公开(公告)号：JPS63274326A

公开(公告)日：1988-11-11

申请号：JP9333088

申请日：1988-04-15

Applicant: TANDEM COMPUTERS INC

Inventor： RARII DEIBUITSUDO RIIBUSU ,  JIEI ARIN ZUWAGAAMAN

IPC: H02H9/02 ,  H02H3/05 ,  H02H3/087

Abstract: A fault tolerant, failsafe power supply system for use in a power supply having an output port coupled to a preselected number of output terminals each providing power at a fixed voltage to an associated load circuit for supplying a fixed voltage to each load circuit. The power supply incudes a ground terminal and a power enable port for receiving an enable signal and turning off the power supply when the enable signal is active. A fault tolerant/failsafe current limit system for preventing an overcurrent condition in a load circuit coupled to a selected output terminal is provided and comprises: a first monitor circuit, external to the power supply and coupling a first output terminal to a first load circuit and supplying current thereto, for generating a first output signal in a first state if an overcurrent condition is detected and in a second state if no overcurrent condition is detected; and a second monitor circuit, external to the power supply and coupling a second output terminal to a second load circuit and supplying current thereto, for generating a first output signal in a first state if an overcurrent condition is detected and in a second state if no overcurrent condition is detected; means, adapted to receive both monitor output signals, for shutting off the power supply to prevent an overcurrent condition unless both monitor circuit output signals are in the second state.