Infineon Technologies CY8C20636A-24LQXIT

Overview

CY8C20636A-24LQXIT from Cypress Semiconductor is a programmable 1.8 V CapSense® controller with SmartSense™ auto-tuning, integrating an M8C 8-bit Harvard CPU (24 MHz max), 32 KB flash/2 KB SRAM, and dedicated hardware for capacitive sensing of up to 33 buttons or 6 sliders. It supports full-speed USB 2.0 (12 Mbps), I²C (up to 400 kHz), SPI (up to 12 MHz), and operates from 1.71 V to 5.5 V with deep sleep current as low as 0.1 µA - deployed in industrial HMI touch panels requiring EMC-robust, production-ready capacitive interfaces.

For engineers reviewing the CY8C20636A-24LQXIT datasheet, CY8C20636A-24LQXIT pinout, CY8C20636A-24LQXIT application, or CY8C20636A-24LQXIT equivalent, key selection criteria include SmartSense_EMC noise immunity, on-chip LDO PSRR, configurable GPIO sink capability (25 mA per pin), and USB/I²C/SPI coexistence in a single QFN-48 package.

Technical Context

The device implements a dedicated CapSense analog block with patented CSA_EMC and CSD sensing algorithms, enabling real-time auto-tuning via SmartSense_EMC to maintain signal-to-noise ratio across voltage, temperature, and overlay variations without firmware intervention. Its internal 1.2 V analog reference and global analog bus support ganged proximity sensing and direct connection of up to 33 sensor inputs.

It features four clock sources - 6/12/24 MHz IMO, 32 kHz ILO, external 32 kHz crystal, and external clock input - with independent clock gating for USB, CapSense, and system domains. The M8C core executes from flash with Read-While-Write EEPROM emulation and supports in-system programming for manufacturing flexibility.

Key Specifications

Pinout & Package

Package: 48-pin QFN (7 mm × 7 mm, 0.5 mm pitch), RoHS-compliant, exposed thermal pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MTCH101-I/ST and STM32F072CBT6, CY8C20636A-24LQXIT delivers production-ready capacitive performance out-of-box via hardware SmartSense_EMC, integrated USB, and deterministic scan timing - reducing time-to-certification by eliminating iterative layout and firmware tuning cycles.

Availability

CY8C20636A-24LQXIT is available at Aetrix Electronics and suitable for industrial HMI, medical device interfaces, home appliance keypads, and automotive cabin controls requiring stable component supply, long-term lifecycle assurance, and qualified RoHS-compliant QFN packaging.

Supply support for CY8C20636A-24LQXIT 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 - headquartered in San Jose, CA, with global manufacturing and support infrastructure.

CY8C20xx6A belongs to the CapSense® Express family, engineered specifically for production-grade capacitive touch applications where EMC robustness, zero-touch calibration, and rapid integration into legacy USB or I²C systems are mandatory.

FAQ

Does CY8C20636A-24LQXIT require external crystal for USB operation?

No. The device uses its internal 24 MHz IMO for USB clock generation, with automatic frequency calibration against the 32 kHz crystal or ILO. External crystal is optional and only required if precise sleep timer accuracy or enhanced EMI immunity is needed - USB remains fully functional using IMO alone.

Can all 33 GPIOs be used simultaneously as capacitive sensors?

Yes, up to 33 GPIOs can be configured as CapSense inputs, but actual count depends on package pin count and function allocation. The QFN-48 variant supports all 33 sensors - confirmed by Cypress datasheet Figure 18 (pinout for 48-pin QFN with USB) and Table 1 (sensor count mapping). No multiplexing or time-division sharing is required.

What is the maximum recommended overlay thickness for reliable touch detection?

With SmartSense auto-tuning enabled, the device reliably detects touches through up to 8 mm acrylic or 4 mm glass overlays - verified per AN73034 test methodology using standard 10 mm diameter electrodes. Performance remains stable across temperature and humidity when SmartSense_EMC is active.

Is PSoC Designer still supported for CY8C20636A-24LQXIT firmware development?

Yes. Cypress officially supports PSoC Designer v5.4 SP4 for CY8C20xx6A devices, including full CapSense configuration, SmartSense tuning wizard, and USB HID descriptor generation. While newer PSoC devices use PSoC Creator, CY8C20636A-24LQXIT retains full toolchain compatibility and downloadable libraries remain available from Infineon's archived resources portal.