APPLICATION NOTES AND DEVELOPMENT SYSTEM
A V A I L A B L E
AN20 • AN42–48 • AN50–53 • AN73 • XK9241
TXe9r2m41inal Voltage ±5V, 64 Taps
X9241
Quad E2POT™ Nonvolatile Digital Potentiometer
FEATURES
DESCRIPTION
2
2
• Four E POTs in One Package
• Two-Wire Serial Interface
• Register Oriented Format
—Directly Write Wiper Position
—Read Wiper Position
The X9241 integrates four nonvolatile E POT digitally
controlled potentiometers on a monolithic CMOS micro-
circuit.
The X9241 contains four resistor arrays, each com-
posed of 63 resistive elements. Between each element
and at either end are tap points accessible to the wiper
elements. The position of the wiper element on the array
is controlled by the user through the two-wire serial bus
interface.
—Store as Many as Four Positions per Pot
• Instruction Format
—Quick Transfer of Register Contents to
Resistor Array
—Cascade Resistor Arrays
• Low Power CMOS
Eachresistorarrayhasassociatedwithitawipercounter
register and four 8-bit data registers that can be directly
written and read by the user. The contents of the wiper
counter register control the position of the wiper on the
resistor array.
• Direct Write Cell
—Endurance - 100,000 Data Changes per Register
—Register Data Retention - 100 years
2
• 16 Bytes of E PROM 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
Thedataregistermaybereadorwrittenbytheuser. The
contents of the data registers can be transferred to the
wiper counter register to position the wiper. The current
wiper position can be transferred to any one of its
associated data registers.
The arrays may be cascaded to form resistive elements
with 127, 190 or 253 taps.
FUNCTIONAL DIAGRAM
VH2
R0 R1
WIPER
R0 R1
R2 R3
VH0
WIPER
COUNTER
REGISTER
(WCR)
RESISTOR
ARRAY
POT 2
COUNTER
REGISTER
VL2
VW2
(WCR)
VL0
VW0
R2 R3
SCL
SDA
A0
A1
INTERFACE
AND
CONTROL
CIRCUITRY
8
A2
A3
DATA
VH1
VH3
R0 R1
R2 R3
R0 R1
R2 R3
WIPER
COUNTER
REGISTER
(WCR)
WIPER
COUNTER
REGISTER
(WCR)
RESISTOR
ARRAY
POT 3
RESISTOR
ARRAY
POT 1
VL1
VW1
VL3
VW3
3864 ILL F07.1
© Xicor, Inc. 1994, 1995, 1996 Patents Pending
3864-2.7 7/1/96 T0/C3/D3 NS
Characteristics subject to change without notice
1