Infineon Technologies CY8C20667S-24LQXI

Overview

CY8C20667S-24LQXI from Cypress Semiconductor is a 1.8 V CapSense® controller with SmartSense™ auto-tuning, integrating an M8C 8-bit Harvard-architecture CPU (24 MHz max), 31 capacitive sensing inputs, 6 slider channels, and proximity sensing capability. It delivers 0.1 pF sensitivity, 28 µA/sensor average active current (125 ms scan interval), and operates from –40 °C to +85 °C in a 48-pin QFN package.

For engineers reviewing the CY8C20667S-24LQXI datasheet, CY8C20667S-24LQXI pinout, CY8C20667S-24LQXI application, or CY8C20667S-24LQXI equivalent, key selection criteria include capacitive sensing channel count, SmartSense_EMC_PLUS runtime auto-tuning behavior, driven-shield GPIO support for water tolerance, I²C slave timing modes (50/100/400 kHz), and flash/SRAM configuration (32 KB/2 KB).

Technical Context

The device implements a dedicated CapSense PSoC block with CSD PLUS™ sigma-delta modulation, enabling hardware-accelerated capacitive scanning without CPU intervention. It supports ganged proximity sensing via internal analog bus routing and uses a 1.0–1.2 V internal analog reference for stable baseline tracking.

SmartSense_EMC_PLUS dynamically adjusts sensor parameters-including IDAC current, scan resolution, and noise filtering-during operation to maintain SNR across environmental drift and overlay thickness variations up to 15 mm (glass) or 5 mm (plastic). The driven shield function is implemented on five GPIOs with 100 pF load capacity at 3 MHz.

Key Specifications

Pinout & Package

48-pin QFN (7 mm × 7 mm, 0.5 mm pitch), thermally enhanced with exposed thermal pad. Pinout validated per Cypress Document 001-69257 Rev. *Q, Page 12.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY8C20666S-24LQXI, the CY8C20667S-24LQXI adds 6 sensing channels and doubles SRAM for complex slider interpolation; versus MTCH6302-I/SS, it integrates full firmware execution, runtime auto-tuning, and hardware-driven shield-eliminating host dependency and field recalibration.

Availability

CY8C20667S-24LQXI is available at Aetrix Electronics and suitable for home appliance control panels, industrial HMIs, medical device overlays, and automotive cabin proximity interfaces requiring stable component supply across extended product lifecycles.

Supply support for CY8C20667S-24LQXI 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

Cypress Semiconductor (now part of Infineon Technologies) designs programmable mixed-signal ICs for embedded sensing, connectivity, and control applications.

The CY8C20xx7/S series targets cost-sensitive, low-power capacitive user interfaces where runtime self-calibration, water tolerance, and metal-immune proximity are mandatory-not just optional-design requirements.

FAQ

What is the maximum overlay thickness supported by CY8C20667S-24LQXI?

The device supports up to 15 mm of glass or 5 mm of plastic overlay thickness, verified using its 0.1 pF sensitivity and CSD PLUS™ algorithm under IEC 61000-4-3 radiated immunity testing at 10 V/m. Performance is maintained across temperature ranges (–40 °C to +85 °C) and humidity levels up to 95% RH due to SmartSense_EMC_PLUS real-time baseline compensation.

Does CY8C20667S-24LQXI require external tuning components?

No external tuning components are required. The device uses an internal modulator capacitor (C_external on P4[7]) and programmable IDACs to set sensor gain and resolution. All calibration-including baseline, noise threshold, and finger threshold-is performed automatically by SmartSense_EMC_PLUS during runtime without host intervention or factory programming steps.

Can CY8C20667S-24LQXI operate from a single 3.3 V supply?

Yes. The device operates across 1.71 V to 5.5 V, including standard 3.3 V rails. At 3.3 V, it maintains full functionality: 24 MHz CPU speed, 31-sensor scanning, I²C at 400 kHz, and driven-shield output at 3 MHz. The internal LDO is bypassed in this configuration, improving power efficiency and reducing thermal load on the 48-pin QFN package.

How does the driven-shield feature improve water tolerance?

Driven-shield applies a buffered copy of the sensor signal to adjacent traces or ground planes, canceling parasitic capacitance caused by water films. On five designated GPIOs, it sustains 100 pF load at 3 MHz, enabling reliable operation under >5 mm continuous water layer-validated per IPX7 test conditions. This eliminates false triggers without requiring mechanical drainage structures or additional shielding layers.