on the market today."

The SP7656 provides features such as adjustable over current protection, adjustable soft start, under voltage lockout, and 1% set point accuracy. This versatile dc-dc regulator combines operation over a wide input range (4.5 to 29V) with extended low output voltage capability (0.6V), making it suitable as both a 5, 12 or 24V intermediate supply generator and a low voltage point of load power supply. Input feed forward control provides excellent transient response while exceptional regulation accuracy is achieved through a 1% accurate reference.

Exar’s PowerBlox family devices are claimed to provide the industry’s highest buck regulator power density, capable of delivering up to 12A at conversion efficiencies greater than 93% (SP7662) in less than 7 square cm of board space. Devices feature a pin compatible pathway to allow migration to higher current applications with minimal or no PCB layout change requires.

The SP7656 is available in 8-pin SOIC RoHS compliant, lead-free package compatible with JEDEC reflow cycle specifications for lead-free process. Volume pricing starts at $1.85, in 1K unit quantities.