Title:
OVERCURRENT PROTECTOR FOR FIELD EFFECT TRANSISTOR
Document Type and Number:
Japanese Patent JPH0622445
Kind Code:
A
Abstract:
PURPOSE: To provide an overcurrent protector for FET which can protect a FET (Field Effect Transistor) accurately regardless of fluctuation of ON resistance and the like of the FET without requiring sufficient margin for the rated current.
CONSTITUTION: Parallel-connected FETs 112, 114 are connected, respectively, in series with current detecting resistors 136, 137 for detecting the currents flowing through the FETs 112, 114. The currents thus detected are then compared through op. amps 125, 126 with reference values 128, 129 thus detecting overcurrent. Since overcurrent is detected independently for each system with no influence of the value detected for other FET system, accurate overcurrent detection/protection is realized.
Inventors:
KOMATSU SHUNICHI
Application Number:
JP17257092A
Publication Date:
January 28, 1994
Filing Date:
June 30, 1992
Export Citation:
Assignee:
CANON KK
International Classes:
H02H7/12; (IPC1-7): H02H7/12
Attorney, Agent or Firm:
Hiroyuki Niwa (1 outside)
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