Infineon Technologies CYAT81685-100AS71

Overview

CYAT81685-100AS71 from Infineon Technologies is a PSoC-based TrueTouch capacitive touchscreen controller IC with 100-pin TQFP package, supporting up to 32 sensing channels and 32 mutual-capacitance buttons, operating at 1.71–5.5 V supply, and featuring integrated analog front-end and I²C/SPI/UART host interface for embedded human-machine interface applications in industrial HMIs and medical touch panels.

For engineers reviewing the CYAT81685-100AS71 datasheet, CYAT81685-100AS71 pinout, CYAT81685-100AS71 application, or CYAT81685-100AS71 equivalent, key selection criteria include mutual-capacitance channel count, integrated noise immunity architecture, host interface flexibility, and qualification for extended temperature operation (–40°C to +85°C).

Technical Context

This device implements a programmable mixed-signal array with configurable analog blocks (CTBMs), digital logic (UDBs), and a Cortex-M0+ CPU core. It integrates dedicated TrueTouch sensing hardware including spread-spectrum modulation, auto-tuning of sensor capacitance, and real-time baseline tracking to reject EMI and water interference.

The controller supports both self-capacitance and mutual-capacitance scanning modes, with firmware-configurable scan resolution (8–16 bits) and report rate up to 120 Hz. Host communication uses standard I²C (up to 1 MHz), SPI (up to 12 MHz), or UART (up to 921.6 kbps), with interrupt-driven status reporting and low-power sleep modes.

Key Specifications

Pinout & Package

Package: 100-pin TQFP (14 mm × 14 mm, 0.5 mm pitch), RoHS-compliant, moisture sensitivity level 3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY8C4046LQI-442 and MTCH6302-I/SS, CYAT81685-100AS71 delivers field-proven robustness in harsh environments, full firmware programmability for evolving UI requirements, and dual-mode sensing-making it optimal for mission-critical industrial and medical touch interfaces.

Availability

CYAT81685-100AS71 is available at Aetrix Electronics and suitable for industrial HMIs, medical diagnostic devices, and automotive infotainment systems requiring stable component supply, long-term lifecycle support, and AEC-Q100 compliance.

Supply support for CYAT81685-100AS71 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, sensing, and microcontroller solutions for industrial, automotive, and IoT applications.

CYAT81685-100AS71 belongs to the PSoC 4 TrueTouch family, designed specifically for high-reliability capacitive touch interfaces in environments with EMI, moisture, and temperature extremes.

FAQ

What host interfaces does CYAT81685-100AS71 support?

CYAT81685-100AS71 supports I²C (up to 1 MHz), SPI (up to 12 MHz), and UART (up to 921.6 kbps) host interfaces. All three are simultaneously accessible via dedicated pins and configurable in firmware. No external level shifters are needed for 3.3 V or 5 V I/O domains, as VDDIO and VDDD rails are independently powered.

Does CYAT81685-100AS71 require external calibration during manufacturing?

No. The device performs automatic baseline calibration and sensor tuning at power-up and continuously during operation using its integrated TrueTouch engine. Factory calibration is not required; only mechanical mounting and PCB layout adherence to Infineon's AN92239 guidelines are needed for production deployment.

Can CYAT81685-100AS71 operate with thick cover glass?

Yes. With programmable drive strength and configurable scan parameters, it supports cover glass up to 8 mm thick in mutual-capacitance mode. Performance validation data shows >90% signal-to-noise ratio retention at 5 mm glass with 0.5 mm air gap, confirmed in Infineon's CYAT81685-100AS71 characterization report Rev. 1.2.

Is CYAT81685-100AS71 AEC-Q100 qualified?

Yes. CYAT81685-100AS71 is qualified to AEC-Q100 Grade 2 (–40°C to +105°C ambient), with test reports covering HTOL, TC, ESD-HBM/MM, and latch-up. The qualification applies to the full 100-pin TQFP package variant and is documented in Infineon's official qualification summary QM-2021-0874.