Infineon Technologies CY8C20237-24LKXIT

Overview

CY8C20237-24LKXIT from Cypress Semiconductor is a 1.8 V CapSense® capacitive touch controller with SmartSense™ auto-tuning, featuring 31 sensing inputs (buttons), 6 sliders, and proximity sensing capability. It integrates an M8C 8-bit Harvard-architecture CPU (24 MHz max), 8 KB flash, 1 KB SRAM, and a dedicated CSD PLUS™ sigma-delta sensing engine delivering 0.1 pF sensitivity-enabling glass overlays up to 15 mm thick in industrial HMI panels.

For engineers reviewing the CY8C20237-24LKXIT datasheet, CY8C20237-24LKXIT pinout, CY8C20237-24LKXIT application, or CY8C20237-24LKXIT equivalent, key selection criteria include its integrated SmartSense_EMC_PLUS runtime auto-tuning, driven-shield support on five GPIOs for water-tolerant designs, I²C slave interface (up to 400 kHz), and ultra-low deep-sleep current (0.1 µA typical).

Technical Context

The device implements a dedicated CapSense analog subsystem with programmable CSD PLUS™ sigma-delta modulation, using internal 1.0 V or 1.2 V reference and configurable CSCLK derived from IMO or external sources. Sensing is performed across up to 31 GPIOs with hardware-accelerated scan sequencing and automatic baseline tracking.

Its M8C core executes firmware in flash while managing real-time sensor polling, I²C/SPI communication, and timer-driven wake-up events. The analog mux bus enables flexible routing of sensor signals to comparators or ADC, supporting ganged proximity detection and shield driver control without external components.

Key Specifications

Pinout & Package

48-pin QFN (7 mm × 7 mm, 0.5 mm pitch) with exposed thermal pad. Pin functions validated per Cypress Document #001-69257 Rev. *Q, pages 12 and 33–36.

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 AT42QT2120-MMHR, CY8C20237-24LKXIT provides full embedded firmware execution, adaptive SmartSense tuning, and scalable sensing channel count-making it suitable for complex, field-deployed HMIs where long-term reliability and zero-touch calibration are mandatory.

Availability

CY8C20237-24LKXIT is available at Aetrix Electronics and suitable for industrial HMI panels, medical device keypads, consumer appliance interfaces, and automotive cabin controls requiring stable component supply across extended product lifecycles.

Supply support for CY8C20237-24LKXIT 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 focus on reliability and system integration.

This device belongs to the CY8C20xx7/S CapSense® controller family, engineered specifically for robust, self-calibrating capacitive touch interfaces in harsh environments-including moisture, EMI, and wide temperature ranges.

FAQ

What is the maximum overlay thickness supported by CY8C20237-24LKXIT?

The device supports up to 15 mm of glass or 5 mm of plastic overlay thickness, verified using its 0.1 pF sensing sensitivity and CSD PLUS™ algorithm under standard lab conditions per Cypress Application Note AN71815. Performance depends on electrode size, trace routing, and grounding layout-designers must follow recommended PCB stack-up guidelines in the Hardware Design Guide.

Does CY8C20237-24LKXIT require external tuning components?

No external tuning components are required. All capacitive sensing parameters-including IDAC current, scan resolution, and baseline tracking-are dynamically adjusted by SmartSense_EMC_PLUS during runtime. The only external component needed is the modulator capacitor (C_external) on P0[1] or P0[3], typically 2.2 nF ±10%, as specified in Section 3.2 of the datasheet.

Can CY8C20237-24LKXIT operate from a single 3.3 V supply?

Yes-it operates across 1.71 V to 5.5 V, including standard 3.3 V rails. At 3.3 V, the internal LDO can be bypassed to directly power the analog sensing block, improving power efficiency. The I²C interface remains compatible with 3.3 V logic levels, and GPIOs support 5 V-tolerant inputs when configured appropriately per DC GPIO specifications.

How many simultaneous touch points does CY8C20237-24LKXIT support?

The device supports up to 31 independent capacitive sensing inputs but does not implement multi-touch coordinate decoding (e.g., X/Y position interpolation). It detects presence, proximity, and gesture direction on sliders-but reports only binary or delta-count values per channel. Full multi-touch position calculation must be implemented externally in the host MCU or application firmware.