This document is about SAA1300, SAA1300 is a switch circuit that is used to turn on and off the power lines of various circuit parts via an I2C bus signal. It can also be used to supply current for switching diodes in radio and television tuners. It contains 5 output stages, which are capable of supplying up to 85 mA in the ON state or sinking up to −100 µA in the OFF state. Current limiting and short-circuit protection are included. The output stages are driven by a shift register/latch combination which is loaded via data from the I2C bus. A power-on reset of the latches ensures the OFF state of the output stages (OUT 2 to OUT 5) without data reception from the I2C bus. A subaddressing system allows the connection of up to three circuits on the same I2C bus lines; one of the outputs (OUT 1, pin 7) can also be used as an input to select the device via a simple internal A/D converter.