公开(公告)号：JPH07175537A

公开(公告)日：1995-07-14

申请号：JP14900394

申请日：1994-06-30

Applicant: TANDEM COMPUTERS INC

Inventor： MAAKU EI TEIRAA ,  SAMUSON KEI TOI

IPC: G06F1/28 ,  G05F1/56 ,  G06F12/16 ,  G11C11/413 ,  H02J7/00 ,  H02J9/06

Abstract: PURPOSE: To generate a regulated low D.C. voltage from a pair of redundant batteries by providing a control circuit means with an unregulated voltage for generating a control signal and a sensing means connected to the control circuit means. CONSTITUTION: A regulator system 10 is provided with a variable impedance connected to the positive terminals of the two batteries VB1 and VB2 in order to supply the regulated voltage Vr. The variable impedance 12 keeps the balance of current which is drawn from the batteries VB1 and VB2 and is functioned to lower the D.C. voltage supplied by the batteries to be the lower voltage Vr . When change is executed from the required adjusted voltage Vr , an error signal Ve is generated by the control circuit. The regulator system 10 is provided with respectively related battery sensing circuits 16a and 16b as against the batteries VB1 and VB2 and then battery sensing circuits 16 are operated to track the terminal voltages of the respective batteries.

公开(公告)号：JPH07146721A

公开(公告)日：1995-06-06

申请号：JP14731794

申请日：1994-06-29

Applicant: TANDEM COMPUTERS INC

Inventor： MAAKU EI TEIRAA ,  SAMUSON KEI TOI

IPC: G01R19/165 ,  G05F1/10 ,  G05F1/56 ,  G06F1/28 ,  H03K17/22

Abstract: PURPOSE: To supply the valid instruction of the state of a supply voltage during an initial stage for applying the supply voltage by providing a supply voltage monitor and a protective circuit. CONSTITUTION: When the supply voltage Vcc reaches a first voltage level, the supply voltage monitor U1 turns on a transistor Q1. When the supply voltage Vcc reaches a second voltage level, the shunt regulator U2 of the protective circuit 14 is conducted and the voltage of a node A is lowered towards a ground potential. The open collector output of the transistor Q1 keeps the supply of a current and the transistor Q2 is not conducted because a large voltage drop is present between a resistor R3. When the supply voltage Vcc reaches a third voltage level, the monitor U1 turns off the transistor Q1. The shunt regulator U2 continues conducting, the base of the transistor Q2 is grounded and the transistor Q2 is conducted. The current flowing the resistor R6 asserts PON (power ON) signals.