Philips Semiconductors

Product specification

74F621

Octal bus transceiver, non-inverting (open collector)

1996 Jan 05

3

LOGIC SYMBOL

B0

B1

B2

B3

19

1

OEAB

OEBA

SF01126

GND = Pin 10

B4

B5

B6

B7

89

A2

A3

45

6

A4

A5

A6

7

A7

23

A0

A1

18

17

16

15

14

13

12

11

LOGIC SYMBOL (IEEE/IEC)

SF01137

19

18

EN1

1

17

16

15

14

13

12

11

2

3

4

5

6

7

8

9

2

1

EN2

LOGIC DIAGRAM

VCC =

Pin 20

GND =

Pin 10

SF01130

OEBA

2

3

4

18

17

16

15

14

13

12

B0

B1

B4

B5

B6

B7

OEAB

A1

A4

A5

A6

A7

B2

B3

A3

A2

5

6

7

8

A0

11

9

19

1

FUNCTION TABLE

INPUTS

OPERATING MODES

OEBA

OEAB

OPERATING MODES

L

L

B data to A bus

H

H

A data to B bus

H

L

OFF

L

H

B data to A bus

L

H

A data to B bus

H = High voltage level

L

= Low voltage level

X = Don’t care

OFF= High if pull-up resistor is connected to open collector output