The LK112S is a low dropout linear regulator with a built-in electronic switch. The internal switch can be controlled by TTL or CMOS logic levels. The device is ON state when the control pin is pulled to a logic high level. An external capacitor can be used connected to the noise bypass pin to lower the output noise level to 30µVrms. An internal PNP pass transistor is used to achieve a low dropout voltage. The LK112S has a very low quiescent current in ON MODE while in OFF MODE the Iq is reduced down to 100nA max. The internal thermal shutdown circuitry limits the junction temperature to below 150°C. The load current is internally monitored and the device will shutdown in the presence of a short circuit or overcurrent condition at the output.