Patent · US Expired

Overcurrent protective device for power device

US5394287A · kind A · utility

5Cited by
2References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 29, 1993
Grant dateFeb 28, 1995
Priority date
Expiry dateJan 29, 2013

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03K2017/0806
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A TSD (8) is provided in the vicinity of an IGBT (1), and reference voltages (VR1 to VR5) are provided to the negative inputs of comparators (51 to 55) as a function of a temperature detection signal (S8). A sense terminal (3) of the IGBT is connected to the positive inputs of the comparators (51 to 55) in common. An output signal (S51) of the comparator (51) and output signals (S72 to S75) of signal judging circuits (72 to 75) having received the output signals (S52 to S55) are applied to the input of an NOR gate (6) for on/off control of the IGBT. The signal judging circuits (72 to 75) normally output an L-level judgment signal (S7) and output an H-level judgment signal (S7) when the input signal is at the H level for periods of time that are not shorter than allowable durations (.DELTA.t2 to .DELTA.t5 ), respectively. This provides an overcurrent protective device for a power device which performs overcurrent protective operation adapted for a practical safe operating area of the power device.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.