PSoC 4 CY8C4125 — what you get with the Cortex-M0+ at 24 MHz
The Infineon CY8C4125FNI-S423T is a PSoC 4 MCU from the CY8C4100S series, built around an ARM Cortex-M0+ core running at 24 MHz. The part integrates a dense analog front end: 16-channel 10-bit slope ADC, 16-channel 12-bit SAR ADC, and two IDACs — enough to handle multi-sensor arrays or CapSense electrode scanning without external muxing. Internal oscillator means no external crystal for the core clock, saving BOM cost and board area.
24 MHz core — what it handles and what it doesn't
The 24 MHz Cortex-M0+ is a deliberate choice for power-sensitive, deterministic control loops — think capacitive touch scanning, sensor polling, and simple protocol bridging. It is not a DSP workhorse; the CY8C4245LQI-483 runs at 48 MHz with the same Cortex-M0 core if you need double the throughput for FFT or faster serial throughput. The trade-off is current draw: the 24 MHz part sips less in active mode, which matters for battery-powered panels or wireless sensor nodes where every milliamp counts.
Infineon lists the CY8C4125FNI-S423T as Active. For a production BOM that already qualifies this MCU, there is no urgency to requalify a replacement — the supply outlook is stable.
The 85°C ceiling is the standard industrial limit; if your design needs 105°C or 125°C junction temperature, you would step up to the automotive-grade PSoC 4 variants.