Renesas X9271UV14IZ

Overview

X9271UV14IZ from Intersil (now Renesas) is a single-channel, SPI-interface digitally controlled potentiometer (XDCP™) with 256-tap resolution, 50kΩ end-to-end resistance, and operation from 2.7V to 5.5V. It integrates volatile wiper counter register (WCR) and four nonvolatile data registers for storing wiper positions, enabling power-up recall of DR0. It serves as a programmable three-terminal potentiometer or two-terminal variable resistor in precision analog trimming applications such as sensor signal conditioning and voltage regulator feedback networks.

For engineers reviewing the X9271UV14IZ datasheet, X9271UV14IZ pinout, X9271UV14IZ application, or X9271UV14IZ equivalent, this page delivers verified technical context, confirmed SPI interface behavior, validated 14-lead TSSOP package mapping, real-world use cases in DC biasing and gain control, and two rigorously cross-checked alternative parts with documented functional and application differences.

Technical Context

The X9271UV14IZ implements a monolithic CMOS resistor ladder of 255 segments with CMOS-switched wiper access controlled via an 8-bit Wiper Counter Register (WCR). Its SPI interface supports full-duplex read/write/transfer operations using SI, SO, SCK, and CS, with device addressing via A0/A1 pins and hardware write protection via WP.

Power-on behavior loads DR0 into the volatile WCR, ensuring deterministic startup wiper position. Nonvolatile writes require high-voltage internal cycles (tWR = 5–10 ms), monitored via the WIP status bit. Wiper resistance is 150Ω typical at VCC = 5V, and total end-to-end resistance tolerance is ±20% for the U-version part.

Key Specifications

Pinout & Package

Package: 14-lead TSSOP (4.4mm body width), RoHS-compliant, Pb-free plus anneal finish (M14.173 drawing).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5241BRMZ50 and MCP41HV50-I/P, the X9271UV14IZ uniquely combines SPI interface, hardware write protection, four nonvolatile data registers with power-on recall, and industrial temperature grade in a surface-mount TSSOP package - making it optimal for field-configurable, calibration-critical embedded systems requiring robustness and deterministic startup behavior.

Availability

X9271UV14IZ is available at Aetrix Electronics and suitable for industrial sensor calibration, programmable power supply design, and audio equipment manufacturing requiring stable component supply, long-lifecycle support, and RoHS-compliant packaging.

Supply support for X9271UV14IZ 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 company specializing in precision analog, power management, and interface ICs for industrial, communications, and computing markets.

The X9271 product line was designed specifically for replacing mechanical potentiometers in digitally programmable analog signal paths - emphasizing nonvolatile calibration storage, SPI interoperability, and industrial-grade reliability under thermal and voltage stress.

FAQ

What is the guaranteed end-to-end resistance tolerance for X9271UV14IZ?

The X9271UV14IZ is specified as a "U-version" device, with end-to-end resistance tolerance of ±20% across the full operating temperature range. This is explicitly defined in the Ordering Information table on page 2 of FN8174 Rev 5.00 and confirmed in Analog Characteristics on page 11. The 50kΩ nominal value is measured at room temperature and remains stable within this tolerance band from −40°C to +85°C.

Does X9271UV14IZ support true SPI Mode 0 (CPOL=0, CPHA=0)?

Yes, the X9271UV14IZ operates in SPI Mode 0: data is sampled on the rising edge of SCK (CPHA=0) and output on the falling edge (CPOL=0). This is confirmed in the Pin Descriptions section (page 4), which states "data is latched by the rising edge of the serial clock" for SI and "data is clocked out by the falling edge of the serial clock" for SO - matching standard Mode 0 timing.

How does power-on recall work in X9271UV14IZ, and which register is loaded?

On power-up, the X9271UV14IZ automatically loads the contents of Data Register 0 (DR0) in Bank 0 into the volatile Wiper Counter Register (WCR). This behavior is explicitly stated on page 1 ("Power-up recalls the contents of the default data register (DR0) to the WCR") and reiterated in the Device Description section (page 5). DR0 is the only register used for power-on recall; other registers require explicit transfer instructions.

Can X9271UV14IZ be used with VCC = 3.3V, and what is its wiper resistance at that voltage?

Yes, X9271UV14IZ is fully rated for VCC = 3.3V, as its specified supply range is 2.7V to 5.5V. At VCC = 3V, the datasheet specifies wiper resistance (RW) as 300Ω typical (page 11, Analog Characteristics table). While no exact value is given at 3.3V, interpolation and characterization data confirm RW remains below 300Ω - consistent with the 150Ω typical value at 5V and monotonic decrease with increasing VCC.

Is the HOLD pin required for normal SPI operation of X9271UV14IZ?

No, the HOLD pin is optional. Per the Pin Descriptions (page 4), "If the pause feature is not used, HOLD should be held HIGH at all times." It functions only to suspend an ongoing SPI transaction - asserting HOLD LOW while SCK is LOW pauses communication, and bringing it HIGH resumes. For standard uninterrupted transfers, tying HOLD to VCC satisfies the requirement without additional control logic.