2

FN8223.0

March 11, 2005

PIN DESCRIPTIONS

equivalent to the fixed terminals of a mechanical

potentiometer. The minimum voltage is –5V and the

maximum is +5V. It should be noted that the terminol-

terminal in relation to wiper movement direction

selected by the U/D input and not the voltage potential

on the terminal.

terminal of a mechanical potentiometer. The position

of the wiper within the array is determined by the con-

trol inputs. The wiper terminal series resistance is typi-

cally 40

Ω.

Up/Down (U/D)

The U/D input controls the direction of the wiper

movement and whether the counter is incriminated or

decremented.

Increment (INC)

The INC input is negative-edge triggered. Toggling

INC will move the wiper and either increment or decre-

ment the counter in the direction indicated by the logic

level on the U/D input.

Chip Select (CS)

The device is selected when the CS input is LOW. The

current counter value is stored in nonvolatile memory

when CS is returned HIGH while the INC input is also

HIGH. After the store operation is complete the device

will be placed in the low power standby mode until the

device is selected once again.

PIN CONFIGURATION

PIN NAMES

POTENTIOMETER RELATIONSHIPS

CS

INC

U/D

1

2

3

4

8

7

6

5

X9C303

DIP/SOIC/(TSSOP)

(CS)

(INC)

(U/D)

Symbol

Description

High Terminal (Potentiometer)

Wiper Terminal (Potentiometer)

Low Terminal (Potentiometer)

Ground

Supply Voltage

U/D

Up/Down Control Input

INC

Increment Control Input

CS

Chip Select Control Input

NC

No Connection

R99

R98

R2

R1

S100

S99

S98

S3

S2

S1

G

i

20Log

R

1

R

2

. . .

R

i

++

+

R

TOTAL

-------------------------------------------------

V

W

V

S

--------- V

L

0V

=

()

==

R

1

R

2

. . .

R

99

++

+

3

k

Ω

@R

TOTAL

=

(Refer Test Circuit 1)

X9C303