X9241A Datasheet, PDF (1/18 Pages) Xicor Inc. – Quad Digitally Controlled Potentiometer (XDCP)

APPLICATION NOTE
AVAILABLE
AN20 • AN42–48 • AN50-53 • AN73 • AN99 • AN115 • AN120 • AN124 • AN133 • AN134 • AN135
Low Power/2-Wire Serial Bus
X9241A
Quad Digitally Controlled Potentiometer (XDCP^™)
FEATURES
• Four potentiometers in one package
• 2-wire serial interface
• Register oriented format
—Direct read/write/transfer of wiper positions
—Store as many as four positions per
potentiometer
• Terminal Voltages: +5V, -3.0V
• Cascade resistor arrays
• Low power CMOS
• High Reliability
—Endurance–100,000 data changes per bit per
register
—Register data retention–100 years
• 16-bytes of nonvolatile memory
• 3 resistor array values
—2KΩ to 50KΩ mask programmable
—Cascadable for values of 500Ω to 200KΩ
• Resolution: 64 taps each pot
• 20-lead plastic DIP, 20-lead TSSOP and 20-lead
SOIC packages
DESCRIPTION
The X9241A integrates four digitally controlled
potentiometers (XDCP) on a monolithic CMOS
integrated microcircuit.
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
V_CC
V_SS
SCL
SDA
A0
A1
A2
A3
Interface
and
Control
Circuitry
8
Data
R0 R1
R2 R3
Wiper
Counter
Register
(WCR)
V_H0/R_H0
V_L0/R_L0
V_W0/R_W0
R0 R1
R2 R3
Wiper
Counter
Register
(WCR)
Register
Array
Pot 2
V_H2/
R_H2
V_L2/R_L2
V_W2/R_W2
R0 R1
R2 R3
Wiper
Counter
Register
(WCR)
Register
Array
Pot 1
V_H1/R_H1
V_L1/R_L1
V_W1/R_W1
R0 R1
R2 R3
Wiper
Counter
Register
(WCR)
Register
Array
Pot 3
V_H3/R_H3
V_L3/R_L3
V_W3/R_W3
REV 1.1.13 12/09/02
www.xicor.com
Characteristics subject to change without notice. 1 of 18