TWO WIRE OUTPUT/POWER MECHANISM FOR REMOTE DEVICES

摘要

An interface that provides selected information from a remote device to a utilization mechanism over a two-wire connection, wherein all power for the interface and the remote device is received from the utilization mechanism over the same two-wire connection. A switch circuit provides a high impedanc e between first and second wires of the two-wire connection when open and a lo w impedance between the wires when closed. Current flow through the switch circuit is sensed by the utilization mechanism as indicative of information from the remote device. The interface comprises a voltage regulator that provides a regulated voltage to components of the interface and the remote device, and a current regulator that regulates current provided to the volta ge regulator from the two-wire connection, when the switch circuit is open, to below a predetermined level at which the utilization mechanism interprets th e switch circuit as being in the open state.