KK74HC257A

TECHNICAL DATA KK74HC257A Quad 2-Input Data Selector/Multiplexer with 3-State Outputs High-Performance Silicon-Gate CMOS The KK74HC257A is identical in pinout to the LS/ALS257. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible 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 KK74HC257AN Plastic KK74HC257AD 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 L Select X L H Outputs Y0-Y3 Z A0-A3 B0-B3 X=don’t care Z = high-impedance state A0-A3,B0-B3=the levels of the respective Nibble Inputs www.DataSheet4U.net 1 KK74HC257A MAXIMUM RATINGS* Symbol VCC VIN VOUT IIN IOUT ICC PD Tstg TL * Parameter DC Supply Voltage (Referenced to GND) DC Input Voltage (Referenced to GND) DC Output Voltage (Referenced to GND) DC Input Current, per Pin DC Output Current, per Pin DC Supply Current, VCC and GND Pins Power Dissipation in Still Air, Plastic DIP+ SOIC Package+ Storage Temperature Lead...