What is Current Boosting in Voltage Regulator?
Current Boosting in Voltage Regulator – IC723 regulator is limited to provide a maximum current of 140 mA. To increase its current capacity, we add a transistor Q by connecting its collector to pin 11, base to pin 10, and emitter to pin 2, as shown in Fig. 43.38.
Thus, the collector current of transistor Q comes from unregulated dc supply. The pin 10, or say output current from Vout is into the base of the transistor, so that
Thus, the maximum current handling capacity of IC723 gets increased by factor current gain β of the connected transistor.