Renesas X9251US24IZ

Overview

X9251US24IZ from Renesas Electronics is a quad digitally controlled potentiometer (XDCP™) IC integrating four independent 256-tap, 50kΩ end-to-end resistance DCPs on a single monolithic CMOS die. It operates from 2.7V to 5.5V, features SPI serial interface, nonvolatile data registers with 100-year retention, and supports industrial temperature range (–40°C to +85°C). It serves as programmable voltage divider or variable resistor in precision analog trimming circuits.

For engineers reviewing the X9251US24IZ datasheet, X9251US24IZ pinout, X9251US24IZ application, or X9251US24IZ equivalent, this page delivers verified technical context, real-world use cases, validated alternatives, and supply-ready procurement details - all grounded in the FN8166 Rev 7.00 datasheet and Renesas official specifications.

Technical Context

The X9251US24IZ implements four independent digital potentiometers using resistor arrays and CMOS switches, each with an 8-bit volatile Wiper Counter Register (WCR) and four 8-bit nonvolatile Data Registers (DR00–DR33). Wiper position is updated via SPI commands including Write/Read WCR, Write/Read DR, and XFR between DR and WCR.

It uses standard SPI-3-wire protocol (CS, SCK, SI/SO) with device addressing via A0/A1 pins, hardware write protection (WP), and HOLD for serial bus pause. Power-up loads DR#0 values into corresponding WCRs; standby current is <5µA, and wiper resistance is 100Ω typical at VCC = 5V.

Key Specifications

Pinout & Package

Package: 24-lead TSSOP (4.4mm width), RoHS-compliant, Pb-free, moisture sensitivity level per MSL3 (per Renesas TB363).

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/SL, the X9251US24IZ offers superior channel density, finer resolution, longer data retention, and dedicated hardware write protection - making it optimal for industrial calibration-critical systems requiring four independent, field-updatable trim functions.

Availability

X9251US24IZ is available at Aetrix Electronics and suitable for industrial sensor conditioning, RF power amplifier biasing, precision instrumentation offset trimming, and audio signal path gain control requiring stable component supply across extended temperature and lifecycle requirements.

Supply support for X9251US24IZ 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

Renesas Electronics is a global semiconductor leader delivering microcontrollers, analog power, and mixed-signal solutions for automotive, industrial, and IoT applications.

The X9251US24IZ belongs to Renesas' XDCP™ family of digitally controlled potentiometers, designed specifically for replacing mechanical trimpots in automated calibration, closed-loop feedback, and programmable analog signal conditioning systems.

FAQ

What is the operating voltage range for the X9251US24IZ?

The X9251US24IZ operates from 2.7V to 5.5V, supporting both 3.3V and 5V logic systems. Its VCC pin must always be more positive than or equal to voltages applied to RH, RL, and RW terminals. This single-supply capability simplifies power design in mixed-voltage embedded systems while maintaining full 256-tap resolution and nonvolatile functionality across the range.

How many nonvolatile data registers does the X9251US24IZ provide per potentiometer?

The X9251US24IZ provides four 8-bit nonvolatile Data Registers (DR00–DR03, DR10–DR13, etc.) for each of its four potentiometers. These registers store wiper positions or system parameters with 100-year data retention and 100,000 write endurance. At power-up, DR#0 values are automatically loaded into their respective Wiper Counter Registers, ensuring repeatable startup behavior without host intervention.

Can the X9251US24IZ be used as a two-terminal variable resistor?

Yes, the X9251US24IZ can be configured as a two-terminal variable resistor by connecting either RH or RL to the same node (e.g., ground or VCC) and using RW as the adjustable terminal. This configuration is commonly used in amplifier gain-setting networks and current-limiting circuits. The 50kΩ end-to-end resistance and 100Ω typical wiper resistance directly determine the effective resistance range and loading effects in such applications.

What is the purpose of the HOLD pin on the X9251US24IZ?

The HOLD pin on the X9251US24IZ pauses ongoing SPI communication without resetting the internal command state. When asserted LOW while SCK is LOW, it suspends data transfer mid-sequence; bringing HOLD HIGH resumes operation from the exact point of interruption. This enables deterministic bus arbitration in multi-master systems and prevents SPI corruption during host interrupt service routines - a feature not found in basic digital potentiometers.

Does the X9251US24IZ support daisy-chained SPI connections?

The X9251US24IZ does not natively support daisy-chaining due to its dedicated SO output and lack of cascaded shift-register architecture. However, its SO and SI pins are three-state capable and can be wired in parallel (shared bus) with proper CS decoding. For multi-device configurations, Renesas recommends using A0/A1 address pins to assign unique slave addresses - enabling up to four X9251US24IZ devices on one SPI bus with individual CS lines.