18-Bit Registered Transceiver

CY74FCT163500

SCCS066 - June 1997 - Revised March 2000

Data sheet acquired from Cypress Semiconductor Corporation.

Data sheet modified to remove devices not offered.

Copyright

Features

• Low power, pin-compatible replacement for LCX and

LPT families

• 5V tolerant inputs and outputs

• 24 mA balanced drive outputs

• Power-off disable outputs permits live insertion

• Edge-rate control circuitry for reduced noise

• FCT-C speed at 4.6 ns

• Latch-up performance exceeds JEDEC standard no. 17

• ESD > 2000V per MIL-STD-883D, Method 3015

• Typical output skew < 250ps

• Industrial temperature range of –40˚C to +85˚C

• TSSOP (19.6-mil pitch) or SSOP (25-mil pitch)

Std 883D

Functional Description

The CY74FCT163500 is an 18-bit universal bus transceiver

that can be operated in transparent, latched, or clock modes

by combining D-type latches and D-type flip-flops. Data flow in

each direction is controlled by output-enable (OEAB and

OEBA), latch enable (LEAB and LEBA), and clock inputs

(CLKAB and CLKBA) inputs. For A-to-B data flow, the device

operates in transparent mode when LEAB is HIGH. When

LEAB is LOW, the A data is latched if CLKAB is held at a HIGH

or LOW logic level. If LEAB is LOW, the A bus data is stored in

the latch/flip-flop on the HIGH-to-LOW transition of CLKAB.

OEAB performs the output enable function on the B port. Data

flow from B-to-A is similar to that of A-to-B and is controlled by

OEBA, LEBA, and CLKBA.

The CY74FCT163500 has 24-mA balanced output drivers

with current limiting resistors in the outputs. This reduces the

need for external terminating resistors and provides for

minimal undershoot and reduced ground bounce.The inputs

and outputs are capable of being driven by 5.0V busses,

allowing them to be used in mixed voltage systems as

translators. The outputs are also designed with a power off

disable feature enabling them to be used in applications

requiring live insertion.

GND

Logic Block Diagram

Pin Configuration

1

2

3

4

5

6

7

8

9

10

11

12

33

32

31

30

29

36

35

OEAB

34

SSOP/TSSOP

Top View

13

14

15

16

17

18

19

20

21

22

23

24

45

44

43

42

41

37

38

39

40

48

47

46

LEAB

GND

GND

GND

GND

GND

GND

TO 17 OTHER CHANNELS

LEAB

OEBA

LEBA

CLKAB

CLKBA

OEAB

C

D

C

D

C

D

C

D

25

26

27

28

49

52

51

50

OEBA

LEBA

GND

CLKAB

53

56

55

54

GND

GND

CLKBA