公开(公告)号：JPH0887338A

公开(公告)日：1996-04-02

申请号：JP16185895

申请日：1995-06-28

Applicant: TANDEM COMPUTERS INC

Inventor： DEIBUITSUDO ERU OORUDORITSUJI ,  UIRIAMU PII BANTON ,  SUTEIIBUN AARU BIISERU ,  DEIBUITSUDO BURAUN ,  DANIERU DEII GAN ,  KAARU KAAGII ,  DEIBUITSUDO PII SOONIA

IPC: H02J9/00 ,  G01R31/28 ,  G01R31/40 ,  G05F1/00 ,  G06F11/00 ,  G06F11/20 ,  H02J1/00 ,  H02J9/06

Abstract: PURPOSE: To test a potential fault in a power mixing device by providing first and second power rail and the power mixing device in a circuit module. CONSTITUTION: The first power rail 30 of a circuit 10 is connected to the input of a DC controller(DCC) 32 through a first fuse 34, a first power path transistor 36 and a first isolation diode 38 which are mutually serially connected. Similarly a second power rail 40 is connected to the input of DCC 32 through a second fuse 44, a second power path transistor 46 and a second isolation diode 48 which are mutually serially connected. In addition a first test circuit 80 is provided with a first test opto-isolator 82 and its control input is connected to a first test node 84 arranged between the drain of a first power path N-channel MOS transistor 36 and the cathode of the first isolation diode 38. Consequently, a potential fault test is made possible at the power mixing device.