STMicroelectronics EVALSTPM34

Overview

EVALSTPM34 from STMicroelectronics is an evaluation board for the STPM34 high-accuracy polyphase energy metering ASSP, designed to interface with Rogowski coils, current transformers, or shunt sensors in AC watt-hour meters. It supports dual-channel voltage/current measurement, delivers <0.1% active power error over 5000:1 dynamic range, features four 24-bit sigma-delta ADCs, and operates across –40 °C to +105 °C for utility-grade metering applications.

For engineers reviewing the EVALSTPM34 datasheet, EVALSTPM34 pinout, EVALSTPM34 application, or EVALSTPM34 equivalent, this board enables rapid validation of STPM34's energy calculation accuracy, zero-crossing detection, UART/SPI communication, programmable LED/INT outputs, and dual-reference voltage calibration under real-world line conditions (50/60 Hz, up to 90 A).

Technical Context

The EVALSTPM34 implements the full signal chain of the STPM34 IC: two chopper-stabilized PGLNAs feed four independent 24-bit 2nd-order sigma-delta modulators (OSF = 4 MHz), followed by decimation, phase compensation, and a hardwired DSP engine performing RMS, active/reactive/apparent energy, and sag/swell monitoring. The board routes all critical analog inputs (VIP1/VIN1/IIP1/IIN1/VIP2/VIN2/IIP2/IIN2) with matched trace lengths and low-noise layout.

It exposes both UART and SPI interfaces with configurable CRC, supports dual precision references (1.18 V, 30 ppm/°C TC), integrates LDOs for 3.0 V (VDDA) and 1.2 V (VDDD), and provides hardware-enabling features including ZCR output, EN reset control, and SYN synchronization - all aligned to EN 50470-x and IEC 62053-2x compliance testing requirements.

Key Specifications

Availability

EVALSTPM34 is available at Aetrix Electronics and suitable for utility meter development, smart grid sensor prototyping, and EN 50470-compliant energy analyzer design requiring stable component supply and production-ready reference hardware.

Supply support for EVALSTPM34 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, Switzerland, with R&D and manufacturing operations across Europe, Asia, and the Americas, serving automotive, industrial, power, and smart metering markets.

The STPM3x product line is a dedicated ASSP family for high-accuracy electricity metering ICs - engineered to replace discrete metrology signal chains with integrated analog front-end, DSP, and communication logic in a single QFN package.

FAQ

Does EVALSTPM34 include the STPM34 IC pre-soldered and functional?

Yes. EVALSTPM34 ships with the STPM34 IC (QFN32L, 5×5 mm) fully assembled and tested. All analog input paths, reference circuits, LDOs, crystal oscillator (16 MHz), and digital interfaces are operational out-of-box. Firmware is preloaded to enable immediate UART/SPI communication and energy register readout via ST's eDesignSuite or custom host software.

What external components must be added to use EVALSTPM34 with a shunt current sensor?

A calibrated shunt resistor (e.g., 0.3 mΩ, ±0.5%, 50 ppm/°C) and matching Kelvin connections to IIP1/IIN1 and IIP2/IIN2 are required. Voltage divider networks (e.g., 1:1650 ratio for 230 V RMS) must be connected to VIP1/VIN1 and VIP2/VIN2. No additional op-amps or filters are needed - the board's PGLNAs and ADCs handle full signal conditioning.

Can EVALSTPM34 be used to validate compliance with IEC 62053-22 Class 0.2 accuracy?

Yes. EVALSTPM34 enables full characterization of STPM34's metrology performance under IEC 62053-22 test conditions: harmonic distortion (up to 40th), phase angles (0° to ±90°), frequency variation (45–65 Hz), and dynamic load steps. Its low-noise layout, calibrated references, and dual-channel isolation meet Class 0.2 active/reactive energy error limits (<±0.2%) when paired with certified source equipment.

Is the EVALSTPM34 compatible with ST's SPIMON or eMeter software tools?

Yes. EVALSTPM34 is natively supported by ST's eMeter GUI (v3.2+) and SPIMON diagnostic tool. These utilities provide real-time waveform capture (voltage/current ADC outputs), energy register monitoring, gain/offset calibration wizard, and error histogram analysis - all via USB-to-UART bridge or direct SPI connection without additional adapters.