Renesas ISL22317UFRTZ-TK

Overview

ISL22317UFRTZ-TK from Renesas Electronics (formerly Intersil) is a precision digitally controlled potentiometer (XDCP™) with I²C interface, 128-tap resolution, 50kΩ end-to-end resistance, ±10ppm/°C ratiometric temperature coefficient matched to external reference, and non-volatile EEPROM storage. It operates from 2.7V to 5.5V and delivers 99% typical resistance accuracy across temperature for high-stability analog trimming in DC margining and backlight control circuits.

For engineers reviewing the ISL22317UFRTZ-TK datasheet, ISL22317UFRTZ-TK pinout, ISL22317UFRTZ-TK application, or ISL22317UFRTZ-TK equivalent, this device supports voltage divider and rheostat modes, features zero-compensated wiper resistance, monotonic operation over -40°C to +125°C, and integrates volatile Wiper Register (WR) and non-volatile Initial Value Register (IVR) for power-up recall.

Technical Context

The ISL22317UFRTZ-TK implements a resistor ladder with CMOS switches in a "make-before-break" switching architecture, enabling glitch-free wiper transitions. Its precision mode mirrors both resistance value and temperature coefficient of an external 0.5% reference resistor connected between REF_A and REF_B.

It supports two operational modes via Mode Select Register: Voltage Divider Mode (RH–RL–RW) with ratiometric tracking, and Rheostat Mode (RW–RL only, RH floating), with programmable shutdown and I²C slave address selection via A1 pin. The device recalls IVR to WR at power-up after V_POR ≥ 2.6V.

Key Specifications

Pinout & Package

ISL22317UFRTZ-TK uses a 10-lead 3mm × 3mm Thin DFN (TDFN) package with 0.65mm pitch and 0.75mm max height. Exposed pad internally connected to GND.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digitally controlled potentiometer applications.

Compared with AD5175BRMZ-50 and MCP45HV51-503E/MS, the ISL22317UFRTZ-TK uniquely delivers ±10ppm/°C ratiometric TC tracking to an external reference and guaranteed 99% resistance accuracy - making it optimal for metrology-grade trimming where long-term drift and temperature-induced error must be minimized.

Availability

ISL22317UFRTZ-TK is available at Aetrix Electronics and suitable for DC margining, backlight control, and test equipment calibration requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for ISL22317UFRTZ-TK includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Renesas Electronics acquired Intersil in 2017 and maintains its precision analog portfolio, emphasizing high-reliability, temperature-stable components for industrial and automotive applications.

The ISL22317UFRTZ-TK belongs to Renesas' XDCP™ (eXternally Defined Controlled Potentiometer) family, designed specifically for applications demanding traceable resistance accuracy, non-volatile configuration retention, and ratiometric temperature stability without software calibration.

FAQ

What is the total resistance value of the ISL22317UFRTZ-TK?

The ISL22317UFRTZ-TK has a nominal end-to-end resistance of 50kΩ. This value is precisely matched to an external 50kΩ ±0.5% reference resistor connected between REF_A and REF_B in precision mode. Without the external reference, the device operates as a standard DCP with ~40% higher resistance and reduced accuracy.

How does the ISL22317UFRTZ-TK achieve ±10ppm/°C temperature coefficient?

The ISL22317UFRTZ-TK achieves ±10ppm/°C ratiometric temperature coefficient by mirroring both the resistance value and temperature behavior of the external reference resistor. Its internal circuitry tracks the reference's TC, ensuring the DCP's RH–RL resistance changes identically with temperature - a feature confirmed in Analog Specifications Table on page 3 of FN6912 Rev 1.00.

Can the ISL22317UFRTZ-TK operate in rheostat mode, and how is it configured?

Yes, the ISL22317UFRTZ-TK supports rheostat mode via the Mode Select Register (MSR). Setting MSR<7> = 0 configures the device as a two-terminal variable resistor between RW and RL, with RH left unconnected. This mode is validated in the "Principles of Operation" section (page 11) and used in applications like LED current adjustment.

What is the purpose of the REF_A and REF_B pins on the ISL22317UFRTZ-TK?

REF_A and REF_B provide connection points for an external 50kΩ ±0.5% reference resistor. The ISL22317UFRTZ-TK uses this resistor to calibrate its internal ladder, achieving 99% resistance accuracy and ±10ppm/°C ratiometric TC. REF_A must never be connected to GND - doing so may damage the ISL22317UFRTZ-TK, as explicitly warned in the Pin Description section (page 10).

Does the ISL22317UFRTZ-TK retain its wiper setting after power cycling?

Yes. The ISL22317UFRTZ-TK stores the wiper position in a non-volatile Initial Value Register (IVR) with 50-year retention at ≤+55°C. At power-up, the device automatically recalls the IVR contents into the volatile Wiper Register (WR), restoring the last programmed resistance value - a behavior documented in the "Principles of Operation" and "Memory Description" sections (pages 11–12).