Renesas ISL23318TFUZ-TK

Overview

ISL23318TFUZ-TK from Renesas Electronics is a volatile, low-voltage, I²C-compatible digitally controlled potentiometer (DCP) with 128 taps, 100kΩ total resistance, 10-lead MSOP package, and extended industrial temperature range (–40°C to +125°C). It functions as a programmable three-terminal potentiometer or two-terminal rheostat in precision analog trimming applications including sensor calibration and power supply margining.

For engineers reviewing the ISL23318TFUZ-TK datasheet, ISL23318TFUZ-TK pinout, ISL23318TFUZ-TK application, or ISL23318TFUZ-TK equivalent, key selection criteria include its dual-supply capability (VCC = 1.7–5.5V, VLOGIC = 1.2–5.5V), mid-scale power-on default (64 tap), shutdown mode with RW-to-RL short, and guaranteed monotonicity in both voltage divider and rheostat modes.

Technical Context

The ISL23318TFUZ-TK implements a resistor ladder with CMOS wiper switches controlled via an I²C interface, supporting direct read/write of a volatile 7-bit Wiper Register (WR). Its make-before-break switching ensures glitch-free wiper transitions, and internal level-shifting enables independent logic and analog supply rails.

It operates in two primary configurations: voltage divider mode (RH–RW–RL) with ±0.15 LSB INL/DNL and ratiometric temperature coefficient as low as 2.3 ppm/°C, and rheostat mode (RW–RL or RW–RH) with offset ≤1.0 MI and differential non-linearity ±0.15 MI - all verified across –40°C to +125°C.

Key Specifications

Pinout & Package

ISL23318TFUZ-TK is housed in a RoHS-compliant 10-lead MSOP package (3.0mm × 4.9mm, 0.5mm pitch), optimized for space-constrained PCB layouts while maintaining thermal performance (θ_JA = 170°C/W).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5171BRMZ-100 and MCP45HV51-103E/MS, the ISL23318TFUZ-TK uniquely combines volatile mid-scale reset, dual-supply flexibility (1.2V logic), and guaranteed monotonicity at 128 taps - making it optimal for battery-powered calibration and closed-loop thermal compensation where startup predictability and low-noise analog integrity are essential.

Availability

ISL23318TFUZ-TK is available at Aetrix Electronics and suitable for gain adjustment in portable instruments, trimming sensor circuits, and power supply margining requiring stable component supply across automotive, industrial, and medical electronics programs.

Supply support for ISL23318TFUZ-TK 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 high-performance analog, mixed-signal, and embedded processing solutions for automotive, industrial, and IoT markets.

The ISL23318 series was designed specifically for precision analog trimming in resource-constrained, battery-operated, and thermally demanding systems - emphasizing low-voltage operation, I²C simplicity, and guaranteed monotonic performance across extended temperature ranges.

FAQ

What is the default wiper position of the ISL23318TFUZ-TK at power-on?

The ISL23318TFUZ-TK powers up with its volatile Wiper Register (WR) preset to 64 (hex 40), placing the wiper at mid-scale - i.e., approximately 50kΩ between RH and RW, and 50kΩ between RW and RL in a 100kΩ device. This deterministic startup behavior ensures repeatable initial conditions in calibration and biasing circuits without requiring host initialization.

Can the ISL23318TFUZ-TK operate with different voltages on VCC and VLOGIC?

Yes - the ISL23318TFUZ-TK supports independent supplies: VCC from 1.7V to 5.5V for the analog resistor array, and VLOGIC from 1.2V to 5.5V for the I²C interface. This allows direct connection to 1.2V microcontroller I/Os without level shifters, while powering the DCP from a higher-voltage rail such as 3.3V or 5V - a key advantage in mixed-voltage embedded systems.

Does the ISL23318TFUZ-TK support shutdown mode, and what happens to the wiper?

Yes - setting bit 6 (SHDN) in the Access Control Register (ACR) places the ISL23318TFUZ-TK into shutdown mode, internally shorting RW to RL through ~2kΩ while opening the RH–RL path. The WR value is retained, and upon exit, the wiper returns to its pre-shutdown position within 1.5µs. This mode draws <2.8µA total supply current, ideal for battery conservation.

What is the maximum I²C clock frequency supported by the ISL23318TFUZ-TK?

The ISL23318TFUZ-TK supports standard-mode I²C up to 400kHz, with timing parameters fully characterized across its operating range (VLOGIC = 1.2V–5.5V, TA = –40°C to +125°C). Setup/hold times (e.g., tSU:STA = 600ns, tHD:STA = 600ns) and rise/fall times (tR/tF ≤ 250ns) comply with I²C specification requirements, ensuring robust communication even in noisy industrial environments.

How does the ISL23318TFUZ-TK ensure monotonicity in rheostat mode?

The ISL23318TFUZ-TK guarantees monotonicity in rheostat mode (RW–RL or RW–RH) with differential non-linearity (RDNL) of ±0.15 MI and integral non-linearity (RINL) of ±0.15 MI over temperature - verified for the 100kΩ variant at VCC = 2.7V–5.5V. This ensures that resistance between terminals changes predictably and strictly increases/decreases with each WR increment, preventing output glitches in closed-loop bias control.