Input switching device used in a logic mos integrated circuit.

摘要

A first input signal (6) is supplied to a register (1) and stored therein. The first input signal (6) and data stored in the register 1) are supplied to a first logic circuit (2). The first logic circuit (2) is controlled by an output signal (12) of a flag circuit (21) and selects one of the first input signal (6) and the data (7) stored in the register 1). A second input signal (10) is supplied to a second logic circuit (3). The second logic circuit (3) is controlled by an output signal (12) of the flag circuit (21) and selects one of supplying the second input signal (10) to the register (1) as a clock signal (8) and supplying the second input signal to a peripheral circuit as an input signal (9). The flag circuit (21) supplies the second input signal (10) to the register (1) as the clock signal (8) when the first logic circuit (2) selects the output signal (7) of the register (1), and supplies the second input signal (10) to the peripheral circuit as the input signal (9) when the first logic circuit (2) selects the first input signal (6). <IMAGE>