The TK112xxB is a low dropout linear regulator with a builtin electronic switch. The internal switch can be controlled by TTL or CMOS logic levels. The device is in the "on" state when the control pin is pulled to a logic high level. An external capacitor can be connected to the noise bypass pin to lower the output noise level to 30 Vrms. An internal PNP pass transistor is used to achieve a low dropout voltage of 80 mV (typ.) at 30 mA load current. The TK112xxB has a very low quiescent current of 170 A at no load and 1 mA with a 30 mA load. The standby current is typically 100 nA. The internal thermal shut down circuitry limits the junction temperature to below 150 C. The load current is internally monitored and the device will shut down in the presence of a short circuit or overcurrent condition at the output.