The digitally controlled potentiometer is implemented with a
combination of resistor elements and CMOS switches. The
position of the wiper is controlled by the user through the I2C
bus interface. The potentiometer has an associated volatile
Wiper Register (WR) and a non-volatile Initial Value Register
(IVR) that can be directly written to and read by the user. The
contents of the WR control the position of the wiper. At
power up, the device recalls the contents of the DCP’s IVR
to the WR.
The highly precise ISL22317 features a low end-to-end
temperature coefficient of TC_Ref ±10ppm/°C and precise
resistance selection. It maintains less than ±1% typical
variance from the ideal resistance at each wiper position
providing 99% accuracy of selected resistance value. This
highly accurate DCP eliminates the need for complex
algorithms to guarantee precision. The ISL22317 allows the
user to dial in an accurate resistance and the EEPROM
memory stores the set value for life, or until changed by the
user.
An external 0.5% or better reference resistor must be
attached to the ISL22317. The ISL22317 will mirror both the
precise resistance and temperature coefficient of the
external resistor.
The DCP 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
• Precision Digitally Controlled Potentiometer
- 99% Typical Accuracy Of Resistance Over Operational
Conditions
- Zero-Compensated Wiper Resistance
• Integrated Digitally Controlled Potentiometer
- 128-Tap Positions
- I2C Serial Interface
- Pin Selectable Slave Address
- 10kΩ, 50kΩ and 100kΩTotal Resistance
- Monotonic Over-Temperature
- Non-Volatile EEPROM Storage of Wiper Position
- 0 to VCC Terminal Voltage
• Single 2.7V to 5.5V Supply
• High Reliability
- 50 Years Retention @ ≤ +55°C
- 15 Years Retention @ +125°C
- 1,000,000 Cycles Endurance
• 3mmx3mm Thin DFN Package – 0.75mm Max Thickness,
0.65mm Pitch
• Pb-Free (RoHS Compliant)

Applications
• Setting Precise Current Values for DC Margining and
Backlight Control
• Replaces Complex Compensation Circuitry That Stores
Values in Look-up Tables Needed for Precise Resistor
Setting
• Setting Precise Resistance Values for Test and
Measurement Circuits
• Adjust Specific Resistances in Analog Circuits
• Precise Calibration and Fine Tune-Up