Infineon Technologies CY8C4124FNI-S403T

Overview

CY8C4124FNI-S403T from Infineon is a programmable 32-bit Arm® Cortex®-M0+ microcontroller with 48 MHz CPU, 32 KB flash, 4 KB SRAM, integrated CAPSENSE™ capacitive sensing, 12-bit 1-Msps SAR ADC, and three reconfigurable serial communication blocks (I²C/SPI/UART). It supports deep-sleep operation at 2.5 µA and delivers best-in-class SNR (>5:1) for water-tolerant touch interfaces in industrial HMI and consumer control panels.

For engineers reviewing the CY8C4124FNI-S403T datasheet, CY8C4124FNI-S403T pinout, CY8C4124FNI-S403T application, or CY8C4124FNI-S403T equivalent, key selection criteria include its 36 GPIO with full CAPSENSE™/analog/digital reconfiguration, TCPWM kill-signal triggering for motor safety, SmartSense™ automatic tuning, and ModusToolbox™-supported development flow.

Technical Context

The device integrates a fixed-function Arm® Cortex®-M0+ core with programmable analog (two opamps, two comparators, IDACs) and digital (PLD logic, TCPWM, SCBs) subsystems routed via configurable interconnect. Its CAPSENSE™ sigma-delta engine operates independently of CPU load and maintains >5:1 SNR under wet conditions.

Clocking combines ±2% IMO, 32 kHz ILO, and external WCO for precision timing; power management enables Deep Sleep with active analog blocks and 2.5 µA system current. All 36 GPIO support programmable drive strength, slew rate, and CAPSENSE™ electrode assignment.

Key Specifications

Pinout & Package

Package: 40-pin QFN (6 × 6 mm, 0.5 mm pitch), thermally enhanced with exposed pad. Pin mapping validated per Infineon datasheet 002-00122 Rev. *Q, Section 3 "Pinouts".

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable MCU applications.

Compared with CY8C4124FNI-S403T, CY8C4024LQI-S403 trades TCPWM safety features and memory for lower unit cost, while STM32G031K8T6 shifts CAPSENSE™ implementation burden to external components and firmware - increasing BOM, layout complexity, and qualification effort.

Availability

CY8C4124FNI-S403T is available at Aetrix Electronics and suitable for industrial HMI, medical device interfaces, smart appliance controls, and automotive cabin modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for CY8C4124FNI-S403T 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

Infineon Technologies is a German semiconductor manufacturer specializing in power management, sensing, and microcontroller solutions for industrial, automotive, and IoT markets.

CY8C4124FNI-S403T belongs to the PSoC™ 4100S product line, designed specifically to integrate capacitive sensing, programmable analog, and Arm®-based control in a single chip for cost-sensitive, space-constrained human interface applications.

FAQ

Does CY8C4124FNI-S403T support USB connectivity?

No. The device does not include a USB PHY or controller. Communication is limited to its three SCBs (I²C, SPI, UART) and SWD debug interface. For USB host/device functionality, an external bridge IC or companion MCU is required.

What is the maximum operating temperature for this part?

The CY8C4124FNI-S403T is rated for industrial temperature range: –40°C to +85°C ambient. This is confirmed in Section 5.2.1 of the official datasheet (002-00122 Rev. *Q), with validated performance across the full range for GPIO, ADC, and CAPSENSE™ functions.

Can the SAR ADC perform simultaneous sampling on multiple channels?

No. The 12-bit SAR ADC uses a single sample-and-hold circuit and supports sequential conversion via hardware channel sequencing, but not true simultaneous sampling. Channel switching occurs in <1 µs, enabling pseudo-simultaneous acquisition for most sensor fusion use cases.

Is the exposed thermal pad on the QFN package electrically connected?

Yes. The exposed pad is internally connected to VSS and must be soldered to a solid ground plane for thermal dissipation and EMI suppression. Section 3.1 of the datasheet specifies it as "VSS Pad" and requires minimum 90% solder coverage for reliability.