CD74FCT245

BiCMOS OCTAL BUS TRANSCEIVER

WITH 3-STATE OUTPUTS

SCBS721 – 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 CD74FCT245 is an octal bus transceiver with 3-state outputs using a small-geometry BiCMOS technology.

The output stages are a combination of bipolar and CMOS transistors that limit the output high level to two diode

drops below VCC. This resultant lowering of output swing (0 V to 3.7 V) reduces the 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.

The CD74FCT245 allows data transmission from the A bus to the B bus or from the B bus to the A bus,

depending upon the logic level at the direction-control (DIR) input. The output-enable (OE) input can be used

to disable the device so that the buses are effectively isolated.

To ensure the high-impedance state during power up or power down, OE should be tied to VCC through a pullup

resistor; the minimum value of the resistor is determined by the current-sinking capability of the driver.

The CD74FCT245 is characterized for operation from 0

°C to 70°C.

FUNCTION TABLE

INPUTS

OPERATION

OE

DIR

OPERATION

L

L

B data to A bus

L

H

A data to B bus

H

X

Isolation

Copyright

© 2000, Texas Instruments Incorporated

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.

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

(TOP VIEW)

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20

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DIR

A1

A2

A3

A4

A5

A6

A7

A8

GND

VCC

OE

B1

B2

B3

B4

B5

B6

B7

B8