Renesas X9408WV24Z

Overview

X9408WV24Z from Intersil (now Renesas) is a quad-channel digitally controlled potentiometer (XDCP™) IC implementing four independent 64-tap resistor arrays with volatile wiper counter registers and nonvolatile data registers, operating from 2.7V to 5.5V supply, supporting 2-wire I²C-compatible interface, and packaged in Pb-free 24-lead TSSOP for precision analog trimming in mixed-signal systems.

For engineers reviewing the X9408WV24Z datasheet, X9408WV24Z pinout, X9408WV24Z application, or X9408WV24Z equivalent, this page delivers verified specifications, validated pin functions, confirmed analog performance metrics (e.g., ±1% absolute linearity, 40Ω typical wiper resistance at 5V), and real-world use cases in programmable gain control, sensor calibration, and DC bias adjustment - all grounded in FN8191 Rev.4.00.

Technical Context

The X9408WV24Z integrates four monolithic CMOS resistor arrays (63 segments each), each with a 6-bit volatile Wiper Counter Register (WCR) and four 6-bit nonvolatile Data Registers (DR0–DR3). Wiper position is controlled via 2-wire serial commands including Read/Write WCR, Read/Write DR, and Increment/Decrement modes with sub-millisecond response (tWRL = 10µs).

It supports dual-supply analog operation (V+ = +2.7V to +5.5V, V− = −2.7V to −5.5V), enabling true bipolar signal conditioning. Hardware write protection (WP pin) disables nonvolatile register writes, and power-up automatically loads DR0 into each WCR - ensuring deterministic startup behavior without host initialization.

Key Specifications

Pinout & Package

Package: 24-lead Pb-free TSSOP (4.4mm width), RoHS compliant, MSL3 per JEDEC J-STD-020.

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/ST, the X9408WV24Z uniquely supports true bipolar analog operation via dedicated V+/V− rails and includes hardware write protection - making it the only option among the three suitable for precision AC-coupled signal conditioning with guaranteed calibration persistence.

Availability

X9408WV24Z is available at Aetrix Electronics and suitable for programmable gain amplifiers, sensor calibration modules, RF front-end biasing circuits, and audio level controllers requiring stable component supply, long-term calibration retention, and Pb-free compliance.

Supply support for X9408WV24Z 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 power management ICs for industrial, communications, and computing markets.

The X9408 product line was designed for precision analog trimming in mixed-signal systems requiring nonvolatile calibration storage, low-power operation, and robust I²C-based reconfiguration - targeting instrumentation, test equipment, and telecom infrastructure.

FAQ

What is the maximum clock frequency supported by the X9408WV24Z 2-wire interface?

The X9408WV24Z supports a maximum SCL clock frequency of 400kHz, as specified in the AC timing table of FN8191 Rev.4.00. This allows reliable communication with standard I²C masters while maintaining noise immunity and timing margins. The device does not support fast-mode plus (1MHz) or high-speed mode, and exceeding 400kHz may result in command failures or incomplete wiper updates. All timing parameters - including tSU:DAT (100ns setup) and tHD:DAT (30ns hold) - are validated at this rate.

Does the X9408WV24Z require external pull-up resistors on SCL and SDA lines?

Yes, the X9408WV24Z requires external pull-up resistors on both SCL and SDA lines because its SDA pin is open-drain and SCL is a CMOS input with no internal pull-up. The datasheet recommends calculating values based on bus capacitance and desired rise time; for typical 100pF bus loads, 2.2kΩ to 4.7kΩ resistors to VCC are appropriate. Failure to install pull-ups will prevent I²C communication entirely, as neither line can drive high without them.

How does the WP pin affect nonvolatile writes to the X9408WV24Z Data Registers?

When the WP pin is driven LOW, the X9408WV24Z blocks all nonvolatile write operations to its four Data Registers (DR0–DR3), including Write Data Register and XFR WCR-to-DR commands. Volatile operations - such as Read/Write Wiper Counter Register and Increment/Decrement - remain fully functional. This hardware lock prevents accidental overwriting of factory-calibrated values during system operation or firmware updates, and is active regardless of I²C command content.

Can the X9408WV24Z operate with only a single positive supply, or is the V− pin mandatory?

The V− pin is mandatory for correct operation of the X9408WV24Z analog section. While VCC powers the digital interface, the resistor arrays require both V+ and V− to establish the full analog voltage range. If V− is left unconnected or tied to VSS, the potentiometers will not function - wiper outputs become undefined and terminal voltages violate absolute maximum ratings. For unipolar-only applications, V− must still be connected (e.g., to VSS), but V+ must be ≥ VCC to satisfy (V+) − (V−) ≤ 12V and avoid latch-up.

What happens to the wiper position of the X9408WV24Z after power cycling?

Upon power-up, the X9408WV24Z automatically loads the contents of Data Register 0 (DR0) into each potentiometer's volatile Wiper Counter Register (WCR), restoring the last-saved wiper position. This occurs after VCC, V+, and V− reach stable levels (tPUR = 1ms min). If DR0 was never written, default value 0x00 applies - placing all wipers at the VL/RL terminal. No host intervention is required, enabling zero-touch startup in calibration-critical systems.