Renesas ISL23318WFRUZ-T7A

Overview

ISL23318WFRUZ-T7A from Renesas Electronics is a volatile, low-voltage, I²C-compatible digitally controlled potentiometer (DCP) with 128 taps, 10kΩ total resistance, and UTQFN-10 package. It operates from 1.7V to 5.5V analog supply (VCC) and 1.2V to 5.5V logic supply (VLOGIC), features 70Ω typical wiper resistance at 3.3V, and powers on to mid-scale (64). It is used for precision gain adjustment in battery-powered instrumentation.

For engineers reviewing the ISL23318WFRUZ-T7A datasheet, ISL23318WFRUZ-T7A pinout, ISL23318WFRUZ-T7A application, or ISL23318WFRUZ-T7A equivalent, key selection considerations include its dual-supply I²C interface (VLOGIC independent of VCC), shutdown mode behavior (RW shorted to RL via ~2kΩ), extended temperature range (–40°C to +125°C), and verified monotonicity in both voltage divider and rheostat modes.

Technical Context

The ISL23318WFRUZ-T7A implements a resistor ladder with CMOS switches and a volatile 7-bit Wiper Register (WR), enabling precise digital control of wiper position via I²C. Its "make-before-break" switching ensures glitch-free transitions between taps.

It supports two operating modes: voltage divider (RH–RL–RW) and rheostat (RW–RL or RW–RH), with guaranteed monotonicity (±0.15 LSB INL/DNL for 10kΩ option), ratiometric temperature coefficient of 8 ppm/°C (typ), and –65 dB digital feed-through suppression. Shutdown mode forces RH–RL open-circuit while internally connecting RW to RL.

Key Specifications

Pinout & Package

ISL23318WFRUZ-T7A is housed in a Pb-free, RoHS-compliant 10-lead UTQFN package (2.1mm × 1.6mm, 0.5mm pitch, L10.2.1x1.6A drawing), optimized for space-constrained PCB layouts and high thermal efficiency (θJA = 145°C/W).

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 ISL23318WFRUZ-T7A uniquely combines ultra-low-voltage I²C compatibility (1.2V VLOGIC), integrated shutdown with RW-to-RL shorting, and guaranteed monotonicity in both modes - making it optimal for compact, low-power, thermally demanding embedded systems.

Availability

ISL23318WFRUZ-T7A is available at Aetrix Electronics and suitable for gain adjustment in portable instruments, trimming sensor circuits, power supply margining, RF power amplifier bias compensation, and industrial temperature sensing requiring stable component supply and long-term parametric consistency.

Supply support for ISL23318WFRUZ-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 for automotive, industrial, infrastructure, and IoT applications, with deep expertise in precision analog and mixed-signal design.

The ISL23318 series belongs to Renesas' XDCP™ (eXtreme Digital Controlled Potentiometer) product line, engineered specifically for high-accuracy, low-power, and thermally robust digital trimming in battery-operated and mission-critical systems.

FAQ

What is the default wiper position after power-on for the ISL23318WFRUZ-T7A?

The ISL23318WFRUZ-T7A powers on with its volatile Wiper Register (WR) preset to 40h (64 decimal), placing the wiper at mid-scale - i.e., approximately 5kΩ between RL and RW, and 5kΩ between RW and RH for the 10kΩ device. This behavior is guaranteed across the full –40°C to +125°C temperature range and ensures a known, safe startup state for gain-critical circuits.

Does the ISL23318WFRUZ-T7A support true 1.2V I²C bus operation?

Yes - the ISL23318WFRUZ-T7A features a dedicated VLOGIC pin that accepts 1.2V to 5.5V, enabling direct connection to 1.2V, 1.8V, or 3.3V I²C masters without external level shifters. Its input thresholds scale with VLOGIC (VIH = 0.7×VLOGIC, VIL = 0.3×VLOGIC), and it draws only 5µA typical ILOGIC current at 1.2V/1.7V, making it ideal for ultra-low-power microcontroller interfaces.

How does shutdown mode affect the terminals of the ISL23318WFRUZ-T7A?

In shutdown mode (activated by setting SHDN bit in ACR register), the ISL23318WFRUZ-T7A forces RH–RL into an open circuit while internally connecting RW to RL through a ~2kΩ resistor. This configuration prevents floating outputs and provides a defined low-impedance path during system sleep - unlike simple high-Z states, it avoids unintended biasing of downstream circuitry.

Is the ISL23318WFRUZ-T7A monotonic in rheostat mode?

Yes - the ISL23318WFRUZ-T7A guarantees monotonicity in rheostat mode (RW–RL or RW–RH) with ±0.15 MI differential non-linearity (RDNL) and ±0.15 MI integral non-linearity (RINL) for the 10kΩ variant across VCC = 2.7V–5.5V. This is validated per datasheet Figure 5 and Figure 6, ensuring predictable, stepwise resistance changes critical for stable closed-loop control.

What package type and footprint does the ISL23318WFRUZ-T7A use?

The ISL23318WFRUZ-T7A uses a 10-lead UTQFN package measuring 2.1mm × 1.6mm with 0.5mm pitch (PKG DWG L10.2.1x1.6A). It features an exposed thermal pad for enhanced heat dissipation and is RoHS-compliant with NiPdAu (e4) termination - compatible with standard reflow profiles including Pb-free peak temperatures per J-STD-020.