Infineon Technologies CY8C4025LQI-S402T

Overview

CY8C4025LQI-S402T from Infineon is a 32-bit Arm® Cortex®-M0+ microcontroller with 32 KB flash, 4 KB SRAM, and integrated CAPSENSE™ capacitive sensing engine. It operates from 1.71 V to 5.5 V, supports Deep Sleep mode at 2.5 µA system current, and delivers best-in-class SNR (>5:1) for water-tolerant touch interfaces in consumer HMI applications.

For engineers reviewing the CY8C4025LQI-S402T datasheet, CY8C4025LQI-S402T pinout, CY8C4025LQI-S402T application, or CY8C4025LQI-S402T equivalent, key selection criteria include its programmable analog/digital blocks, dual SCB serial interfaces (I²C/SPI/UART), five TCPWM timers with comparator-triggered kill signals, and 36 GPIOs supporting CAPSENSE™ on any pin.

Technical Context

The device integrates a 48-MHz Arm® Cortex®-M0+ CPU with single-cycle multiply and a unified memory map. Its analog subsystem includes two low-power comparators active in Deep Sleep, a sigma-delta capacitive sensing block, and two programmable IDACs usable for sensor biasing or self-capacitance measurement.

Digital resources comprise five 16-bit TCPWM blocks supporting center-aligned PWM, edge-aligned timing, and pseudo-random modulation; two reconfigurable serial communication blocks (SCBs); and programmable logic blocks enabling Boolean operations directly on port I/O without CPU intervention.

Key Specifications

Pinout & Package

Package: 48-pin TQFP (7 mm × 7 mm, 0.5 mm pitch), RoHS-compliant, moisture-sensitive level 3.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY8C4025LQI-S402T, the S412T offers improved oscillator accuracy for timing-sensitive functions, while the STM32G031K8T6 lacks native capacitive sensing-requiring additional components or firmware overhead to replicate CAPSENSE™ performance and water tolerance.

Availability

CY8C4025LQI-S402T is available at Aetrix Electronics and suitable for consumer HMI, industrial panel controllers, home appliance interfaces, and portable medical devices requiring stable component supply and long-term lifecycle support.

Supply support for CY8C4025LQI-S402T 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 ICs, and embedded controllers, with global manufacturing and R&D infrastructure.

This part belongs to the PSoC™ 4000S product line, designed specifically for cost-sensitive, low-power embedded systems requiring integrated analog sensing, programmable logic, and robust capacitive touch in space-constrained applications.

FAQ

What development tools are supported for CY8C4025LQI-S402T?

Infineon officially supports ModusToolbox™ (cross-platform, Eclipse-based) and PSoC™ Creator (Windows-only, schematic-driven). Both provide CAPSENSE™ configuration tools, peripheral drivers, and code examples. MiniProg4 is the recommended programmer/debugger, and CY8CKIT-145-40XX serves as the reference evaluation kit with breadboard-compatible pin access.

Does CY8C4025LQI-S402T support hardware encryption or secure boot?

No. This variant does not include hardware cryptographic accelerators or secure boot ROM. It provides flash protection bits to prevent unauthorized read-out and debug disable functionality, but secure key storage, AES acceleration, or verified boot must be implemented externally or in software with appropriate risk assessment.

Can all 36 GPIOs be used simultaneously for CAPSENSE™?

No. While any GPIO can be assigned to CAPSENSE™, the sigma-delta sensing engine shares analog routing resources. Simultaneous use of all 36 pins as active sense electrodes exceeds hardware resource limits. Practical maximum is 24 electrodes with full resolution, depending on scan speed and SNR requirements per the CAPSENSE™ design guide.

Is the 48-MHz CPU frequency achievable across the full voltage range?

Yes, but only above 2.7 V supply. At 1.71–2.7 V, maximum CPU frequency is reduced to 24 MHz per the device electrical specifications. The IMO (internal main oscillator) is factory-trimmed to ±2% at 48 MHz, and automatic frequency scaling is not built-in-firmware must manage clock tree configuration based on operating voltage.