Renesas ISL23318UFRUZ-T7A

Overview

ISL23318UFRUZ-T7A from Renesas Electronics is a volatile, low-voltage, 128-tap digitally controlled potentiometer (DCP) with I²C interface, 10kΩ total resistance, ±0.15 LSB integral nonlinearity, and operation from 1.2V VLOGIC to 5.5V VCC. It functions as a precision voltage divider or rheostat in battery-powered sensor trimming and power supply margining circuits.

For engineers reviewing the ISL23318UFRUZ-T7A datasheet, ISL23318UFRUZ-T7A pinout, ISL23318UFRUZ-T7A application, or ISL23318UFRUZ-T7A equivalent, key selection criteria include its dual-supply independence (VLOGIC down to 1.2V), shutdown mode with internal RW–RL short, 70Ω typical wiper resistance at 3.3V, and guaranteed monotonicity across –40°C to +125°C.

Technical Context

The ISL23318UFRUZ-T7A implements a resistor ladder with CMOS make-before-break wiper switches controlled by a volatile 7-bit Wiper Register (WR), initialized to 64 (mid-scale) at power-on. Its I²C interface supports up to 4 devices per bus via A0/A1 address pins and requires no external level shifter for 1.2V–5.5V logic.

It operates in two primary modes: voltage divider (RH–RL–RW) with 0–VCC terminal voltage range and ratiometric temperature coefficient as low as 8 ppm/°C (10kΩ option), or rheostat (RW–RL or RW–RH) with ±0.15 MI differential nonlinearity and 300 ns large-signal wiper settling time.

Key Specifications

Pinout & Package

ISL23318UFRUZ-T7A is packaged in a 10-lead UTQFN (2.1mm × 1.6mm, 0.5mm pitch) with wettable flanks, RoHS-compliant NiPdAu (e4) termination.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5170BRMZ-10 and MCP45HV51-103E/MS, the ISL23318UFRUZ-T7A offers lower power (10µA vs 100µA), guaranteed mid-scale power-on reset, and superior tempco (8 ppm/°C vs 125 ppm/°C), making it optimal for precision, low-energy embedded calibration.

Availability

ISL23318UFRUZ-T7A is available at Aetrix Electronics and suitable for battery-powered instrumentation, sensor signal conditioning, and power supply margining requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for ISL23318UFRUZ-T7A 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 trusted embedded solutions, including high-performance analog, mixed-signal, and power management ICs for automotive, industrial, and IoT markets.

The ISL23318 series is part of Renesas' precision analog portfolio, designed specifically for low-power, high-accuracy digital trimming in space-constrained, thermally demanding applications such as portable medical devices and automotive subsystems.

FAQ

What is the default wiper position of the ISL23318UFRUZ-T7A at power-on?

The ISL23318UFRUZ-T7A initializes its volatile Wiper Register (WR) to 0x40 (64 decimal) at power-on, placing the wiper at mid-scale - exactly halfway between RL and RH terminals. This behavior is guaranteed across all operating conditions and ensures predictable startup in voltage divider configurations without requiring host initialization.

Does the ISL23318UFRUZ-T7A support true 1.2V I²C communication?

Yes, the ISL23318UFRUZ-T7A supports full I²C functionality with VLOGIC as low as 1.2V, including valid VIH/VIL thresholds, SDA/SCL timing compliance, and ACK generation. Its internal level shifter eliminates the need for external translators, enabling direct connection to 1.2V/1.8V microcontrollers while VCC operates at 3.3V or 5V.

How does shutdown mode affect the ISL23318UFRUZ-T7A's terminals?

In shutdown mode (SHDN bit = 0 in ACR), the ISL23318UFRUZ-T7A opens the RH–RL path and internally connects RW to RL through a ~2kΩ resistor. The wiper register retains its last value, and upon exit from shutdown, the wiper returns to that position after ≤1.5µs settling time - preserving calibration state without host intervention.

What is the maximum recommended wiper current for the ISL23318UFRUZ-T7A?

The absolute maximum wiper current for the ISL23318UFRUZ-T7A is ±6mA for short durations (≤10s), but the recommended operating limit is ±3mA. Exceeding ±3mA risks increased self-heating, resistance drift, and accelerated wear - especially critical in precision sensor bias networks where thermal EMF must be minimized.

Can the ISL23318UFRUZ-T7A be used in rheostat mode with only two terminals?

Yes, the ISL23318UFRUZ-T7A supports true two-terminal rheostat operation: connect either RW–RL (with RH floating) or RW–RH (with RL floating). In this mode, it delivers ±0.15 MI DNL and 1.2MHz bandwidth (10kΩ), enabling accurate programmable current limiting or gain control without third-terminal constraints.