PDF datasheet of 479 KB for the FDMS3660S, a dual N-channel PowerTrench power stage MOSFET from onsemi (originally Fairchild) housing control and synchronous switches in one Power56 package. It is common in notebook core and system voltage regulators. Technicians consult the pinout to locate the switch node, gate pins and drain tabs when tracing a short to ground on a power rail, and use the electrical ratings to judge replacements. Verify the package marking on the board corresponds to this part before replacing it.
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