REV 1.1.5 7/8/03
Characteristics subject to change without notice.
1 of 20
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X9428
Single Digitally Controlled Potentiometer (XDCP
)
FEATURES
Solid state potentiometer
2-wire serial interface
Register oriented format
—Direct Read/Write/Transfer Wiper Position
—Store as many as Four Positions per
Potentiometer
Power supplies
—V
CC
= 2.7V to 5.5V
—V+ = 2.7V to 5.5V
—V– = –2.7V to –5.5V
Low power CMOS
—Standby current < 1μA
—Ideal for Battery Operated Applications
High reliability
—Endurance–100,000 Data Changes per Bit per
Register
—Register Data Retention–100 years
4-bytes of nonvolatile memory
10K Ohm resistor array
Resolution: 64 taps each potentiometer
SOIC and TSSOP packages
DESCRIPTION
The
potentiometers (XDCP) on a monolithic CMOS
integrated microcircuit.
X9428
integrates
a
digitally
controlled
The digitally controlled potentiometer is implemented
using 63 resistive elements in a series array. Between
each element are tap points connected to the wiper
terminal through switches. The position of the wiper on
the array is controlled by the user through the 2-wire
bus interface. Each potentiometer has associated with
it a volatile Wiper Counter Register (WCR) and 4
nonvolatile Data Registers (DR0:DR3) that can be
directly written to and read by the user. The contents of
the WCR controls the position of the wiper on the
resistor array through the switches. Power up recalls
the contents of DR0 to the WCR.
The XDCP can be used as a three-terminal
potentiometer or as a two-terminal variable resistor in
a wide variety of applications including control,
parameter adjustments, and signal processing.
BLOCK DIAGRAM
R0 R1
R2 R3
Wiper
Counter
Register
(WCR)
Interface
and
Control
Circuitry
SCL
SDA
A0
A2
A3
V
H
/R
H
V
L
/R
L
Data
8
V
W
/R
W
WP
V
CC
V
SS
V+
V–
Low Noise/Low Power/2-Wire Bus
A
PPLICATION
N
OTES
A V A I L A B L E
AN99 AN115 AN120 AN124 AN133 AN134 AN135