Renesas ISL90810WAU8Z

Overview

ISL90810WAU8Z from Intersil is a single-channel, digitally controlled potentiometer (XDCP™) with 256 taps, I²C interface, 10kΩ total resistance, ±0.75 LSB DNL in voltage divider mode, and operation over –40°C to +105°C. It functions as a precision programmable resistor or voltage divider in analog signal conditioning circuits.

For engineers reviewing the ISL90810WAU8Z datasheet, ISL90810WAU8Z pinout, ISL90810WAU8Z application, or ISL90810WAU8Z equivalent, key selection criteria include its automotive-grade temperature range, mid-scale power-on default, low 70Ω typical wiper resistance, 5µA max standby current, and compatibility with standard I²C bus timing at 400kHz.

Technical Context

The ISL90810WAU8Z implements a monolithic CMOS digital potentiometer using resistor ladders and CMOS switches, controlled exclusively via an I²C slave interface with fixed 0x50 (0101000b) 7-bit address. Its volatile 8-bit Wiper Register (WR) directly sets tap position (0–255), with hardware-initiated reset to 128 (mid-scale) on power-up.

It supports two operating configurations: three-terminal voltage divider (RH–RW–RL) and two-terminal rheostat (RW–RL or RW–RH), with ratiometric temperature coefficient of ±4 ppm/°C in divider mode and ±35 ppm/°C in rheostat mode. All DCP pins tolerate voltages from GND to VCC, and leakage remains below 1 µA across the full operating range.

Key Specifications

Pinout & Package

ISL90810WAU8Z is housed in an 8-lead MSOP (Mini Small Outline Plastic) package per JEDEC MO-187-AA, with 0.65mm pitch, 3.0mm × 3.0mm body, and exposed pad not present. Pin 1 is marked by a dot or beveled corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ISL90810WAU8Z, AD5170BRMZ-10 offers wider temperature coverage but looser linearity, while MCP4017T-103I/OT trades resolution and temp grade for lower unit cost - making ISL90810WAU8Z optimal for automotive-qualified, high-linearity analog trimming.

Availability

ISL90810WAU8Z is available at Aetrix Electronics and suitable for automotive lighting control, industrial sensor calibration, professional audio equipment, and telecom power supply trimming requiring stable component supply across extended temperature ranges.

Supply support for ISL90810WAU8Z 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 precision analog and power management ICs for industrial, automotive, and infrastructure markets.

The ISL90810 product line delivers digitally programmable analog components optimized for replacing mechanical potentiometers in harsh-environment applications requiring long-term reliability and repeatable calibration.

FAQ

What is the power-on behavior of the ISL90810WAU8Z?

At power-up, the ISL90810WAU8Z automatically resets its volatile Wiper Register to 0x80 (128 decimal), positioning the wiper at mid-scale regardless of prior state. This occurs after VCC exceeds the power-on recall threshold (1.8–2.6V) and completes within 3ms. The ISL90810WAU8Z does not retain settings across power cycles unless paired with external nonvolatile storage.

Does the ISL90810WAU8Z support write-protection or lock functionality?

No, the ISL90810WAU8Z does not include hardware or software write-protection. Its Wiper Register is always volatile and writable via I²C at any time. Protection must be implemented externally - for example, by disabling the I²C bus or gating SCL/SDA signals in system firmware. The ISL90810WAU8Z relies on standard I²C address matching (0x50) for basic access control only.

Can the ISL90810WAU8Z be used in rheostat mode with only two terminals?

Yes, the ISL90810WAU8Z supports true two-terminal rheostat operation by connecting either RH or RL to the same node as RW and leaving the unused terminal open. In this configuration, resistance between RW and RL (or RW and RH) varies from near-zero to 10kΩ. DNL remains ±0.75 LSB, and TCR is ±35 ppm/°C - confirmed in the datasheet's rheostat-mode specifications on page 4.

What is the maximum signal voltage that can be applied across RH and RL of the ISL90810WAU8Z?

The ISL90810WAU8Z allows voltage differentials up to VCC across RH and RL, provided neither pin exceeds the absolute maximum rating of –0.3V to VCC +0.3V relative to GND. For example, with VCC = 5.5V, RH may be at 5.5V and RL at 0V (5.5V differential), but RH must never exceed 5.8V or drop below –0.3V. Exceeding these limits risks latch-up or permanent damage.

Is the ISL90810WAU8Z pin-compatible with other members of the ISL90810 family?

Yes, all ISL90810 variants - including ISL90810WAU8Z, ISL90810UAU8Z, ISL90810WIU8Z, and ISL90810UIU8Z - share identical 8-lead MSOP packaging, pinout, and I²C interface. Differences are limited to total resistance (10kΩ vs 50kΩ) and temperature grade (–40°C to +105°C vs –40°C to +85°C), so PCB layout is fully reusable across the family.