Title:
INPUT VOLTAGE CLAMP CIRCUIT
Document Type and Number:
Japanese Patent JP3338711
Kind Code:
B2
Abstract:
PURPOSE: To extract a prescribed clamp voltage regardless of fluctuation of an input current in the input voltage clamp circuit employing bipolar transistors(TRs).
CONSTITUTION: The circuit consists of TRs Q11, Q12 in Darlington connection and a constant voltage circuit 16 comprising a current source 15, a TRQ3 and resistors R1, R2. The constant voltage circuit 16 is a current absorption type constant voltage circuit. A constant current IE is set so that a base current IB12 of a TRQ12 caused by an input current I is sufficiently smaller than a current IE flowing from the current source 15 to the TRQ3 thereby preventing an output constant voltage VREF of the constant voltage circuit 16 is not changed by the base current IB12.
Inventors:
Hidenori Machida
Masatoshi Ikebata
Masatoshi Ikebata
Application Number:
JP12697892A
Publication Date:
October 28, 2002
Filing Date:
May 20, 1992
Export Citation:
Assignee:
NC Microsystem Co., Ltd.
International Classes:
H03G11/08; H03K5/00; H03K5/007; (IPC1-7): H03K5/007; H03G11/08
Attorney, Agent or Firm:
Naoki Kyomoto (2 outside)