Renesas X9401WP24I-2.7

Overview

X9401WP24I-2.7 from Intersil is a quad-channel, 64-tap digitally controlled potentiometer (XDCP™) with SPI interface, 10 kΩ end-to-end resistance, 150 Ω typical wiper resistance, and 2.7 V to 5.5 V supply operation - used for precision voltage division and programmable gain control in analog signal conditioning circuits.

For engineers reviewing the X9401WP24I-2.7 datasheet, X9401WP24I-2.7 pinout, X9401WP24I-2.7 application, or X9401WP24I-2.7 equivalent, key selection criteria include nonvolatile wiper position storage, four independent 6-bit data registers per pot, <3 µA standby current, SPI-compatible timing at up to 2 MHz, and SOIC-24 package compatibility with industrial temperature range (–40°C to +85°C).

Technical Context

The X9401WP24I-2.7 implements four independent resistor arrays, each with 63 discrete segments and 64 tap points controlled by a volatile 6-bit Wiper Counter Register (WCR). Each potentiometer supports direct SPI write/read of its WCR and four nonvolatile 6-bit Data Registers (DR0–DR3), enabling persistent wiper state recall on power-up from DR0.

Its SPI interface complies with standard mode-0 (CPOL=0, CPHA=0) timing, uses CS-active-low selection with HOLD for serial pause, and supports hardware write protection via the WP pin. The device operates across full 2.7 V to 5.5 V VCC range with guaranteed 2 MHz SCK frequency and 10 µs wiper response time after load instructions.

Key Specifications

Pinout & Package

Package: 24-lead SOIC (300 mil, Pb-free, M24.3 drawing), industrial temperature grade (–40°C to +85°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5204BRUZ10 and MCP42010-I/P, the X9401WP24I-2.7 uniquely combines quad-channel density, true 2.7 V SPI operation, hardware write protection, and HOLD support - making it optimal for industrial analog reconfiguration where reliability, channel count, and low-voltage flexibility are jointly critical.

Availability

X9401WP24I-2.7 is available at Aetrix Electronics and suitable for industrial sensor calibration, programmable power supplies, and embedded audio systems requiring stable component supply across extended lifecycle programs.

Supply support for X9401WP24I-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 is a provider of precision analog and power management ICs, now part of Renesas Electronics, with focus on high-reliability industrial and infrastructure solutions.

The X9401 product line was designed for digitally reconfigurable analog signal paths in systems requiring nonvolatile parameter storage, low-power operation, and robust serial control - especially where mechanical potentiometers fail due to wear or environmental stress.

FAQ

What is the minimum VCC voltage supported by the X9401WP24I-2.7?

The X9401WP24I-2.7 supports a minimum VCC of 2.7 V, as specified in the Absolute Maximum Ratings table. This allows direct interfacing with 3.3 V microcontrollers and battery-powered systems down to single-cell Li-ion or alkaline levels. Operation below 2.7 V may result in undefined behavior or failure to retain nonvolatile register contents. The X9401WP24I-2.7 maintains full SPI functionality and wiper positioning accuracy across the entire 2.7 V to 5.5 V range.

How does the hardware write protect (WP) pin function on the X9401WP24I-2.7?

When the WP pin on the X9401WP24I-2.7 is driven LOW, all nonvolatile write operations - including transfers from Wiper Counter Register to Data Registers and direct Data Register writes - are disabled. This prevents accidental corruption of stored calibration values during firmware updates or noise events. The WP pin has no effect on volatile WCR writes or SPI reads. For reliable protection, WP should be tied to VSS or actively controlled by the host MCU; leaving it floating is not recommended.

Can the X9401WP24I-2.7 be used as a two-terminal variable resistor?

Yes, the X9401WP24I-2.7 can operate as a two-terminal variable resistor by connecting either VH or VL to the wiper VW (e.g., shorting VH0 to VW0), effectively using only one half of the resistor array. This configuration achieves a 0–10 kΩ adjustable resistance with 64 discrete steps. The wiper resistance (150 Ω typical) becomes part of the total resistance path, so minimum resistance is not zero. This mode is commonly used in current-limiting or bias-setting applications where three-terminal voltage division is unnecessary.

What is the purpose of the HOLD pin on the X9401WP24I-2.7?

The HOLD pin on the X9401WP24I-2.7 allows pausing an ongoing SPI transaction without resetting the internal command state. When asserted LOW while SCK is LOW, it freezes serial communication mid-sequence; bringing HOLD HIGH (with SCK still LOW) resumes exactly where it left off. This feature is essential in multi-interrupt systems where the host MCU must service higher-priority tasks without aborting potentiometer configuration. It eliminates the need to reinitialize the SPI frame or resend address bytes upon resumption.

Does the X9401WP24I-2.7 support daisy-chaining multiple devices on one SPI bus?

No, the X9401WP24I-2.7 does not support daisy-chaining. It uses a standard SPI slave architecture with individual CS lines - meaning each device requires its own dedicated chip select signal. However, up to four X9401WP24I-2.7 units can share the same SCK, SI, and SO lines by assigning unique addresses via A0/A1 pins and using separate CS signals. This parallel topology preserves full bandwidth per device and avoids timing skew inherent in daisy-chain configurations.