The SN74HC164N chip is an 8-bit shift register and has a CLR input and a serial input with logic I. Inputs A and B according to the scheme provide full control over incoming data:a low level on any of the inputs prohibits the input of new data and resets the first trigger to a low level at the next CLK clock pulse.The high-level input includes another input that determines the state of the first trigger.The outputs of the chip can control up to 8 loads.

The supply voltage is from 2 to 6 Volts, the current consumption is 80 uA, the output current is 4 mA.