74HC_HCT257.pdf

General description

The 74HC257; 74HCT257 are high-speed Si-gate CMOS devices and are pin compatible with Low-power Schottky TTL (LSTTL).

The 74HC257 and 74HCT257 have four identical 2-input multiplexers with 3-state outputs, which select 4 bits of data from two sources and are controlled by a common data select input (S).

The data inputs from source 0 (1I0 to 4I0) are selected when input S is LOW and the data inputs from source 1 (1I1 to 4I1) are selected when S is HIGH. Data appears at the outputs (1Y to 4Y) in true (non-inverting) form from the selected inputs.

The 74HC257 and 74HCT257 are the logic implementation of a 4-pole, 2-position switch, where the position of the switch is determined by the logic levels applied to S. The outputs are forced to a high-impedance OFF-state when OE is HIGH.

The logic equations for the outputs are: Except for their non-inverting (true) outputs the 74HC257; 74HCT257 are identical to the 74HC258.

Features

• Non-inverting data path
• 3-state outputs interface directly with system bus
• Complies with JEDEC standard no. 7A
• ESD protection:
  • HBM JESD22-A114E exceeds 2000 V
  • MM JESD22-A115-A exceeds 200 V
• Multiple package options
• Specified from -40 °C to +85 °C and from -40 °C to +125 °C

Products/packages

Quality/reliability/chemical content

Quality and reliability disclaimer

Pricing/ordering/availability

Block diagrams/pinning

Design support

Support Documents

HCT_USER_GUIDE; HC/T User Guide (1997-11-01)

Parametrics/similar products

Similar products
74HC_HCT257.pdf links to the similar products page containing an overview of products that are similar in function or related to the type number(s) as listed on this page. The similar products page includes products from the same catalog tree(s), relevant selection guides and products from the same functional category.

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Disclaimers

• General product disclaimer
• Quality and reliability disclaimer