STMicroelectronics EVALSTPM32

Overview

EVALSTPM32 from STMicroelectronics is a single-phase energy metering evaluation board based on the STPM32 metrology IC, featuring shunt-based current sensing, 0.2% accuracy, 140–300 V_RMS input voltage range, 5/100 A_RMS current range, and compliance with IEC61000 standards for EMC robustness. It supports isolated RS232 and USB (via STEVAL-IPE023V1) PC interface for configuration and real-time active/reactive power monitoring in utility-grade metering development.

For engineers reviewing the EVALSTPM32 datasheet, EVALSTPM32 pinout, EVALSTPM32 application, or EVALSTPM32 equivalent, this board enables rapid validation of STPM32-based metering firmware, calibration workflows, isolation interface design, and digital expansion to external SoCs via SPI/UART-critical for class 0.2 meter certification and field-deployable prototype testing.

Technical Context

The board implements a complete single-phase metrology signal chain: analog front-end with precision shunt sensing (R_S = 0.003 Ω), 16-bit sigma-delta ADCs, on-chip reference (1.22 V), and digital processing core optimized for active/reactive energy computation per IEC62053-21/22. It includes galvanic isolation on both RS232 (MAX3232 + Si8621) and USB (STEVAL-IPE023V1) paths.

Hardware configurability is provided via DIP switch (SW1) for SPI/UART peripheral selection at power-up, dual programmable LEDs for real-time power indication, and jumper-enabled digital I/O expansion (J5) and metrology sensor selection (shunt vs. CT). The 16 MHz crystal (Y1) drives the STPM32's internal PLL for stable timing.

Key Specifications

Availability

EVALSTPM32 is available at Aetrix Electronics and suitable for utility meter prototyping, smart grid edge node development, and energy monitoring system validation requiring stable component supply, traceable sourcing, and long-term BOM continuity.

Supply support for EVALSTPM32 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 ICs, sensors, and analog/metrology solutions for industrial, automotive, and consumer applications.

The EVALSTPM32 belongs to ST's energy metering evaluation platform family, engineered specifically to accelerate development and certification of IEC62053-compliant single-phase meters using STPM32 metrology ICs.

FAQ

What software tools are required to operate EVALSTPM32?

The board requires ST's official STPM32 Evaluation GUI, distributed with the STEVAL-IPE023V1 USB programmer tool. This GUI enables real-time register read/write, calibration coefficient loading, LED behavior configuration, and active/reactive power waveform visualization over isolated RS232 or USB.

Can EVALSTPM32 be used with current transformers instead of shunts?

Yes - the board supports both shunt and current transformer (CT) current sensing. Jumper configuration J9 selects CT mode (populate L2/L3/L4 and omit RS1), while shunt mode uses the onboard BKW-M-R0003-5.0 shunt resistor (RS1) with associated filtering components.

Does EVALSTPM32 provide calibrated energy output signals?

No - it outputs raw metrology data (e.g., instantaneous voltage/current, computed energy registers) via SPI/UART or GUI. Calibration must be performed by the user using known reference sources and ST's recommended procedure in AN4327 and the STPM32 datasheet.

Is external power required when using STEVAL-IPE023V1?

No - the STEVAL-IPE023V1 USB interface provides regulated 3.3 V power to EVALSTPM32 through J3. An external DC supply (via J7) is only needed when operating standalone or with RS232-only communication.