DESCRIPTION
The M54/74HC258 is an inverting multiplexer while the M54/74HC257 is a non-inverting multiplexer. When the ENABLE INPUT is held ”High”, outputs of both IC’s become high-impedance state. If SELECT INPUT is held ”Low”, ”A” data is selected, when SELECT INPUT is high ”H”, ”B” data is chosen. All inputs are equipped with protection circuits against static discharge and transient excess voltage. October 1992 HC258 1/12 M54/M74HC257/258 INPUT AND OUTPUT EQUIVALENT CIRCUIT CHIP CARRIER HC257 HC258 NC = No Internal Connection PIN DESCRIPTION
(HC257) PIN No 1 2, 5, 14, 11 3, 6, 13, 10 4, 7, 12, 9 15 8 16 SYMBOL SELECT 1A to 4A 1B to 4B 1Y to 4Y OE GND V CC NAME AND FUNCTION Common Data Select Input Data Input From Source A Data Inputs from Source B 3 State Multiplexer Outputs 3 State Output Enable Inputs (Active LOW) Ground (0V) Positive Supply Voltage PIN DESCRIPTION
(HC258) PIN No 1 2, 5, 14, 11 3, 6, 13, 10 4, 7, 12, 9 15 8 16 SYMBOL SELECT 1A to 4A 1B to 4B 1Y to 4Y OE GND VCC N...
STMicroelectronics
