Infineon Technologies CY8C20347-24LQXI

Overview

CY8C20347-24LQXI 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 current at 125 ms scan interval, and operates from –40 °C to +85 °C in a 48-pin QFN package.

For engineers reviewing the CY8C20347-24LQXI datasheet, CY8C20347-24LQXI pinout, CY8C20347-24LQXI application, or CY8C20347-24LQXI equivalent, key selection criteria include capacitive sensing channel count, SmartSense runtime auto-tuning behavior, I²C slave timing modes (50/100/400 kHz), driven-shield GPIO support, and low-power deep-sleep current (0.1 µA typical).

Technical Context

The device implements a dedicated CapSense analog block using Capacitive Sigma Delta PLUS (CSD PLUS™) sensing algorithm, enabling simultaneous scanning of up to 31 buttons or configurable ganged proximity sensors via internal analog mux bus. It integrates a 1.0–1.2 V internal analog reference and supports overlay thicknesses up to 15 mm (glass) or 5 mm (plastic).

SmartSense_EMC_PLUS Auto-Tuning dynamically adjusts sensor parameters-including IDAC current, scan resolution, and noise filtering thresholds-during runtime to maintain stable performance across environmental drift, PCB process variation, and overlay aging. The driven-shield function on five GPIOs enables robust water tolerance and metal-immune proximity detection.

Key Specifications

Pinout & Package

48-pin QFN (7 mm × 7 mm, 0.5 mm pitch), thermally enhanced with exposed thermal pad. Package meets JEDEC MO-220, RoHS-compliant, moisture sensitivity 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 CY8C21434-24LFXI, CY8C20347-24LQXI uniquely supports 31-input scanning with runtime SmartSense tuning and driven-shield GPIOs-critical for high-reliability, variable-overlay, and industrial-grade proximity applications.

Availability

CY8C20347-24LQXI is available at Aetrix Electronics and suitable for home appliance control panels, industrial HMI interfaces, medical device keypads, and smart building occupancy sensors requiring stable component supply, long-lifecycle support, and automotive-grade reliability validation.

Supply support for CY8C20347-24LQXI 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 R&D centers and ISO 9001-certified manufacturing.

This device belongs to the PSoC® 1 CapSense family-engineered specifically for self-contained, low-power capacitive touch and proximity sensing in consumer, industrial, and medical UIs without external signal conditioning.

FAQ

Does CY8C20347-24LQXI support I²C multi-master operation?

No. The integrated I²C peripheral operates exclusively as a slave device with configurable address matching and clock-stretch capability. It does not implement master arbitration or bus control logic required for multi-master systems. External I²C masters must coordinate access to avoid collisions.

Can the driven-shield feature be used on all 34 GPIOs?

No. Driven-shield functionality is hardware-assigned to only five specific GPIOs: P0[0], P0[1], P0[2], P0[3], and P0[4]. These pins support synchronized shield drive waveform generation synchronized to the CSD modulator clock, and cannot be reassigned to other pins via firmware.

What is the maximum overlay thickness supported for proximity sensing?

The device achieves reliable proximity detection through up to 15 mm of glass or 5 mm of plastic overlay when configured with SmartSense_EMC_PLUS and driven-shield enabled. Performance beyond these limits depends on electrode size, spacing, and ambient EMI-actual range must be validated per mechanical design.

Is PSoC Designer™ still actively supported for this device?

Yes. Cypress maintains legacy toolchain support for CY8C20xx7 devices via PSoC Designer 5.4 SP4, including full component library, code generation, and debugger integration. Infineon provides archived downloads and known-issue documentation through the official PSoC 1 resources portal.