STMicroelectronics EVALSTPM-3PHISO

Overview

EVALSTPM-3PHISO from STMicroelectronics is a three-phase electricity meter evaluation board based on the STPMS2 sigma-delta modulator, STISO621W galvanic isolator, and STM32F413RH microcontroller. It delivers Class 0.5 active/apparent power accuracy per IEC 62053-22, Class 1 reactive power accuracy per IEC 62053-21, 2.5 kHz measurement bandwidth, 200 µs sample decimation, and 6 kV phase-to-phase isolation for utility-grade energy metering.

For engineers reviewing the EVALSTPM-3PHISO datasheet, EVALSTPM-3PHISO pinout, EVALSTPM-3PHISO application, or EVALSTPM-3PHISO equivalent, this board enables rapid validation of shunt-based three-phase metrology architectures compliant with EN 50470-x, IEC 62053-2x, and ANSI C12.2x standards - especially for firmware calibration, LED pulse output timing, and isolated bitstream processing via DFSDM.

Technical Context

The board implements real-time metrology computation on a 200 µs basis using the STM32F413RH's DFSDM filters to decode six synchronized sigma-delta bitstreams (three voltage + three current) from the STPMS2 modulators. Each bitstream is oversampled at 4 MHz and multiplexed onto shared pins, then isolated via STISO621W with <3 ns pulse distortion and 100 Mbps throughput.

Calibration includes amplitude, power offset, and sample offset correction for DC measurement; high-pass filtering is configurable for DC rejection. Line period, phase shift, RMS, and optional THD are computed per phase, with phase voltage delays supported for advanced synchronization analysis.

Key Specifications

Availability

EVALSTPM-3PHISO is available at Aetrix Electronics and suitable for utility meter development, smart grid sensor prototyping, and industrial energy monitoring systems requiring stable component supply and certified metrology reference design.

Supply support for EVALSTPM-3PHISO 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, analog ICs, power devices, and sensors for industrial, automotive, and consumer applications.

This board belongs to ST's metering evaluation platform family, engineered specifically to accelerate compliance-certified three-phase energy measurement system development using shunt-based sensing and ARM Cortex-M metrology firmware stacks.

FAQ

What standards does EVALSTPM-3PHISO support for certification?

EVALSTPM-3PHISO complies with EN 50470-x, IEC 62053-21 (Class 1 reactive), IEC 62053-22 (Class 0.5 active/apparent), and ANSI C12.2x standards. Its hardware layout, isolation, and firmware algorithms are pre-validated to meet test requirements for type approval - including temperature drift, linearity, and harmonic immunity tests defined in those documents.

How is isolation implemented between measurement and host domains?

Isolation uses STISO621W dual-channel digital isolators rated for 6 kV surge withstand and 8 mm creepage/clearance. These isolate the STPMS2 bitstream outputs from the STM32F413RH's DFSDM inputs, enabling safe 100 Mbps data transfer with <3 ns pulse distortion - critical for preserving sigma-delta timing integrity across domains.

Can the board measure DC or DC-offset waveforms?

Yes - the firmware supports a configurable high-pass filter to reject DC components, and full DC calibration (amplitude, power offset, sample offset) is implemented. This allows accurate metrology on waveforms with DC bias, such as those found in PV-inverter fed grids or certain industrial drives.

What metrology outputs are accessible via USB virtual COM port?

The USB interface exposes real-time computed values including per-phase active/reactive/apparent power, energy counters, RMS voltage/current, THD, line period, phase shift, and calibration registers. Shell commands enable reading, writing, and triggering full-system calibration - no JTAG or additional tools required for field tuning.