A
PPLICATION
N
OTE
A V A I L A B L E
AN42 • AN44–48 • AN50 • AN52 • AN53 • AN71 • AN92
Terminal Voltage ±5V, 100 Taps, Log Taper
X9C303
Digitally Controlled Potentiometer (XDCP
™
)
FEATURES
• Solid-state potentiometer
• Three-wire serial interface
• 100 wiper tap points
—Wiper position stored in nonvolatile memory
and recalled on power-up
• 99 resistive elements, log taper
—Temperature compensated
—End to end resistance, ±15%
—Terminal voltages, ±5V
• Low power CMOS
—V
CC
= 5V
—Active current, 3mA max.
—Standby current, 750µA max.
• High reliability
—Endurance, 100,000 data changes per bit
—Register data retention, 100 years
• X9C303, 32 k
Ω
• Packages
—8-lead TSSOP
—8-lead SOIC
—8-pin DIP
DESCRIPTION
The Xicor X9C303 is a digitally controlled potentiome-
ter (XDCP). The device consists of a resistor array,
wiper switches, a control section, and nonvolatile
memory. The wiper position is controlled by a three-
wire interface.
The resistor array is composed of 99 resistive ele-
ments. Between each element and at either end are
tap points accessible to the wiper terminal. The posi-
tion of the wiper element is controlled by the CS, U/D,
and INC inputs. The position of the wiper can be
stored in nonvolatile memory and then be recalled
upon a subsequent power-up operation.
The device can be used as a three-terminal potentio-
meter or as a two-terminal variable resistor in a wide
variety of applications ranging from control, to signal
processing, to parameter adjustment. Digitally-
controlled potentiometers provide three powerful appli-
cation advantages; (1) the variability and reliability of a
solid-state potentiometer, (2) the flexibility of com-
puter-based digital controls, and (3) the use of nonvol-
atile memory for potentiometer settings retention.
BLOCK DIAGRAM
U/D
INC
CS
7-Bit
Up/Down
Counter
99
98
97
7-Bit
Nonvolatile
Memory
96
One
of
One-
Hundred
Decoder
2
Store and
Recall
Control
Circuitry
1
0
R
L/
V
L
R
W/
V
W
XDCP
™
is a trademark of Xicor, Inc.
REV 1.1 4/27/01
R
H/
V
H
Transfer
Gates
Resistor
Array
V
CC
V
SS
www.xicor.com
Characteristics subject to change without notice.
1 of 10
XICOR [ XICOR INC. ]
