Renesas ISL22511UFB8Z-TK

Overview

ISL22511UFB8Z-TK from Renesas Electronics is a solid-state, non-volatile, 32-tap digitally controlled potentiometer (XDCP™) with push-button up/down control, shutdown mode, and AUTOSTORE functionality. It features 10kΩ end-to-end resistance, ±3.0mA wiper current capability, 3µA max standby current, and operates from 2.7V to 5.5V. It is used in LED brightness control circuits where precise, low-noise, zero-maintenance analog adjustment is required.

For engineers reviewing the ISL22511UFB8Z-TK datasheet, ISL22511UFB8Z-TK pinout, ISL22511UFB8Z-TK application, or ISL22511UFB8Z-TK equivalent, key selection considerations include its UTQFN-10 (2.1mm × 1.6mm) package, push-button interface without I²C/SPI, 1000000-cycle EEPROM endurance, and voltage-divider/rheostat configuration flexibility.

Technical Context

The ISL22511UFB8Z-TK implements a 31-element resistor ladder with a 5-bit up/down counter and debounced PU/PD inputs to select one of 32 wiper positions. Its internal control logic supports both single-step and auto-increment/decrement modes triggered by button press duration, with fast-scan activation after 1s.

Shutdown mode is entered when PU and PD are held low for ≥2s, disconnecting RH and moving wiper to RL; AUTOSTORE is enabled by holding ASE low at power-up, while manual store occurs on ASE low pulse >15ms. The device retains wiper position in non-volatile memory with 50-year data retention at ≤+55°C.

Key Specifications

Pinout & Package

ISL22511UFB8Z-TK uses a 10-lead UTQFN package (2.1mm × 1.6mm, 0.45mm max height), RoHS-compliant, with wettable flanks and no internal leadframe pullback per L10.2.1x1.6A drawing.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5171BRMZ-10 and MCP45HV51-103E/MC, the ISL22511UFB8Z-TK offers the smallest footprint (UTQFN-10), lowest standby current (3µA), and fastest human-interface response via native push-button logic-making it optimal for cost-sensitive, space-constrained, battery-aware analog adjustment tasks without MCU involvement.

Availability

ISL22511UFB8Z-TK is available at Aetrix Electronics and suitable for LED brightness control, contrast adjustment, volume regulation, and programmable bias voltage generation requiring stable component supply across automotive, industrial, and consumer electronics programs.

Supply support for ISL22511UFB8Z-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 Corporation is a global semiconductor leader delivering trusted embedded design innovation, with expertise in microcontrollers, analog, power, and connectivity solutions.

The ISL22511UFB8Z-TK belongs to Renesas' XDCP™ (eXternally Controlled Digital Potentiometer) family, designed specifically for replacing mechanical potentiometers in analog front-ends where reliability, size, and hands-free digital control are critical.

FAQ

What is the default wiper position of the ISL22511UFB8Z-TK at power-up?

The ISL22511UFB8Z-TK is factory-programmed with the wiper set to the highest position (0x1F hex, tap 31). This ensures maximum RH-to-RW resistance on initial power application, which is essential for fail-safe behavior in bias-critical circuits like amplifier gain control or LCD contrast initialization.

Does the ISL22511UFB8Z-TK require an external microcontroller to operate?

No, the ISL22511UFB8Z-TK operates autonomously using only two momentary push-button switches connected to PU and PD pins. Its integrated debounce logic, up/down counter, and EEPROM eliminate the need for firmware or serial communication-enabling true "plug-and-adjust" analog tuning in standalone systems.

How does shutdown mode affect the electrical connections in the ISL22511UFB8Z-TK?

In shutdown mode, the ISL22511UFB8Z-TK disconnects the RH terminal from the resistor array and moves the wiper to the RL terminal (tap 0), effectively shorting RW to RL. This reduces system leakage and isolates the RH node, making it ideal for power-gated display backlight or sensor bias circuits.

Can the ISL22511UFB8Z-TK be used in rheostat configuration, and how is it wired?

Yes, the ISL22511UFB8Z-TK supports rheostat mode: connect either RH or RL to the wiper (RW), leaving the other fixed terminal open. For example, tie RW to RL and use RH–RW as a two-terminal variable resistor. This configuration achieves ±3.0mA wiper current handling with monotonic 32-step resistance control.

What is the maximum allowable voltage applied to the RH and RL terminals of the ISL22511UFB8Z-TK?

The RH and RL terminals of the ISL22511UFB8Z-TK must remain within 0V to VCC. Applying voltage outside this range-even briefly-violates absolute maximum ratings and may cause latch-up or permanent damage. VCC must always be ≥ VRH and VRL to ensure safe operation per Renesas' power sequencing guidelines.