Renesas X9401WS24IZ-2.7T1

Overview

X9401WS24IZ-2.7T1 from Intersil is a quad digitally controlled potentiometer (XDCP™) with 64-tap resistor arrays per channel, SPI serial interface, 10 kΩ end-to-end resistance, 2.7 V to 5.5 V supply range, and nonvolatile wiper position storage-used for precision analog trimming in programmable power supplies and sensor calibration circuits.

For engineers reviewing the X9401WS24IZ-2.7T1 datasheet, X9401WS24IZ-2.7T1 pinout, X9401WS24IZ-2.7T1 application, or X9401WS24IZ-2.7T1 equivalent, key selection criteria include SPI-compatible 24-pin SOIC packaging, 150 Ω typical wiper resistance, <3 µA standby current, 100-year data retention, and hardware write protection via WP pin.

Technical Context

The X9401WS24IZ-2.7T1 implements four independent 64-element CMOS resistor arrays, each controlled by a volatile 6-bit Wiper Counter Register (WCR) and backed by four 6-bit nonvolatile Data Registers (DR0–DR3). Wiper position is updated via SPI commands including Write/Read WCR, XFR between DR and WCR, and real-time Increment/Decrement mode.

It supports standard SPI timing at up to 2 MHz, uses A0/A1 pins for slave addressing (up to 4 devices on bus), and features HOLD pin for pausing serial transfers without resetting state. Hardware write protection (WP) disables nonvolatile writes when pulled low, and power-up automatically loads DR0 into each WCR.

Key Specifications

Pinout & Package

Package: 24-lead SOIC (300 mil), Pb-free, RoHS-compliant (PKG Drawing M24.3).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5204BRUZ10 and MCP42050-I/P, the X9401WS24IZ-2.7T1 uniquely combines hardware write protection, low 150 Ω wiper resistance, and HOLD functionality in a single 2.7–5.5 V supply device-making it optimal for noise-sensitive, field-upgradable industrial analog systems requiring guaranteed configuration integrity.

Availability

X9401WS24IZ-2.7T1 is available at Aetrix Electronics and suitable for programmable power supplies, sensor calibration modules, audio level controls, and industrial DAC scaling applications requiring stable component supply and long-term configuration retention.

Supply support for X9401WS24IZ-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 Corporation is a leading provider of precision analog and power management solutions, now part of Renesas Electronics, with deep expertise in configurable mixed-signal ICs for industrial and infrastructure markets.

The X9401 product line was designed for digitally reconfigurable analog signal conditioning-targeting applications where mechanical potentiometers lack reliability, repeatability, or remote programmability.

FAQ

What is the minimum operating voltage for the X9401WS24IZ-2.7T1?

The X9401WS24IZ-2.7T1 operates from 2.7 V to 5.5 V. Its "-2.7" suffix explicitly denotes this extended low-voltage capability, enabling direct compatibility with 3.3 V systems without level-shifting. Below 2.7 V, SPI communication may become unreliable and wiper positioning may not be retained across power cycles. The X9401WS24IZ-2.7T1 maintains full functionality-including nonvolatile register writes and 64-tap resolution-at 2.7 V nominal supply.

Does the X9401WS24IZ-2.7T1 support true 4-wire potentiometer configurations?

No, the X9401WS24IZ-2.7T1 does not support true 4-wire (Kelvin) sensing. Each potentiometer has three dedicated terminals-VH, VL, and VW-and internally connects the resistor array between VH and VL, with switches routing one of 64 taps to VW. While VH/VL serve as force-sense points, there is no separate sense path for wiper voltage; measurement accuracy depends on 150 Ω typical wiper resistance and layout parasitics. For precision 4-wire applications, external op-amp buffering is required.

How does the HOLD pin function during an active SPI transaction on the X9401WS24IZ-2.7T1?

The HOLD pin on the X9401WS24IZ-2.7T1 pauses an ongoing SPI transaction without resetting internal state. To initiate hold, HOLD must be driven LOW while SCK is LOW; the device freezes the current instruction and data pointer. To resume, HOLD is returned HIGH (again while SCK is LOW), and the next SCK edge continues from the exact point of interruption. This enables multi-master arbitration or MCU interrupt servicing without losing command context-unlike CS deassertion, which aborts the sequence.

Can the X9401WS24IZ-2.7T1 be used as a standalone 16-byte EEPROM?

Yes-the X9401WS24IZ-2.7T1 provides 16 bytes of nonvolatile memory accessible via its four 6-bit Data Registers (DR0–DR3), with two bits unused per register. These registers support full read/write cycles independent of wiper position. However, write endurance is rated at 100,000 cycles per bit, and each write takes up to 10 ms. It is suitable for infrequently updated system parameters or calibration coefficients-but not for high-frequency logging. All 16 bytes retain data for 100 years at +85°C.

What happens to wiper positions after power cycling the X9401WS24IZ-2.7T1?

Upon power-up, the X9401WS24IZ-2.7T1 automatically loads the contents of Data Register 0 (DR0) into each channel's volatile Wiper Counter Register (WCR), restoring the last-saved wiper position. Since WCR itself is volatile, wiper state is lost during power-down unless explicitly stored to DR0 beforehand. To ensure repeatable startup behavior, firmware must execute "XFR DR0 to WCR" or write desired values to DR0 during initialization or before shutdown. DR0 retains its value for 100 years without power.