2

Description

The Harris CD54HC245, CD54HCT245, and CD74HC245,

CD74HCT245 are high-speed octal three-state bidirectional

transceivers

intended

for

two-way

asynchronous

communication between data buses. They have high drive

current outputs which enable high-speed operation while

driving large bus capacitances. They provide the low power

consumption of standard CMOS circuits with speeds and

drive capabilities comparable to that of LSTTL circuits.

The

CD54HC245,

CD54HCT245,

CD74HC245

and

CD74HCT245 allow data transmission of the B bus or from

the B bus to the A bus. The logic level at the direction input

(DIR) determines the direction. The output enable input

(OE), when high, puts the I/O ports in the high-impedance

state.

The HC/HCT245 is similar in operation to the HC/HCT640

and the HC/HCT643.

Functional Diagram

Ordering Information

PART NUMBER

TEMP.

PACKAGE

PKG.

NO.

CD54HC245F

-55 to 125

20 Ld CERDIP

F20.3

CD54HCT245F

-55 to 125

20 Ld CERDIP

F20.3

CD74HC245E

-55 to 125

20 Ld PDIP

E20.3

CD74HCT245E

-55 to 125

20 Ld PDIP

E20.3

CD74HC245M

-55 to 125

20 Ld SOIC

M20.3

CD74HCT245M

-55 to 125

20 Ld SOIC

M20.3

NOTES:

1. When ordering, use the entire part number. Add the suffix 96 to

obtain the variant in the tape and reel.

2. Wafer or die for this part number is available which meets all elec-

trical specifications. Please contact your local sales office or

Harris customer service for ordering information.

18

17

16

15

13

11

12

14

2

B0

B1

B2

B3

B4

B5

B6

B7

OE

DIR

1

19

4

9

3

5

6

7

8

A0

A1

A2

A3

A4

A5

A6

A7

TRUTH TABLE

CONTROL INPUTS

OPERATION

OE

DIR

L

L

B Data to A Bus

L

H

A Data to B Bus

H

X

Isolation

H = High Level, L = Low Level, X = Irrelevant

To prevent excess currents in the High-Z (Isolation) modes all I/O

terminals should be terminated with 10k

Ω to 1MΩ resistors.

CD54HC245, CD54HCT245, CD74HC245, CD74HCT245

CD54HC245, CD54HCT245, CD74HC245, CD74HCT245