The 74HC153; 74HCT153 is a dual 4-input multiplexer. The device features independent
enable inputs (nE) and common data select inputs (S0 and S1). For each multiplexer, the
select inputs select one of the four binary inputs and routes it to the multiplexer output
(nY). A HIGH on E forces the corresponding multiplexer outputs LOW. Inputs include
clamp diodes. This enables the use of current limiting resistors to interface inputs to
voltages in excess of VCC.