The primary function of the 4-bit 2-to-1 I²C multiplexer is to select either a 4-bit input or
data from a non-volatile register and drive this value onto the output pins. One additional
non-multiplexed register output is also provided. The non-multiplexed output is latched to
prevent output value changes during I²C writes to the non-volatile register. A write protect
input is provided to enable/disable the ability to write to the non-volatile register. An
"override" input feature forces all outputs to logic 0.