DESCRIPTION
The X9250 integrates 4 digitally controlled
potentiometers (XDCP) on a monolithic CMOS
integrated circuit.
The digitally controlled potentiometer is implemented
using 255 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. 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 though 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.

FEATURES
• Four potentiometers in one package
• 256 resistor taps/pot - 0.4% resolution
• SPI serial interface
• Wiper resistance, 40Ω typical @ VCC = 5V
• Four nonvolatile data registers for each pot
• Nonvolatile storage of wiper position
• Standby current < 5µA max (total package)
• Power supplies
—VCC = 2.7V to 5.5V
—V+ = 2.7V to 5.5V
—V– = -2.7V to -5.5V
• 100kΩ, 50kΩ total pot resistance
• High reliability
—Endurance – 100,000 data changes per bit per
register
—Register data retention - 100 years
• 24 Ld SOIC, 24 Ld TSSOP
• Dual supply version of X9251
• Pb-free plus anneal available (RoHS compliant)