Renesas ISL90810WIU8Z

Overview

ISL90810WIU8Z from Intersil is a single-channel, digitally controlled potentiometer (XDCP™) with 256 taps, I²C interface, 10kΩ total resistance, 70Ω typical wiper resistance at 3.3V, and 8-lead MSOP package. It functions as a precision voltage divider or rheostat in analog signal conditioning circuits for industrial sensor calibration and power supply feedback loops.

For engineers reviewing the ISL90810WIU8Z datasheet, ISL90810WIU8Z pinout, ISL90810WIU8Z application, or ISL90810WIU8Z equivalent, key selection considerations include its ±0.5 LSB DNL (U-version), -40°C to +85°C operating range, volatile wiper register with power-on mid-scale (128) reset, low 5µA max standby current, and compatibility with standard 400kHz I²C bus timing.

Technical Context

The ISL90810WIU8Z implements a monolithic CMOS resistor ladder with CMOS switch matrix controlled by an 8-bit volatile Wiper Register (WR), directly accessible via I²C address 0x00 after identification byte 0x50 (R/W bit). Its architecture supports both voltage divider mode (RH–RL–RW) and rheostat mode (RW–RL or RW–RH), with monotonic tap transitions and guaranteed operation across 2.7V–5.5V supply.

It features ratiometric temperature coefficient of ±4 ppm/°C in voltage divider mode and ±35 ppm/°C in rheostat mode, with leakage <1 µA on DCP pins and 1 µs wiper response time after I²C command completion. The device enters standby state automatically after STOP condition, drawing ≤5 µA at 5.5V over full temperature range.

Key Specifications

Pinout & Package

Package: 8-lead MSOP (Pb-free, RoHS compliant), 3.0mm × 3.0mm body, 0.65mm pitch, M8.118 outline drawing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ISL90810WIU8Z, ISL90810UAU8Z-TK offers wider temperature range and higher resistance but lacks the exact 10kΩ/85°C match, while AD5170BRMZ-10 adds EEPROM retention at the cost of pinout incompatibility and different layout requirements.

Availability

ISL90810WIU8Z is available at Aetrix Electronics and suitable for industrial sensor calibration, programmable power supply feedback, and LCD panel brightness control requiring stable component supply and long-term design continuity.

Supply support for ISL90810WIU8Z 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, infrastructure, and high-end consumer markets.

The ISL90810 product line delivers digitally programmable resistance solutions optimized for low-noise, low-power, and high-linearity analog trimming in space-constrained embedded systems.

FAQ

What is the power-on behavior of the ISL90810WIU8Z wiper position?

The ISL90810WIU8Z wiper always initializes to mid-scale (128 tap position, WR = 0x80) at power-on, regardless of prior I²C writes. This deterministic startup ensures repeatable analog output without host firmware intervention. The ISL90810WIU8Z achieves this via internal POR circuitry that loads 0x80 into the volatile Wiper Register before the I²C interface becomes active.

Does the ISL90810WIU8Z support nonvolatile wiper storage?

No, the ISL90810WIU8Z uses a volatile Wiper Register only - wiper position is lost upon power removal. It does not include EEPROM or flash memory. To retain settings, the host microcontroller must reprogram the ISL90810WIU8Z's WR after each power cycle. This distinguishes the ISL90810WIU8Z from nonvolatile alternatives like the AD5170 series.

What is the maximum allowable wiper current for the ISL90810WIU8Z?

The ISL90810WIU8Z specifies ±3.0mA maximum wiper current (IW) under recommended operating conditions. Exceeding this may cause measurement inaccuracy or long-term reliability degradation. This limit applies whether used in voltage divider or rheostat mode, and is defined in the Absolute Maximum Ratings table of the ISL90810WIU8Z datasheet.

Can the ISL90810WIU8Z operate from a 2.5V supply?

No, the ISL90810WIU8Z has a minimum supply voltage of 2.7V per its Recommended Operating Conditions. Operation at 2.5V falls outside specification and may result in I²C communication failure, incorrect wiper positioning, or increased DNL/INL errors. The ISL90810WIU8Z requires VCC ≥ 2.7V to guarantee proper CMOS switch threshold margins and internal logic functionality.

How does the ISL90810WIU8Z handle I²C bus arbitration and clock stretching?

The ISL90810WIU8Z operates strictly as an I²C slave with no clock stretching capability - it completes all internal operations within the timing budget of a standard 400kHz I²C cycle. It does not drive SCL low to hold the bus; instead, it relies on fast 1µs wiper response and immediate ACK/NACK signaling. The ISL90810WIU8Z expects clean START/STOP conditions and will ignore commands if arbitration is lost on the bus.