New Industry Products

Vishay Debuts Three New Little Foot Plus Devices

February 27, 2001 by Jeff Shepard

Vishay Siliconix (Santa Clara, CA) has three new Little Foot Plus devices, each of which combines a low-side synchronous MOSFET, a high-side control MOSFET, and a Schottky diode in a single SO-8 package. The company reports that the new devices allow designers to replace three discrete devices with a single integrated solution. Optimized for synchronous buck converters with a switching frequency of up to 300kHz, the three devices combine a 30V breakdown voltage with power MOSFET on-resistance of 22 milliohms per channel at a 10V gate drive. Each MOSFET can handle up to 7.5A.

Maximum forward voltage for the Schottky diode component is 0.5V at 1A. Source and gate pins reduce control-loop inductance for improved gate drive. Each device provides a different pinout variation. The Si4808DY provides a dual pinout with the Schottky diode in the lower position, while the Si4834DY provides a dual pinout with the Schottky diode in the upper position. In the Si4830DY, the upper MOSFET and the Schottky are connected internally, eliminating the need for an external connection on the pc board. Typical end applications for the devices include notebook computers, game stations and other space-sensitive information appliances.

"These new Little Foot Plus devices simplify the designer's task by componentizing a 1V buck dc-to-dc converter," said Matthew Carter, product marketing manager at Vishay Siliconix. "In addition to saving space and reducing component count, by reducing three packages to one we've eliminated the interpackage parasitics associated with discrete solutions."

Samples and production quantities of all three devices are available now, with lead times of eight to 10 weeks for larger orders. Pricing in 100,000-piece quantities starts at $0.59.