To provide a load drive control circuit which can make a status that an overcurrent flows into a semiconductor element in a circuit hardly occur even if a connecting terminal of the circuit is short-circuited to a positive pole of a power supply in a state that a load is stopped, and also can make an erroneous operation of the load hardly occur.
A first bridge circuit 7 connected to one motor terminal of a motor M and a second bridge circuit 8 connected to the other motor terminal of the motor M are arranged in the drive control circuit 6 in an H-bridge motor drive circuit. The drive control circuit 6 detects a current flowing in the circuit by using current detection transistors Cs1 to Cs4, and when the detected value is abnormal, the circuit determines that a short-circuiting to a positive pole of the power supply has occurred. When the drive control circuit 6 recognizes that the short-circuiting has occurred when the motor M is stopped, the drive control circuit brings the two bridge circuits 7, 8 into Hi-Z states, and conducts processing for electrically separating the motor M from a power supply Vcc.
JP2002091235 | IMAGE FORMING DEVICE |
JP2559706 | INDUSTRIAL APPLICABILITY: Control device for AC elevator |
KISHI DAIKI
JP2002204593A | 2002-07-19 |
WO2003039208A1 | 2003-05-08 |
Makoto Onda
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