Patent ID: 6653845
Filing Date: 2003-11-25
Classification: G01R

Abstract:
An open circuit detection apparatus for detecting whether a connection is closed between a local node and a remote node having a known impedance, the apparatus comprising:a ping source connected to the local node, said ping source further comprising an output for transmitting an address unique to the remote node; and an input for sensing the impedance of one of a plurality of remote nodes; a plurality of test circuits, each test circuit being connected to one of said plurality of remote nodes and each test circuit further comprising an address decoder for receiving said address from said output, said address decoder having a unique address; a control signal, said address decoder asserting said control signal upon said address matching said unique address of said address decoder; and an impedance varying device being responsive to said control signal, said impedance varying device effecting a change in the impedance of its remote node; and said change in the impedance of the remote node being sensed by said input of said ping source.