Renesas X9318WS8IZ

Overview

X9318WS8IZ from Intersil is a digitally controlled potentiometer (XDCP™) implementing a 10 kΩ end-to-end resistance with 100 wiper tap points, nonvolatile wiper position storage, and 3-wire serial interface (CS/U/D/INC). It operates from 4.5–5.5 V, supports terminal voltages up to +8 V, and delivers ±1% absolute linearity over –40°C to +85°C for precision analog trimming in voltage regulator feedback paths.

For engineers reviewing the X9318WS8IZ datasheet, X9318WS8IZ pinout, X9318WS8IZ application, or X9318WS8IZ equivalent, this device serves as a solid-state replacement for mechanical potentiometers where repeatable, drift-free, and programmable resistance adjustment is required-especially in LCD bias control, laser diode current setting, and DC offset trim circuits demanding long-term data retention and low power consumption.

Technical Context

The X9318WS8IZ integrates a 99-element resistor array with "make-before-break" electronic wiper switching, a 7-bit up/down counter, and nonvolatile memory for wiper position recall on power-up. Its control logic responds to CS-select, U/D direction, and negative-edge-triggered INC pulses-enabling deterministic wiper movement without microcontroller firmware overhead.

It features temperature-compensated resistive elements (±300 ppm/°C RTOTAL TC), ratiometric tracking (±20 ppm/°C), and wiper resistance of 40 Ω typical. The device enters standby mode (<1 mA) when CS is high and supports store-on-CS-high-with-INC-high operation for reliable nonvolatile updates.

Key Specifications

Pinout & Package

8-lead SOIC (150 mil width), RoHS-compliant Pb-free plus anneal finish, rated for –40°C to +85°C industrial temperature range.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5243BRMZ10 and MCP41010-I/P, the X9318WS8IZ provides simpler 3-wire control, guaranteed nonvolatile retention without host intervention, and optimized endurance for infrequent but mission-critical trim adjustments-making it ideal for unattended embedded systems requiring long-term calibration stability.

Availability

X9318WS8IZ is available at Aetrix Electronics and suitable for LCD bias control, laser diode biasing, and voltage regulator output trimming requiring stable component supply, long-term calibration integrity, and industrial temperature operation.

Supply support for X9318WS8IZ 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

Intersil Corporation (now part of Renesas Electronics) is a semiconductor design and manufacturing company specializing in precision analog, power management, and interface ICs for industrial, computing, and communications markets.

The X9318WS8IZ belongs to Intersil's XDCP™ (Digitally Controlled Potentiometer) family, engineered for replacing mechanical trimmers in applications demanding programmability, reliability, and nonvolatile setting retention without microcontroller dependency.

FAQ

What is the operating temperature range for the X9318WS8IZ?

The X9318WS8IZ is rated for –40°C to +85°C, matching industrial-grade requirements. This range is confirmed in the ordering information table of the FN8184 datasheet, where "X9318WS8IZ" explicitly lists "–40 to 85" under TEMP RANGE. All electrical specifications-including linearity, RTOTAL tolerance, and endurance-are guaranteed across this full range.

Does the X9318WS8IZ require an external clock or data line for communication?

No, the X9318WS8IZ uses a self-contained 3-wire serial interface with only CS, U/D, and INC signals-no clock or bidirectional data line is needed. The INC input is negative-edge-triggered, and U/D sets direction; timing parameters like tCYC (4 µs min) and tIW (100–500 µs wiper settling) are defined in the AC Operating Characteristics table of the datasheet.

How is wiper position stored and recalled in the X9318WS8IZ?

Wiper position is stored in nonvolatile memory when CS transitions HIGH while INC is held HIGH; it is automatically recalled on power-up. This behavior is documented in the "PRINCIPLES OF OPERATION" and "INSTRUCTIONS AND PROGRAMMING" sections of FN8184. The device retains settings for 100 years and withstands 100,000 store cycles per bit.

Can the X9318WS8IZ be used as a two-terminal variable resistor?

Yes, the X9318WS8IZ supports both three-terminal potentiometer (RH–RW–RL) and two-terminal variable resistor (e.g., RW–RL or RW–RH) configurations. The datasheet states: "The device can be used as a three-terminal potentiometer for voltage control or as a two-terminal variable resistor for current control," with wiper resistance specified at 40 Ω typical and terminal voltage limits applying to RH/RL/RW individually.

What is the maximum allowable voltage on RH, RL, and RW terminals of the X9318WS8IZ?

The absolute maximum voltage on RH, RL, and RW is +10 V with respect to VSS, per the Absolute Maximum Ratings table. However, the recommended operating range is 0 to +8 V, as specified under "VRH/RL" in the Potentiometer Characteristics table. Exceeding +8 V may degrade long-term reliability despite surviving short-term stress.