| 摘要 |
Accordingly, an integrated control circuit is provided that allows for a central current reference circuit that supplies a reference current signal that employ a zero temperature coefficient. This current reference signal can be proportionally mirrored to a variety of output drivers to allow for a driving of peripheral systems with exact current requirements. Due to the fact that the reference current will not exhibit substantial variation with respect to temperature, the variability in the current supplies to the output drivers is small. As such, the output drivers can be designed to minimize the waste of current and power dissipation in the integrated system. Said output driver circuit (38) provides an output current to a load through an output pin. A output current mirror formed of a plurality of bipolar transistors (180, 188, and 194) provides the output current responsive to a control signal T1. A Schottky transistor (178) shunts current away from the output current mirror circuit responsive to the T1 signal to shut off the output current signal. If the output pin is pulled below ground potential by the load, the Schottky transistor (178) shuts off and the output current is reestablished preventing the activation of substrate diodes and the formation of potentially disruptive substrate currents.
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