Renesas X9258US24Z-2.7T1

Overview

X9258US24Z-2.7T1 from Intersil (now Renesas) is a quad digital potentiometer IC with 256-tap resolution per channel, dual ±2.7V to ±5.5V analog supplies, 2-wire I²C-compatible interface, 50kΩ end-to-end resistance, and nonvolatile wiper position storage. It replaces mechanical potentiometers in precision gain/offset trimming for industrial sensor signal conditioning.

For engineers reviewing the X9258US24Z-2.7T1 datasheet, X9258US24Z-2.7T1 pinout, X9258US24Z-2.7T1 application, or X9258US24Z-2.7T1 equivalent, key selection criteria include its 2.7V–5.5V VCC range, independent VH/VL rail support, hardware write-protect (WP), and four 8-bit nonvolatile data registers per potentiometer enabling multi-setpoint calibration.

Technical Context

The X9258US24Z-2.7T1 implements four independent 255-segment resistor arrays with CMOS switch-controlled wipers, each driven by an 8-bit volatile Wiper Counter Register (WCR). Wiper position is set via direct WCR write, register transfer (DR→WCR), or real-time increment/decrement using SCL clock edges while holding SDA high/low.

It operates as a slave on a 2-wire bus with configurable 4-bit device address (A0–A3), supports up to 400kHz clock frequency, and features automatic power-up recall of DR0 into each WCR. Nonvolatile writes require elevated V+ and V− rails and take 5–10ms, with ACK polling supported.

Key Specifications

Pinout & Package

24-lead SOIC (300 mil, M24.3 package) with exposed pad not present; RoHS-compliant matte tin finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5242BRUZ10 and MCP42050-I/P, the X9258US24Z-2.7T1 uniquely delivers four matched pots with true bipolar analog operation, hardware write protection, and four nonvolatile registers per channel-enabling complex multi-point calibration in compact industrial signal chains.

Availability

X9258US24Z-2.7T1 is available at Aetrix Electronics and suitable for industrial sensor calibration, programmable gain amplification, and bipolar DC bias adjustment requiring stable component supply across extended temperature and voltage ranges.

Supply support for X9258US24Z-2.7T1 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 (acquired by Renesas Electronics in 2017) is a semiconductor company specializing in high-performance analog and mixed-signal ICs for industrial, aerospace, and communications markets.

The X9258 product line was designed for precision analog trimming in harsh environments, emphasizing nonvolatile configuration retention, bipolar signal compatibility, and robust ESD tolerance in industrial automation systems.

FAQ

What is the minimum VCC voltage required for reliable operation of the X9258US24Z-2.7T1?

The X9258US24Z-2.7T1 is rated for VCC from 2.7V to 5.5V. At 2.7V, all digital logic-including I²C interface, address decoding, and register access-functions correctly per datasheet specifications. However, analog performance (e.g., wiper resistance, noise) is characterized at nominal 5V; operation at 2.7V remains functional but may exhibit slightly increased RW and reduced noise margin. The X9258US24Z-2.7T1 maintains full feature set including nonvolatile writes and power-up recall down to 2.7V.

Can the X9258US24Z-2.7T1 operate with only a single positive supply, or does it require both V+ and V−?

The X9258US24Z-2.7T1 requires both V+ and V− analog supplies to bias its resistor arrays. These rails define the voltage range across each potentiometer's VH and VL terminals. While V+ can be tied to VCC and V− to GND for unipolar 0–VCC operation, the device is explicitly designed for true bipolar use: V+ ≥ +2.7V and V− ≤ −2.7V. Omitting either rail violates absolute maximum ratings and prevents proper wiper switching. The X9258US24Z-2.7T1 cannot function with only one analog supply.

How many unique wiper positions does each potentiometer in the X9258US24Z-2.7T1 support?

Each of the four potentiometers in the X9258US24Z-2.7T1 supports exactly 256 discrete wiper positions, corresponding to 0x00 through 0xFF in the 8-bit Wiper Counter Register. This is achieved via 255 resistive elements arranged in series, with tap points between each element connected to the wiper through CMOS switches. The 256-step resolution yields 0.4% step size relative to full-scale resistance. The X9258US24Z-2.7T1 does not interpolate between taps; position is strictly quantized.

Does the X9258US24Z-2.7T1 retain wiper settings after power cycling?

Yes-the X9258US24Z-2.7T1 retains wiper position across power cycles by loading Data Register 0 (DR0) into each Wiper Counter Register (WCR) at power-up. DR0 is nonvolatile and retains data for 100 years. To preserve a specific setting, write it to DR0 (via Write Data Register instruction), then execute XFR Data Register to Wiper Counter Register. Subsequent power cycles will restore that value. Volatile WCR contents alone are lost on power-down; only DR0 auto-loads. The X9258US24Z-2.7T1 thus guarantees deterministic startup behavior when DR0 is pre-programmed.

What is the purpose of the WP pin on the X9258US24Z-2.7T1, and how should it be used?

The WP (Write Protect) pin on the X9258US24Z-2.7T1 is an active-low hardware lock that disables all nonvolatile writes to the Data Registers when pulled low. While WP is low, commands like Write Data Register or XFR WCR to DR are ignored-preventing accidental EEPROM corruption during firmware updates, ESD events, or power transients. For normal operation, WP should be tied to VCC (inactive) or controlled by a system supervisor. The X9258US24Z-2.7T1 ignores WP state for volatile WCR writes, allowing runtime adjustment even when nonvolatile storage is locked.