REV 1.1.9 1/30/03

Characteristics subject to change without notice.

2 of 26

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X9521

– Preliminary Information

PIN ASSIGNMENT

Pin

CSP

Name

Function

1B3

Connection to end of resistor array for (the 256 Tap) DCP 2.

2A3

Connection to terminal equivalent to the “Wiper” of a mechanical potentiometer for DCP 2.

3A4

Connection to other end of resistor array for (the 256 Tap) DCP2.

7C4

WP

Write Protect Control Pin. WP pin is a TTL level compatible input. When held HIGH, Write

Protection is enabled. In the enabled state, this pin prevents all nonvolatile “write” opera-

tions. Also, when the Write Protection is enabled, and the device Block Lock feature is active

(i.e. the Block Lock bits are NOT [0,0]), then no “write” (volatile or nonvolatile) operations

can be performed in the device (including the wiper position of any of the integrated Digitally

Controlled Potentiometers (DCPs). The WP pin uses an internal “pull-down” resistor, thus if

left floating the write protection feature is disabled.

8

D4

SCL

Serial Clock. This is a TTL level compatible input pin used to control the serial bus timing for

data input and output.

9E4

SDA

Serial Data. SDA is a bidirectional TTL level compatible pin used to transfer data into and

out of the device. The SDA pin input buffer is always active (not gated). This pin requires

an external pull up resistor.

10

E1

Vss

Ground.

11

E3

Connection to other end of resistor for (the 100 Tap) DCP 1.

12

E2

Connection to terminal equivalent to the “Wiper” of a mechanical potentiometer for DCP 1

13

D1

Connection to end of resistor array for (the 100 Tap) DCP 1.

20

A2

Vcc

Supply Voltage.

4, 5, 6,

14, 15,

16, 17,

18, 19

A1, B1,

B2, B4,

C1, C2,

C3, D2,

D3

NC

No Connect

PIN CONFIGURATION

NC

NC

3

4

Vcc

SCL

NC

NC

7

8

NC

10

1

18

19

17

20

14

15

13

16

12

11

NC

6

2

SDA

9

NC

5

WP

NC

NC

NOT TO SCALE

2

3

4

A

B

C

D

E

Top View – Bumps Down

1

CSP

20 Pin TSSOP

NC

WP

NC

SCL

NC

SDA

NC

V1/Vcc

NC

NC

NC

NC

NC