摘要 |
An integrated circuit is provided which uses a single drive signal for turning a PNP switching transistor "on" and "off." An NPN transistor provides reverse drive current to the PNP transistor's base. When the drive signal is present, the PNP switching transistor is turned "on" and is driven into saturation. The drive signal during this period also charges an integrated capacitor coupled to the base of the NPN transistor. The drive signal then is removed to turn the PNP transistor "off." Removal of the drive signal also causes the voltage developed across the capacitor to drive the base of the NPN transistor. This, in turn, causes the NPN transistor to drive the base of the PNP transistor with a reverse drive current, thus speeding up the switching of the PNP transistor from the conducting state to the non-conducting state.
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