FETs Help Make PCs Power-Up Instantly

Serving specifically to facilitate development of next-generation PCs needing to implement ACPI and OnNow, the Si4501DY power MOSFET is designed to help bring a low-cost, "quasi" instant power-up feature to desktop PCs. The FET is used to switch the two voltage rails supplied by an ATX power supply.By allowing part of the circuit to be isolated and powered from the standby supply, the main supply and fan can be turned off while the computer is in the standby mode, thus giving the appearance of the computer being turned off. The device consists of complementary N- and P-channel MOSFETs connected together internally and functioning as a SPDT switch with one control input.