Infineon Technologies CY8C4125LQI-S423

Overview

CY8C4125LQI-S423 from Infineon is a programmable 32-bit Arm® Cortex®-M0+ microcontroller with 48 MHz CPU, 64 KB flash, 8 KB SRAM, integrated CAPSENSE™ capacitive sensing, and reconfigurable analog/digital blocks. It supports deep-sleep operation at 2.5 µA, features three reconfigurable serial communication blocks (I²C/SPI/UART), and delivers 12-bit 1-Msps SAR ADC performance for embedded human-interface and sensor-fusion applications.

For engineers reviewing the CY8C4125LQI-S423 datasheet, CY8C4125LQI-S423 pinout, CY8C4125LQI-S423 application, or CY8C4125LQI-S423 equivalent, key selection considerations include its 48LD TQFP package, programmable GPIO drive modes, SmartSense auto-tuning for water-tolerant touch, TCPWM kill-signal triggering for motor control, and ModusToolbox™ software integration for rapid CAPSENSE™ development.

Technical Context

The device integrates a fixed-function Arm® Cortex®-M0+ core with configurable analog peripherals including two opamps supporting high-drive external and high-bandwidth internal modes, plus two low-power comparators that remain active in Deep Sleep. Its analog subsystem includes a 12-bit SAR ADC with channel sequencer and signal averaging, and a dedicated 10-bit sigma-delta CapSense ADC with >5:1 SNR.

Digital resources include five 16-bit TCPWM blocks supporting center-aligned PWM and quadrature decoding, three SCBs enabling runtime-reconfigurable I²C/SPI/UART, and programmable logic blocks for Boolean operations on port signals - all routed via automatic interconnect fabric without fixed signal paths.

Key Specifications

Pinout & Package

This device uses a 48-lead TQFP (Thin Quad Flat Package) with 0.5 mm pitch and exposed thermal pad. Pin assignments are validated per Infineon's official pinout diagram for CY8C4125LQI-S423 (Rev. *Q, p.16).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar programmable microcontroller with integrated capacitive sensing applications.

Compared with CY8C4125LQI-S423, CY8C4025LQI-S402 trades memory and timing features for lower unit cost, while STM32G031K8T6 shifts CapSense implementation burden to firmware and external components - making CY8C4125LQI-S423 optimal for time-to-market-critical, touch-centric embedded systems.

Availability

CY8C4125LQI-S423 is available at Aetrix Electronics and suitable for industrial HMI, medical front panels, and smart home thermostats requiring stable component supply, long-term lifecycle assurance, and qualified automotive-grade traceability.

Supply support for CY8C4125LQI-S423 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, automotive MCUs, and secure microcontrollers, with global R&D and manufacturing infrastructure.

CY8C4125LQI-S423 belongs to the PSoC™ 4100S product line - designed specifically for cost-sensitive, touch-enabled embedded systems requiring seamless integration of analog sensing, digital control, and low-power operation.

FAQ

Does CY8C4125LQI-S423 support USB connectivity?

No, CY8C4125LQI-S423 does not include a USB PHY or controller. It relies on external USB-to-UART bridges or host-side USB gateways for connectivity. Its three SCBs support only I²C, SPI, and UART protocols - confirmed in the "Serial Communication Block" section of the datasheet (Rev. *Q, p.14).

What is the maximum operating temperature for this device?

CY8C4125LQI-S423 is rated for industrial temperature range: –40 °C to +85 °C. This specification is defined in Section 5.2 ("Device Level Specifications") of the official datasheet (Rev. *Q, p.22) and applies across all supply voltages and functional modes.

Can the SAR ADC perform simultaneous sampling on multiple channels?

No, the 12-bit SAR ADC uses a single sample-and-hold circuit and sequences channels sequentially via hardware channel sequencer. Simultaneous sampling is not supported; however, the sequencer achieves ≤1 µs inter-channel delay with signal averaging - sufficient for most multi-sensor synchronization needs.

Is the WCO (watch crystal oscillator) mandatory for real-time clock functionality?

Yes, the 32.768 kHz watch crystal oscillator (WCO) is required for accurate RTC operation and low-power wake-up timing. While the internal 32 kHz ILO is available, its ±50% accuracy makes it unsuitable for timekeeping; the WCO provides ±20 ppm stability - verified in Section 2.2.5 of the datasheet (Rev. *Q, p.12).