Renesas X9221AUSZ

Overview

X9221AUSZ from Intersil is a dual digitally controlled potentiometer (XDCP™) with 64-tap resolution per channel, 2-wire I²C-compatible serial interface, nonvolatile data register storage (100,000 write cycles), and 20-lead SOIC package rated for -40°C to +85°C operation. It functions as two independent programmable resistive dividers for precision analog control in embedded calibration and sensor signal conditioning.

For engineers reviewing the X9221AUSZ datasheet, X9221AUSZ pinout, X9221AUSZ application, or X9221AUSZ equivalent, this device supports direct wiper position writes, volatile/nonvolatile register transfers, increment/decrement fine-tuning, and power-up recall from DR0-critical for repeatable analog tuning in industrial control and medical instrumentation.

Technical Context

The X9221AUSZ implements two independent 63-segment resistor arrays with decoded 6-bit Wiper Counter Registers (WCR), each mapped to VH/RH–VL/RL terminals and VW/RW wiper outputs. Each potentiometer includes four nonvolatile data registers (DR0–DR3) supporting store-and-recall of up to four wiper positions per channel.

Its 2-wire serial interface complies with standard I²C timing (fSCL ≤ 100 kHz), uses open-drain SDA with external pull-up, and supports slave addressing via A0–A3 pins. Communication includes nine instructions: Read/Write WCR, Read/Write Data Register, XFR between registers, Global XFR, and Increment/Decrement mode with real-time SCL-triggered wiper stepping.

Key Specifications

Pinout & Package

20-lead SOIC (300-mil, MDP0027) package with exposed pad not present; RoHS-compliant Pb-free plus anneal termination; JEDEC MS-013AC outline.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5242BRUZ10 and MCP42010-I/P, the X9221AUSZ uniquely delivers dual-channel operation with nonvolatile register storage in a compact 20-lead SOIC, enabling self-contained calibration without host intervention or additional memory components.

Availability

X9221AUSZ is available at Aetrix Electronics and suitable for industrial sensor calibration, medical instrumentation gain setting, and programmable power supply feedback requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for X9221AUSZ 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 U.S.-based analog and mixed-signal semiconductor company specializing in precision power management, interface, and data conversion ICs.

The X9221AUSZ belongs to Intersil's XDCP™ family of digitally controlled potentiometers, designed specifically for replacing mechanical trimmers in high-reliability industrial, medical, and test equipment where repeatable, programmable analog tuning is required.

FAQ

What is the maximum clock frequency supported by the X9221AUSZ I²C interface?

The X9221AUSZ supports a maximum SCL clock frequency of 100 kHz, as specified in its AC characteristics table. This limit ensures reliable communication timing, including tLOW ≥ 4700 ns and tHIGH ≥ 4000 ns. Exceeding 100 kHz may cause command rejection or incomplete register transfers. The X9221AUSZ does not support fast-mode (400 kHz) or high-speed I²C variants.

Does the X9221AUSZ retain wiper position after power cycling?

Yes, the X9221AUSZ retains wiper position after power cycling via automatic recall of Data Register 0 (DR0) into the volatile Wiper Counter Register (WCR) at power-up. This behavior is guaranteed when VCC ramp rate meets specifications (0.2–50 V/ms) and power-on sequencing follows recommended order (VCC first, then pot pins). The X9221AUSZ does not require host initialization to restore calibrated settings.

Can both potentiometers in the X9221AUSZ be controlled independently over the same I²C bus?

Yes, both potentiometers in the X9221AUSZ are independently controllable over the same 2-wire bus using instruction byte bits P0 (pot select) and R1–R0 (register select). Commands such as Write WCR or XFR Data Register to WCR target Pot 0 or Pot 1 explicitly. Global instructions (e.g., Global XFR) allow synchronized updates, but individual channel control remains fully decoupled.

What is the wiper resistance specification for the X9221AUSZ, and how does it affect circuit accuracy?

The X9221AUSZ specifies wiper resistance (RW) from 40 Ω to 130 Ω at ±1 mA wiper current. This on-resistance introduces a small series error in two-terminal variable resistor configurations and affects absolute linearity (±1 MI) when used as a potentiometer. For high-precision applications, designers should account for RW in total path resistance and avoid loading the wiper with impedances below 10 kΩ to minimize voltage error.

Is the X9221AUSZ RoHS compliant, and what does "Pb-free plus anneal" mean?

Yes, the X9221AUSZ is RoHS compliant under the "Pb-free plus anneal" designation. This means it uses 100% matte tin-plated terminations and Pb-free molding compounds compatible with both SnPb and lead-free soldering processes. It meets IPC/JEDEC J-STD-020 moisture sensitivity level requirements for peak reflow temperatures up to 260°C, ensuring robust assembly reliability without compromising legacy process compatibility.