FET Chipset Optimized For DC/DC Circuits

Consisting of devices that are individually optimized for switching and synchronous rectification functions, this MOSFET chipset consists of the Si4874DY, a 7.5 milliohm device with 35-nC gate charge, and the Si4884DY, a 10.5 ohm device with 15.3-nC gate charge. The Si4874DY provides the low on-resistance required for the bottom freewheeling MOSFET that carries the current for the majority of the time, and is designed to withstand fast switching transients. For the upper MOSFET in the same circuit, the Si4884DY provides the fast switching times that are critical for the switching FET role, with a lower level of gate charge that is well-suited to the shorter duty cycle of the upper position. The Si4874DY/Si4884DY combination can make 500 MHz notebooks feasible, it is said.