Renesas ISL23415TFRUZ-T7A

Overview

ISL23415TFRUZ-T7A from Renesas Electronics is a volatile, low-voltage, SPI-interface digitally controlled potentiometer (XDCP™) with 256 taps, 100kΩ end-to-end resistance, and operation from 1.7V to 5.5V VCC and 1.2V to 5.5V VLOGIC. It features 70Ω typical wiper resistance at 3.3V, shutdown mode with <2.8µA max current, and operates across –40°C to +125°C for precision biasing in battery-powered RF and medical systems.

For engineers reviewing the ISL23415TFRUZ-T7A datasheet, ISL23415TFRUZ-T7A pinout, ISL23415TFRUZ-T7A application, or ISL23415TFRUZ-T7A equivalent, this device supports daisy-chained SPI configuration, mid-scale power-on default (128), and independent logic/analog supply rails - critical for low-power embedded calibration and analog signal trimming.

Technical Context

The ISL23415TFRUZ-T7A implements a monolithic CMOS resistor ladder with CMOS wiper switches, controlled via SPI Mode 0 (rising-edge clock, falling-edge data output). Its volatile Wiper Register (WR) directly sets tap position (0–255), with power-on reset to 128 (mid-scale) and no nonvolatile storage.

It supports dual-supply operation: VCC powers the analog DCP core (1.7V–5.5V), while VLOGIC powers the SPI interface (1.2V–5.5V), enabling direct connection to 1.2V microcontrollers without level shifters. Shutdown mode forces RH–RL open-circuit and shorts RW to RL via internal 2kΩ path.

Key Specifications

Pinout & Package

ISL23415TFRUZ-T7A is packaged in a 10-lead µTQFN (2.1mm × 1.6mm, 0.5mm pitch), RoHS-compliant with NiPdAu (e4) termination. Thermal resistance θJA = 145°C/W enables high-density placement without forced airflow.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5175BRMZ-100 and MCP45HV51-103E/MS, the ISL23415TFRUZ-T7A uniquely supports 1.2V logic-level SPI communication and independent analog/digital supplies - essential for modern ultra-low-power embedded systems where supply domain isolation and battery efficiency are design priorities.

Availability

ISL23415TFRUZ-T7A is available at Aetrix Electronics and suitable for power supply margining, RF amplifier bias compensation, LCD bias adjustment, and portable medical calibration requiring stable component supply across extended temperature and low-voltage operation.

Supply support for ISL23415TFRUZ-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 markets, with deep expertise in analog, power, and mixed-signal ICs.

The ISL23415 product line delivers digitally programmable analog trimming for precision, low-power, and thermally robust applications - designed specifically for battery-operated instrumentation, RF front-ends, and industrial calibration where supply flexibility and reliability are critical.

FAQ

What is the default wiper position of the ISL23415TFRUZ-T7A at power-up?

The ISL23415TFRUZ-T7A initializes its volatile Wiper Register (WR) to 128 (0x80 hex) at power-up, placing the wiper at mid-scale - ensuring safe, predictable startup in voltage divider or bias networks without transient overshoot. This behavior is guaranteed across the full –40°C to +125°C temperature range and all valid VCC/VLOGIC combinations.

Does the ISL23415TFRUZ-T7A support daisy-chaining with other ISL23415 devices?

Yes, the ISL23415TFRUZ-T7A supports SPI daisy-chaining: connect SDO of one device to SDI of the next, with shared SCK and CS lines. The host sends instructions in reverse order (last device first), enabling simultaneous wiper updates across multiple ISL23415TFRUZ-T7A units using a single SPI port - ideal for multi-channel calibration systems.

What is the maximum SPI clock frequency supported by the ISL23415TFRUZ-T7A?

The ISL23415TFRUZ-T7A supports up to 5MHz SCK frequency when VLOGIC ≥ 1.7V; at 1.2V–1.6V VLOGIC, the maximum is 1MHz. Timing parameters (tCYC = 200ns, tWH/tWL = 100ns) are fully specified in the datasheet to ensure reliable register access and wiper settling within 3.5µs for the 100kΩ variant.

How does the shutdown mode affect the DCP terminals of the ISL23415TFRUZ-T7A?

In shutdown mode (SHDN bit = 0 in ACR), the ISL23415TFRUZ-T7A opens the RH–RL path and internally shorts RW to RL via a 2kΩ resistor. This isolates the analog signal path while preserving the last wiper register value - allowing immediate restoration upon exit, with tShdnRec = 1.5µs. Terminal voltage must remain within 0V to VCC during transition.

Can the ISL23415TFRUZ-T7A be used as a two-terminal variable resistor?

Yes, the ISL23415TFRUZ-T7A can operate as a rheostat by connecting either RH or RL to the same node (e.g., GND or VCC) and using RW and the unconnected terminal. In this mode, resistance between RW and RL varies from ~0Ω to 100kΩ with monotonicity guaranteed (±0.3 MI DNL for T option), supporting precision current-source or gain-control applications.