Renesas X9271UV14I-2.7

Overview

X9271UV14I-2.7 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.

For engineers reviewing the X9271UV14I-2.7 datasheet, X9271UV14I-2.7 pinout, X9271UV14I-2.7 application, or X9271UV14I-2.7 equivalent, this device supports SPI write/read/transfer operations, offers <3µA standby current, features hardware write protection (WP), and provides 100-year data retention - critical for industrial sensor calibration, DC bias control, and embedded system parameter tuning where nonvolatile setting persistence is required.

Technical Context

The X9271UV14I-2.7 implements a monolithic CMOS resistor ladder of 255 segments with CMOS-switched wiper taps controlled by an 8-bit Wiper Counter Register (WCR). Its SPI interface complies with standard serial clock (SCK), chip select (CS), serial input (SI), and serial output (SO) timing, supporting up to 2.5MHz clock frequency and full-duplex read/write/transfer instructions.

Power-on behavior loads DR0 into the volatile WCR; nonvolatile writes to data registers require high-voltage internal cycles (tWR = 5–10ms). The device supports dual address pins (A0/A1) for multi-device SPI bus configuration, HOLD for communication pause, and hardware write protect (WP) to prevent unintended register updates.

Key Specifications

Pinout & Package

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

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5241BRMZ50 and MCP41050-I/P, the X9271UV14I-2.7 uniquely combines SPI+HOLD+WP functionality, four nonvolatile data registers, and power-on DR0 recall - making it optimal for industrial systems requiring robust, field-serviceable analog calibration with fail-safe write control.

Availability

X9271UV14I-2.7 is available at Aetrix Electronics and suitable for industrial sensor calibration, embedded DC bias control, and programmable power supply feedback requiring stable component supply across extended temperature ranges (-40°C to +85°C).

Supply support for X9271UV14I-2.7 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 power management, precision analog, and interface applications.

The X9271UV14I-2.7 belongs to Intersil's XDCP™ (eXternally Digitally Controlled Potentiometer) family, designed specifically for replacing mechanical potentiometers in automated calibration, closed-loop control, and programmable analog signal conditioning systems.

FAQ

What is the supply voltage range supported by the X9271UV14I-2.7?

The X9271UV14I-2.7 operates from 2.7V to 5.5V, making it compatible with both 3.3V and 5V logic systems. This wide range eliminates the need for external level shifters and supports direct integration into mixed-voltage designs. The device maintains full functionality-including SPI communication, wiper positioning, and nonvolatile register access-across the entire specified voltage window. Absolute maximum VCC is 7V, but operation outside 2.7–5.5V voids guaranteed performance per datasheet specifications.

How does power-up behavior work in the X9271UV14I-2.7?

On power-up, the X9271UV14I-2.7 automatically loads the contents of Data Register 0 (DR0) into the volatile Wiper Counter Register (WCR), establishing the initial wiper position. This recall function occurs after VCC stabilizes and requires no host intervention. DR0 must be pre-programmed during manufacturing or field calibration; if unmodified, it defaults to 0x00 (wiper at RL). The behavior is independent of CS or SPI activity and ensures repeatable startup conditions for safety-critical or self-calibrating systems.

Can the X9271UV14I-2.7 be used as a two-terminal variable resistor?

Yes, the X9271UV14I-2.7 can operate as a two-terminal variable resistor by connecting either RH or RL to RW (e.g., short RH to RW for a rheostat between RL and RW). In this mode, resistance varies from near 0Ω (WCR = 0x00 or 0xFF) to 50kΩ (WCR = mid-scale), with wiper resistance (150Ω typ.) contributing to minimum on-resistance. The datasheet explicitly confirms this configuration for applications like LED current limiting and gain-setting networks where three-terminal operation is unnecessary.

What is the purpose of the HOLD pin on the X9271UV14I-2.7?

The HOLD pin on the X9271UV14I-2.7 allows pausing an ongoing SPI transaction without resetting the command sequence. When asserted LOW while SCK is LOW, it suspends communication; returning HOLD HIGH (with SCK still LOW) resumes from the exact point of interruption. This feature prevents bus contention in multi-master environments and enables priority interrupt handling in microcontroller systems. If unused, HOLD must be tied HIGH to avoid unintended pauses.

Does the X9271UV14I-2.7 support multiple devices on the same SPI bus?

Yes, the X9271UV14I-2.7 supports up to four devices on a shared SPI bus using its dual address pins A0 and A1. These pins configure a 2-bit slave address (00 to 11), allowing individual selection via the ID byte in SPI commands. Each device responds only when its physical A0/A1 state matches the incoming address bits. This enables compact, scalable designs-for example, simultaneous calibration of multiple sensor channels-without additional chip-select lines.