Renesas X9421WV14I-2.7

Overview

X9421WV14I-2.7 from Intersil is a single-channel, digitally controlled potentiometer (XDCP™) with 64-tap resistor array, SPI interface, 2.5kΩ end-to-end resistance, -40°C to +85°C operating temperature, and 2.7V–5.5V supply range. It functions as a programmable three-terminal potentiometer or two-terminal variable resistor for precision analog trimming in sensor signal conditioning, voltage regulator feedback, and audio gain control.

For engineers reviewing the X9421WV14I-2.7 datasheet, X9421WV14I-2.7 pinout, X9421WV14I-2.7 application, or X9421WV14I-2.7 equivalent, key selection criteria include wiper position recall on power-up, nonvolatile storage of four independent settings, low 150Ω typical wiper resistance at 5V, <5µA standby current, and compatibility with standard SPI bus timing (2MHz max clock).

Technical Context

The X9421WV14I-2.7 implements a monolithic CMOS 63-segment resistor ladder with CMOS switch-controlled wiper positioning. Its volatile Wiper Counter Register (WCR) directly controls tap selection, while four 6-bit nonvolatile Data Registers (DR0–DR3) store persistent wiper positions or system parameters.

Power-on behavior loads DR0 into the WCR, enabling deterministic startup. All nonvolatile writes require hardware write protect (WP) deactivation and complete within 10ms, with status monitored via the WIP bit. The device supports full-duplex SPI communication with CS, SCK, SI, SO, HOLD, A0, and WP control signals.

Key Specifications

Pinout & Package

Package: 14-lead TSSOP (4.4mm body width), RoHS-compliant, Pb-free termination.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ISL22416 and ISL22419, the X9421WV14I-2.7 delivers guaranteed power-on wiper position restoration, SPI-native operation with HOLD capability, and compact 14-pin TSSOP packaging-making it optimal for industrial control, sensor calibration, and legacy SPI-based embedded systems requiring deterministic analog trimming.

Availability

X9421WV14I-2.7 is available at Aetrix Electronics and suitable for industrial sensor calibration, programmable power supply design, and audio equipment manufacturing requiring stable component supply and long-term obsolescence management.

Supply support for X9421WV14I-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 Corporation, now part of Renesas Electronics, designs high-performance analog and mixed-signal ICs for power management, precision analog, and interface applications.

The X9421 product line delivers digitally controlled potentiometers optimized for replacing mechanical trimmers in industrial, medical, and communications equipment where reliability, programmability, and nonvolatile calibration storage are essential.

FAQ

What is the default wiper position after power-up for the X9421WV14I-2.7?

Upon power-up, the X9421WV14I-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 behavior occurs once VCC stabilizes and requires no host intervention, ensuring repeatable startup conditions. The DR0 value must be pre-programmed during manufacturing or field calibration to define the desired default setting for the X9421WV14I-2.7.

Can the X9421WV14I-2.7 operate from a 3.3V supply?

Yes, the X9421WV14I-2.7 supports a supply voltage range of 2.7V to 5.5V, making it fully compatible with standard 3.3V logic systems. At 3.3V, its wiper resistance increases to 400Ω typical (vs. 150Ω at 5V), and standby current remains below 5µA. All SPI timing specifications-including 2MHz maximum clock frequency-are maintained across this voltage range, ensuring reliable operation in mixed-voltage embedded designs using the X9421WV14I-2.7.

How many independent wiper settings can be stored in the X9421WV14I-2.7?

The X9421WV14I-2.7 contains four 6-bit nonvolatile Data Registers (DR0–DR3), each capable of storing one independent wiper position. These registers retain their values for up to 100 years and support 100,000 write cycles per bit. Users may load any stored value into the volatile Wiper Counter Register via the XFR instruction, enabling rapid switching between calibrated configurations-for example, factory trim, user-adjusted min/max, or temperature-compensated settings-without reprogramming the X9421WV14I-2.7.

Is hardware write protection mandatory for normal operation of the X9421WV14I-2.7?

No, hardware write protection is optional. The WP pin must be held HIGH to allow writes to the nonvolatile Data Registers; pulling WP LOW disables DR writes but permits unrestricted updates to the volatile Wiper Counter Register (WCR). This enables safe runtime adjustment of the wiper position while preserving factory-stored calibration data. For applications requiring permanent DR locking, WP should be tied to VCC; for field recalibration, WP can be controlled by a microcontroller GPIO to selectively enable nonvolatile writes when needed for the X9421WV14I-2.7.

Does the X9421WV14I-2.7 support daisy-chained SPI connections?

The X9421WV14I-2.7 does not support true daisy-chaining due to its dedicated SO output and lack of cascaded data path. However, its SO and SI pins are three-state capable and can be wired in parallel (SO/SI tied together) with proper bus arbitration, reducing pin count on microcontrollers. Multi-device operation is supported via individual CS lines-one per X9421WV14I-2.7-with A0 addressing enabling up to two devices on a shared SPI bus. This configuration maintains full independent control without modifying the X9421WV14I-2.7's native interface protocol.