IN74HC257A
TECHNICAL DATA
Quad 2-Input Data Selector/Multiplexer with 3-State Outputs
High-Performance Silicon-Gate CMOS
The IN74HC257A is identical in pinout to the LS/ALS257. The device inputs are patible with standard CMOS outputs; with pullup resistors, they are patible with LS/ALSTTL outputs. This device selects a (4-bit) nibble from either the A or B inputs as determined by the Select input. The nibble is presented at the outputs in noninverted from when the Output Enable pin is at a low level. A high level on the Output Enable pin switches the outputs into the highimpedance state.
- Outputs Directly Interface to CMOS, NMOS, and TTL
- Operating Voltage Range: 2.0 to 6.0 V
- Low Input Current: 1.0 µA
- High Noise Immunity Characteristic of CMOS Devices
ORDERING INFORMATION IN74HC257AN Plastic IN74HC257AD SOIC TA = -55° to 125° C for all packages
PIN ASSIGNMENT LOGIC DIAGRAM
FUNCTION TABLE
Inputs Output Enable H L PIN 16 =VCC PIN 8 = GND Select X L H Outputs Y0-Y3 Z A0-A3...
