Arrangement and system for an inductive sensor push-button

摘要

Inductive touch key switch system comprises inductive touch key switch assemblies (200), each of which includes conductive target coupled to sensor coil (214); and driver circuits that produce drive current and each includes its own drive transistor. Each driver circuit provides drive current to only one of inductive touch key switch assemblies. The driver circuits is provided on printed circuit board (PCB) (219) local to one inductive touch key switch assembly to which it provides drive current. Lead connection of each sensor coil of each inductive touch key assemblies is tied directly to ground. The system also includes frame disposed between PCB and front panel portion (218) of inductive touch key switch assembly; and light emitter on PCB. The frame has bridging section (216a) with top surface adjacent to under-surface of front panel portion and bottom surface facing towards sensor coil, such that conductive target (212) is proximal to bottom surface of bridging portion, thus flexure of front panel portion above frame (216) results in flexure of bridging section and movement of portion of conductive target towards sensor coil (214). Portion of frame is fabricated from light transmissive material to form light transmissive portion in optical communication with light emitter. The conductive target is metal disc, multi-leaf target, or conductive cap between PCB and boss portion and over sensor coil.