1
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X9408
Low Noise/Low Power/2-Wire Bus
Quad Digitally Controlled (XDCP™)
Potentiometers
Description
The X9408 integrates four digitally controlled potentiometers
(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 2-wire bus interface. Each
potentiometer has associated with it a volatile Wiper Counter
Register (WCR) and 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. Power-up 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.
Features
• Four Potentiometers in One Package
• 64 Resistor Taps per Potentiometer
• 2-wire Serial Interface
• Wiper Resistance, 40Ω Typical at 5V
• Four Nonvolatile Data Registers for Each Pot
• Nonvolatile Storage of Wiper Position
• Standby Current < 1µA max (Total Package)
•V
CC
= 2.7V to 5.5V Operation
V+ = 2.7V to 5.5V
V- = -2.7V to -5.5V
•10kΩ, 2.5kΩ End to End Resistances
• High reliability
• Endurance–100,000 Data Changes Per Bit Per Register
• Register Data Retention–100 years
• 24 Ld SOIC, 24 Ld TSSOP, 24 Ld PDIP Packages
• Pb-Free (RoHS Compliant)
Block Diagram
INTERFACE
AND
CONTROL
CIRCUITRY
SCL
SDA
A0
A1
A2
A3
R0 R1
R2 R3
WIPER
COUNTER
REGISTER
(WCR)
RESISTOR
ARRAY
POT 1
V
H1
/R
H1
V
L1
/R
L1
R0 R1
R2 R3
WIPER
COUNTER
REGISTER
(WCR)
V
H0
/R
H0
V
L0
/R
L0
DATA
8
V
W0
/R
W0
V
W1
/R
W1
R0 R1
R2 R3
RESISTOR
ARRAY
V
H2
/R
H2
V
L2
/R
L2
V
W2
/R
W2
R0 R1
R2 R3
RESISTOR
ARRAY
V
H3
/R
H3
V
L3
/R
L3
V
W3
/R
W3
WIPER
COUNTER
REGISTER
(WCR)
WIPER
COUNTER
REGISTER
(WCR)
POT 3
POT 2
WP
POT 0
V
CC
V
SS
V+
V-
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774
| Intersil (and design) is a registered trademark of Intersil Americas Inc.
XDCP is a trademark of Intersil Americas Inc. Copyright Intersil Americas Inc. 2005, 2009. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
Data Sheet FN8191.4January 15, 2009