Tell me the functions of the bus-hold product.

The following figure shows a bus-hold circuit.

[Figure: bus-hold circuit]

The bus-hold circuit is a latch circuit, so CMOS input can be left open. External pull-up resistance or pull-down resistance can be eliminated. In addition, compared to the method to process either side by a pull-up resistance or pull-down resistance, consumption current can be lowered because the level right before high impedance can be retained.