ISL22317
Precision Single Digitally Controlled Potentiometer (XDCP™) Low Noise, Low Power, I2C™ Bus, 128 Taps
Key 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 100kΩ Total 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)
Description
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.
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
