| 摘要 |
PROBLEM TO BE SOLVED: To provide a drive circuit which is capable of easily controlling a slew rate while reducing a circuit size as much as possible. SOLUTION: A current value control circuit 31 detects a supply voltage VB and instructs a current output circuit 21 to output a current IH ofβ(fixed value)×VB. When a drive command signal Sd1 is changed to a H level and a drive command signal Sd2 is changed to a L level, a MOSFET 20 is turned on to turn off MOSFETs 14 and 16, and a current of m(mirror ratio)×IH flows to a MOSFET 13. At this time, a charge extracting current IH is caused to flow in a path from a power line 4 to a power line 5 through the MOSFET 13, a gate-drain capacitor Cgd of the MOSFET 13, and a MOSFE 24, and the gate-drain capacitor Cgd of the MOSFE 13 is discharged in a certain time independently of the supply voltage VB. COPYRIGHT: (C)2009,JPO&INPIT
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