Fairchild Semiconductor 74FR2245SC, 74FR2245SCX Datasheet

© 1999 Fairchild Semiconductor Corporation DS012114 www.fairchildsemi.com

April 1995
Revised August 1999

74FR2245 Octal Bidirectional Transceiver with 3-STATE Outputs

74FR2245
Octal Bidirectional Transceiver with 3-STATE Outputs

General Description

The 74FR2245 contains eight non-inverting bidirectional
buffers with 3-STATE outputs and is intended for bu s-ori­ented applications. Current sinking capability is 64 mA on
the A Port. The Transmit/Rece ive (T/R

) input determines
the direction of data flow through the bidirectional trans­ceiver. Transmit (active-HIGH) enables data from A Ports
to B Ports; Receive (active-LOW) enables data from B
Ports to A Ports. The Output Enable input, when HIGH, dis­ables both A and B Ports by plac ing them in a High Z con­dition.

Features

■ Non-inverting buffers

■ Bidirectional data path

■ Guaranteed pin-to-pin skew

■ 25Ω series resistors in B outputs eliminate the need for

external resistors

■ 3-STATE outputs drive bus lines or buffer memory
address resistors

Ordering Code:

Devices also availab le in Tape and Reel. Specify by appending th e s uffix let t er “X” letter to the ordering co de.

Logic Symbol

Pin Descriptions

Connection Diagram

Truth Table

H = HIGH Voltage Level
L = LOW Voltage Level
X = Immaterial

Order Number Package Number Package Description

74FR2245SC M20B 20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide

Pin Names Description

OE

Output Enable Input (Active-LOW)

T/R

Transmit/Receive Input

A

0–A7

Side A Inputs or 3-STATE Outputs

B

0–B7

Side B Inputs or 3-STATE Outputs

Inputs Output

OE

T/R

L L Bus B Data to Bus A
L H Bus A Data to Bus B
H X High Z State

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74FR2245

Logic Diagram