STMicroelectronics STEVAL-IFP023V1

Overview

STEVAL-IFP023V1 from STMicroelectronics is a 16-bit digital input evaluation board built around two CLT01-38S4 high-speed protected digital termination arrays, supporting IEC 61131-2 Type 1 and Type 3 industrial inputs, daisy-chained via SPI, with on-board LED status indicators and integrated overvoltage/ESD protection.

For engineers reviewing the STEVAL-IFP023V1 datasheet, STEVAL-IFP023V1 pinout, STEVAL-IFP023V1 application, or STEVAL-IFP023V1 equivalent, this board enables rapid validation of robust digital input interfaces in PLCs, distributed I/O modules, and industrial controllers under real-world EMC stress conditions including ±3 kV EFT and 2 kV surge.

Technical Context

The board implements dual CLT01-38S4 devices in daisy-chain SPI topology, delivering 16 isolated digital input channels with per-channel current limiting, thermal/voltage alarms, and checksum verification. Each CLT01-38S4 integrates a voltage regulator, termination resistors, and protection circuitry compliant with IEC 61000-4-2 (8 kV air), -4-4 (±3 kV), and -4-5 (2 kV).

SPI communication operates at high frequency to support fast polling of input states, while galvanic isolation is achieved using ACPL-K73L optocouplers on MISO, MOSI, SCK, and nCS lines - enabling safe interface with microcontrollers operating at different ground domains.

Key Specifications

Availability

STEVAL-IFP023V1 is available at Aetrix Electronics and suitable for industrial PLC design, distributed I/O module development, and factory automation controller prototyping requiring stable component supply and validated EMC performance.

Supply support for STEVAL-IFP023V1 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing microcontrollers, power management ICs, analog & MEMS devices, and industrial interface solutions.

The STEVAL-IFP023V1 belongs to ST's Industrial Evaluation Board portfolio, developed specifically to accelerate adoption of its protected digital input arrays in harsh industrial environments with stringent safety and immunity requirements.

FAQ

What is the primary function of the CLT01-38S4 chips on this board?

The CLT01-38S4 chips serve as protected digital input terminators, providing integrated current limiting, overvoltage clamping, thermal monitoring, and SPI-accessible status registers for up to eight 16–253 V industrial inputs per device. They eliminate discrete protection components and reduce PCB area while meeting IEC 61131-2 compliance.

Does the board provide galvanic isolation between field-side inputs and MCU-side SPI?

Yes - the board uses ACPL-K73L high-speed optocouplers on all four SPI lines (MISO, MOSI, SCK, nCS), achieving reinforced isolation rated to 3750 V_RMS. This ensures safe communication between the high-voltage field side (up to 253 V) and low-voltage microcontroller domain without shared ground references.

Can the STEVAL-IFP023V1 be used with non-ST microcontrollers?

Yes - the board communicates exclusively via standard 4-wire SPI (mode 0, CPOL=0, CPHA=0) and requires no proprietary firmware or drivers. Any microcontroller with SPI master capability and 3.3 V I/O can interface directly, provided timing constraints (e.g., min. t_CS hold time) specified in the CLT01-38S4 datasheet are met.

Are the input channels individually configurable for Type 1 or Type 3 operation?

No - the board is pre-configured for IEC 61131-2 Type 3 (15–253 V) operation using fixed external resistor networks per channel. Type 1 (15–30 V) support would require hardware modification to adjust termination values, as the CLT01-38S4 itself supports both types but the board layout fixes the configuration.