Infineon Technologies CY8C20636AN-24LTXI

Overview

CY8C20636AN-24LTXI from Cypress Semiconductor is a programmable 1.8 V CapSense® controller with SmartSense™ auto-tuning, featuring an M8C 8-bit Harvard-architecture CPU (24 MHz max), 8 KB flash/1 KB SRAM, and support for up to 33 capacitive buttons or 6 sliders. It integrates full-speed USB 2.0 (12 Mbps), I²C slave (up to 400 kHz), SPI, three 16-bit timers, and a 10-bit ADC - deployed in human-interface applications such as touch-enabled industrial HMIs and consumer appliance control panels.

For engineers reviewing the CY8C20636AN-24LTXI datasheet, CY8C20636AN-24LTXI pinout, CY8C20636AN-24LTXI application, or CY8C20636AN-24LTXI equivalent, key selection criteria include SmartSense_EMC noise immunity, low-power operation (28 µA/sensor @ 125 ms scan interval), USB interface capability, GPIO configuration flexibility (36 total, dual-mode analog/digital), and QFN-48 package compatibility with 33-sensor layouts.

Technical Context

The device implements a dedicated hardware CapSense block with patented CSA_EMC and CSD sensing algorithms, enabling real-time sensor calibration without host firmware intervention. Its SmartSense_EMC algorithm dynamically adjusts baseline, threshold, and IDAC settings to maintain stable button detection under EMI stress, including conducted/radiated noise per FCC/CE requirements.

It operates across 1.71–5.5 V with multiple clock sources: 6/12/24 MHz IMO, 32 kHz ILO, external crystal, or external clock input. The internal LDO provides regulated analog supply (1.8/2.5/3.0 V) with high PSRR, while the analog mux bus enables ganged proximity sensing via shared reference and comparator paths.

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 MTCH6302-I/ST and STM32F072CBT6, CY8C20636AN-24LTXI delivers turnkey CapSense performance with zero-tuning deployment, integrated USB HID, and hardware-level EMI resilience - reducing time-to-market by eliminating sensor characterization and firmware validation cycles.

Availability

CY8C20636AN-24LTXI is available at Aetrix Electronics and suitable for industrial HMI, home appliance control, medical touch interfaces, and USB-reprogrammable consumer remotes requiring stable component supply and long-term lifecycle assurance.

Supply support for CY8C20636AN-24LTXI 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 system-on-chip solutions for embedded control, connectivity, and human interface applications.

The CY8C20xx6A family targets cost-sensitive, low-power capacitive touch systems - delivering integrated analog sensing, USB connectivity, and auto-tuning intelligence in a single chip to replace discrete microcontrollers, ADCs, and touch controllers.

FAQ

What is the maximum number of capacitive sensors supported by CY8C20636AN-24LTXI?

The CY8C20636AN-24LTXI supports up to 33 capacitive buttons or 6 sliders, enabled by its 36 GPIOs (33 for sensing, 2 for I²C, 1 for modulator capacitor). This matches the QFN-48 package variant specified in the CY8C20XX6A/S datasheet Rev. *Y, page 17. Sensor count is constrained by physical pin count and internal analog routing resources-not firmware limits.

Does CY8C20636AN-24LTXI require external components for USB functionality?

No external components are required for full-speed USB 2.0 operation. The device integrates a compliant USB transceiver with on-die termination resistors and internal pull-up/pull-down logic. Only standard USB Type-A or Micro-B receptacle and ESD protection diodes (recommended per USB-IF guidelines) are needed on the PCB - no external PHY, magnetics, or series resistors.

How does SmartSense_EMC differ from standard SmartSense auto-tuning?

SmartSense_EMC extends baseline SmartSense with a proprietary algorithm that actively monitors high-frequency noise on sensor lines and dynamically adjusts IDAC drive strength, scan timing, and filtering coefficients to suppress conducted/radiated EMI. Unlike standard SmartSense-which optimizes for environmental drift-SmartSense_EMC specifically targets FCC/CE compliance margins in electrically noisy environments like kitchen appliances and industrial controls.

Can CY8C20636AN-24LTXI operate from a single 3.3 V supply without level-shifting?

Yes. The device operates across 1.71–5.5 V, so a single 3.3 V supply powers both VDD (digital core) and VDDA (analog domain) simultaneously. However, best practice recommends separating VDDA and using the internal LDO for improved PSRR - especially when 3.3 V is derived from a noisy switcher. The LDO can be configured to output 1.8 V, 2.5 V, or 3.0 V to optimize CapSense SNR.