| 摘要 |
PURPOSE:To realize overdrive circuit in which the number of externally attached parts, etc., can be reduced. CONSTITUTION:This circuit is provided with a first current source which consists of a resistor element R14 and a pnp type transistor group PG12 and supplies an overdrive current IPG12, a second current source which consists of a resistor element R12 and a pnp type transistor group PG11 and supplies a steady state current IPG11, a resistor element R13 connected to a power supply voltage VCC, a transistor Q12 whose base is connected to the resistor element R13, and which supplies a current IFPG12 by a first current for a prescribed time after the current supply is started, and a transistor Q11 in which the collector is connected to the base of the transistor Q12, the base is connected to one end of a diode Q13 and a resistor element R11, and the emitter is connected to the other end of the resistor element R11 and the emitter of the transistor Q12, and which stops an operation of a first current source operated by the transistor Q12 after the lapse of a prescribed time, and simultaneously, supplies the current IPG11 by actuating a second current source. |
