鈩?/div>
End to End Resistance
鈥?100 yr. Data Retention
鈥?Endurance: 100, 000 Data Changes per Bit per
Register
鈥?14-Lead TSSOP, 16-Lead SOIC
鈥?Low Power CMOS
DESCRIPTION
The X9421 integrates a single digitally controlled
potentiometer (XDCP) on a monolithic CMOS
integrated circuit.
The digital 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 SPI bus
interface. The potentiometer has associated with it a
volatile Wiper Counter Register (WCR) and a four non-
volatile Data Registers 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
though the switches. Powerup recalls the contents of
the default data register (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
V
CC
R
H
/V
H
address
data
status
SPI
bus
interface
write
read
transfer
inc / dec
Bus
Interface &
Control
Power On Recall
Wiper Counter
Register (WCR)
wiper
POT
10K鈩?/div>
64-taps
control
Data Registers
4 Bytes
V
SS
R
W
/V
W
R
L
/V
L
REV 1.1.6 8/1/02
www.xicor.com
Characteristics subject to change without notice.
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