CD74FCT623

BiCMOS OCTAL BUS TRANSCEIVER

WITH 3-STATE OUTPUTS

SCBS736 – JULY 2000

1

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

D BiCMOS Technology With Low Quiescent

Power

D Buffered Inputs

D Noninverted Outputs

D Input/Output Isolation From VCC

D Controlled Output Edge Rates

D 64-mA Output Sink Current

D Output Voltage Swing Limited to 3.7 V

D SCR Latch-Up-Resistant BiCMOS Process

and Circuit Design

D Package Options Include Plastic

Small-Outline (M) and Shrink Small-Outline

(SM) Packages and Standard Plastic (E) DIP

description

The CD74FCT623 is an octal bus transceiver that uses a small-geometry BiCMOS technology. The output stage

is a combination of bipolar and CMOS transistors that limits the output high level to two diode drops below VCC.

This resultant lowering of output swing (0 V to 3.7 V) reduces power-bus ringing [a source of electromagnetic

interference (EMI)] and minimizes VCC bounce and ground bounce and their effects during simultaneous output

switching. The output configuration also enhances switching speed and is capable of sinking 64 mA.

This device is a noninverting, 3-state, bidirectional transceiver-buffer intended for two-way transmission from

A bus to B bus or B bus to A bus, depending on the logic levels of the output-enable (OEAB, OEBA) inputs.

The dual output-enable provision gives these devices the capability to store data by simultaneously enabling

OEAB and OEBA. Each output reinforces its input under these conditions, and when all other data sources to

the bus lines are at high impedance, both sets of bus lines remain in their last states.

The CD74FCT623 is characterized for operation from 0

°C to 70°C.

FUNCTION TABLE

INPUTS

OPERATION

OEBA

OEAB

OPERATION

L

L

B data to A bus

H

H

A data to B bus

H

L

Isolation†

L

H

B data to A bus,

A data to B bus

† To prevent excess current in the

high-impedance (isolation) state, all I/O

terminals should be terminated with

10-k

Ω to 1-MΩ resistors.

PRODUCTION DATA information is current as of publication date.

Products conform to specifications per the terms of Texas Instruments

standard warranty. Production processing does not necessarily include

testing of all parameters.

Copyright

© 2000, Texas Instruments Incorporated

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of

Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

E, M, OR SM PACKAGE

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OEAB

A1

A2

A3

A4

A5

A6

A7

A8

GND

VCC

OEBA

B1

B2

B3

B4

B5

B6

B7

B8