Renesas ISL22511WFB8Z

Overview

ISL22511WFB8Z from Renesas Electronics is a low-noise, low-power, 32-tap digitally controlled potentiometer (XDCP™) with push-button up/down control, AUTOSTORE, and shutdown mode. It features 10kΩ end-to-end resistance, ±3µA standby current, 32 wiper positions, and operates from 2.7V to 5.5V. It is used in LED brightness control circuits where mechanical potentiometer replacement and non-volatile wiper position retention are required.

For engineers reviewing the ISL22511WFB8Z datasheet, ISL22511WFB8Z pinout, ISL22511WFB8Z application, or ISL22511WFB8Z equivalent, key selection considerations include its UTQFN-10 package footprint, push-button interface without I²C/SPI, wiper auto-increment timing behavior, and EEPROM endurance of 1 million cycles at ≤+55°C.

Technical Context

The ISL22511WFB8Z implements a 31-element resistor array with a CMOS wiper switching network controlled by a 5-bit up/down counter. Its push-button logic includes hardware debounce (15–28ms), slow/fast scan modes triggered by button hold duration (>1s), and dual-input shutdown activation (PU & PD held low ≥2s).

It integrates non-volatile storage for wiper position via on-chip EEPROM with AUTOSTORE enabled by ASE pin state at power-up, or manual store via ASE pulse. Terminal voltage range is 0V to VCC, and wiper resistance is specified from 130Ω to 500Ω at VCC = 3.3V with IRW = VCC/RTOTAL.

Key Specifications

Pinout & Package

ISL22511WFB8Z is housed in a 10-lead Ultra Thin Quad Flat No-Lead (UTQFN) package measuring 2.1mm × 1.6mm × 0.45mm (max), RoHS-compliant and moisture-sensitive level MSL3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD5171BRMZ-10 and MCP4017T-103I/OT, the ISL22511WFB8Z uniquely combines push-button autonomy, factory-default max-scale power-up, and guaranteed 1M-cycle EEPROM retention - making it optimal for maintenance-free, user-adjustable analog trimming in space-constrained industrial designs.

Availability

ISL22511WFB8Z is available at Aetrix Electronics and suitable for LED brightness control, volume adjustment, contrast regulation, and programmable bias voltage generation requiring stable component supply and long-term obsolescence management.

Supply support for ISL22511WFB8Z 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 timing solutions.

The ISL22511WFB8Z belongs to Renesas' XDCP™ (eXternally Controlled Digital Potentiometer) family, designed specifically for replacing mechanical potentiometers in industrial, automotive, and consumer systems where robustness, non-volatility, and tactile control are essential.

FAQ

What is the default wiper position of the ISL22511WFB8Z at power-up?

The ISL22511WFB8Z is factory-programmed with the wiper set to the highest position (0x1Fh, tap 31) at power-up. This behavior is fixed and independent of ASE pin state or prior EEPROM contents. The device maintains this default unless AUTOSTORE is enabled and a valid stored value exists from a previous power cycle.

Does the ISL22511WFB8Z require an external microcontroller to operate?

No, the ISL22511WFB8Z operates autonomously using only two push-button switches connected to PU and PD inputs. It contains integrated debounce logic, a 5-bit up/down counter, EEPROM, and resistor array - eliminating the need for firmware, clock sources, or serial communication. The ISL22511WFB8Z is fully functional as a standalone analog trim component.

How does shutdown mode affect the electrical connections in the ISL22511WFB8Z?

In shutdown mode, the ISL22511WFB8Z disconnects the RH terminal from the resistor chain and forces the wiper to the lowest position (tap 0, closest to RL). This configuration isolates the top of the array and minimizes leakage current to ≤3µA. RH becomes electrically floating relative to the array, while RW and RL remain connected - preserving safe bias conditions in downstream circuitry.

Can the ISL22511WFB8Z be used in rheostat mode, and how is it configured?

Yes, the ISL22511WFB8Z supports rheostat mode by leaving either RH or RL unconnected and using RW with the remaining terminal. For example, connecting RW to RL and leaving RH open creates a variable resistance between RW and RL. The device maintains monotonicity and specifies RINL ≤±1.5MI and RDNL ≤±0.5MI in this configuration, ensuring predictable linear adjustment.

What is the meaning of "AUTOSTORE enabled if ASE is held LOW during power-up" for the ISL22511WFB8Z?

This means the ISL22511WFB8Z automatically writes the current wiper position to EEPROM upon power-down *only if* the ASE pin is externally held at logic LOW (e.g., tied to VSS) at the moment VCC rises above the power-on reset threshold. If ASE is HIGH at power-up, AUTOSTORE is disabled, and wiper position is retained only via manual store commands triggered by ASE pulses.