IN74HC251A

Features:

• 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


Pinout




Specifications

Symbol	Parameter	Value	Unit
VCC	DC Supply Voltage (Referenced to GND)	-0.5 to +7.0	V
VIN	DC Input Voltage (Referenced to GND)	-1.5 to VCC +1.5	V
VOUT	DC Output Voltage (Referenced to GND)	-0.5 to VCC +0.5	V
IIN	DC Input Current, per Pin	±25	mA
IOUT	DC Output Current, per Pin	±50	mA
ICC	DC Supply Current, VCC and GND Pins	±75	mA
PD	Power Dissipation in Still Air, Plastic DIP+                                        SOIC Package+	750 500	mW
Tstg	Storage Temperature	-65 to +150
TL	Lead Temperature, 1 mm from Case for 10 Seconds (Plastic DIP or SOIC Package)	260

*Maximum Ratings are those values beyond which damage to the device may occur.
  Functional operation should be restricted to the Recommended Operating Conditions.
  +Derating - Plastic DIP: - 10 mW/ from 65° to 125
               SOIC Package: : - 7 mW/from 65° to 125


Description

The IN74HC251A is identical in pinout to the LS/ALS251. The device inputs are compatible with standard CMOS outputs; with pullup resistors, they are compatible with LS/ALSTTL outputs.

The IN74HC251A selects one of the eight binary Data Inputs, as determined by the Address Inputs. The Output Enable pin must be at a low level for the selected data to appear at the outputs. If Output Enable is high, the Y and the Y outputs are in the high-impedance state. This 3-State feature allows the IN74HC251A to be used in bus-oriented systems.