Infineon Technologies CY8C20447-24LQXI

Overview

CY8C20447-24LQXI 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), 8 KB flash, 1 KB SRAM, and dedicated hardware for capacitive sensing across 31 buttons, 6 sliders, and proximity sensors. It operates from 1.71–5.5 V, achieves 28 µA/sensor average current at 125 ms scan interval, and supports driven shield on five GPIOs for water-tolerant and metal-immune touch interfaces in industrial HMI panels.

For engineers reviewing the CY8C20447-24LQXI datasheet, CY8C20447-24LQXI pinout, CY8C20447-24LQXI application, or CY8C20447-24LQXI equivalent, key selection criteria include its CSD PLUS™ sigma-delta sensing algorithm (0.1 pF sensitivity), SmartSense_EMC_PLUS runtime auto-tuning, I2C slave (up to 400 kHz), 48-pin QFN package with 34 GPIOs, and integrated 10-bit ADC with internal reference.

Technical Context

The device implements a dedicated CapSense analog block with patented Capacitive Sigma Delta PLUS (CSD PLUS™) sensing engine, enabling high-SNR measurement without external components. Its hardware-accelerated scanning supports up to 31 sensing inputs with configurable resolution and scan speed, while the QuietZone™ architecture provides robust immunity against conducted/radiated noise.

SmartSense_EMC_PLUS operates autonomously during runtime-dynamically adjusting IDAC, modulation clock, and baseline tracking parameters per sensor to maintain optimal SNR across temperature, humidity, and overlay drift. The internal 1 V/1.2 V analog reference and low-dropout regulator ensure stable sensing under varying supply conditions.

Key Specifications

Pinout & Package

Package: 48-pin QFN (7 mm × 7 mm, 0.5 mm pitch), RoHS-compliant, moisture-sensitive level 3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MTCH101-I/ST and STM32F072CBT6, CY8C20447-24LQXI delivers deterministic, hardware-accelerated sensing with zero firmware tuning effort, making it optimal for volume production of robust, certified touch interfaces where time-to-market and reliability outweigh raw MCU performance or lowest unit cost.

Availability

CY8C20447-24LQXI is available at Aetrix Electronics and suitable for industrial HMI panels, home appliance interfaces, medical device keypads, and automotive cabin controllers requiring stable component supply and long-term lifecycle support.

Supply support for CY8C20447-24LQXI 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 control, sensing, and connectivity applications, with global manufacturing and quality certifications including ISO 9001 and AEC-Q100.

CY8C20xx7/S is part of Cypress's CapSense® controller product line, engineered specifically for high-reliability, low-power capacitive touch and proximity sensing in harsh EMI environments without external tuning components.

FAQ

What is the maximum overlay thickness supported by CY8C20447-24LQXI?

The device supports up to 15 mm of glass or 5 mm of plastic overlay thickness, enabled by its 0.1 pF sensing sensitivity and CSD PLUS™ algorithm's high SNR performance. This capability is verified under IEC 61000-4-3 radiated immunity testing at 10 V/m and confirmed across production units with standard 2.2 nF modulator capacitors and driven-shield configurations.

Does CY8C20447-24LQXI require external tuning components for CapSense operation?

No external tuning components are required. The SmartSense_EMC_PLUS auto-tuning engine dynamically adjusts IDAC, modulation clock, and baseline tracking in real time. Only a single external 2.2 nF modulator capacitor (connected to MOD_CAP pin) and optional 32 kHz crystal (for precise sleep timing) are needed-no resistors, trimmers, or calibration firmware steps.

Can CY8C20447-24LQXI operate in deep sleep mode while maintaining proximity wake-up capability?

Yes. In deep sleep mode (0.1 µA typical), the device retains I2C address match wake-up and hardware-based proximity interrupt capability via the CapSense block. Wake-up occurs within 100 µs of valid proximity event detection, with no CPU involvement required until interrupt service begins.

How many GPIOs support driven shield functionality, and what is the maximum load capacitance?

Five GPIOs (P0[0]–P0[4]) are hardware-configurable as driven shields. Each supports up to 100 pF load capacitance at 3 MHz operation, enabling long trace routing and robust water tolerance. Shield drive amplitude matches VDD and is synchronized to the CSD clock to maximize common-mode noise rejection.