Infineon Technologies CYAT81689-100AS71Z

Overview

CYAT81689-100AS71Z from Infineon Technologies is a capacitive touch controller IC designed for single-chip self-capacitive and mutual-capacitive sensing in touchscreen and touchpad applications. It supports up to 16 sense channels, operates at 3.3 V supply, integrates on-chip analog front-end and digital signal processor, and delivers <15 µs per sensor scan with built-in noise suppression for EMI-rich environments.

For engineers reviewing the CYAT81689-100AS71Z datasheet, CYAT81689-100AS71Z pinout, CYAT81689-100AS71Z application, or CYAT81689-100AS71Z equivalent, key selection criteria include channel count, integrated DSP capability, I²C/SPI interface support, operating voltage range, and ESD tolerance (±8 kV HBM) required for consumer and industrial human-interface designs.

Technical Context

This device implements a dedicated capacitive sensing architecture with configurable scan resolution (8–16 bits), real-time baseline tracking, and adaptive thresholding to maintain stable touch detection across temperature and humidity variations. Its embedded firmware handles raw capacitance-to-digital conversion, gesture recognition primitives (tap, swipe, hold), and host communication via I²C or SPI at up to 1 MHz.

The controller uses a sigma-delta ADC with programmable gain and integrates a 32-bit RISC core for local processing-eliminating need for external microcontroller intervention in basic touch event handling. All calibration and compensation routines execute autonomously during active operation without host CPU involvement.

Key Specifications

Pinout & Package

Package: 48-pin QFN (7 mm × 7 mm, 0.5 mm pitch), thermally enhanced with exposed thermal pad.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar capacitive touch controller applications.

Compared with AT42QT2120 and BU21022GWZ, CYAT81689-100AS71Z uniquely combines full on-chip gesture processing, dual-interface flexibility, and industrial-grade ESD tolerance-making it optimal for demanding embedded HMI where reliability and autonomous operation are mandatory.

Availability

CYAT81689-100AS71Z is available at Aetrix Electronics and suitable for smartphone touchscreen modules, industrial HMI panels, and medical tablet interfaces requiring stable component supply and long-term design-in support.

Supply support for CYAT81689-100AS71Z 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, automotive ICs, and human-interface solutions with global manufacturing and qualification infrastructure.

CYAT81689-100AS71Z belongs to Infineon's TrueTouch® family-designed specifically for high-reliability capacitive touch applications in harsh electromagnetic and environmental conditions.

FAQ

What is the maximum supported sense electrode size for CYAT81689-100AS71Z?

The device supports individual electrodes up to 100 pF total capacitance, including trace and overlay parasitics. Layout guidelines specify trace width ≥0.2 mm, spacing ≥0.25 mm, and guard ring implementation to maintain signal integrity beyond 50 pF nominal electrode values.

Does CYAT81689-100AS71Z require external firmware loading during startup?

No. The device contains factory-programmed boot ROM and non-volatile configuration memory. Default firmware and calibrated parameters are loaded automatically at power-on; user-defined configurations can be stored in on-chip EEPROM without external flash.

Can CYAT81689-100AS71Z operate with 1.8 V I/O signaling?

No. All digital I/O pins (I²C, SPI, INT, RST) are strictly 3.3 V tolerant and require 3.3 V logic levels. Interfacing with 1.8 V hosts necessitates level-shifting circuitry on all signal lines.

Is there hardware support for proximity wake-up without host intervention?

Yes. The device includes a dedicated low-power proximity mode that monitors selected channels at 10 Hz while consuming <15 µA. It asserts the INT pin autonomously upon threshold crossing-enabling wake-from-sleep without host polling.