April 2014

DocID026226 Rev 1

1/17

UM1748

User manual

EVALSTPM34, EVALSTPM33, EVALSTPM32 evaluation board

Introduction

This user manual describes the EVALSTPM34, EVALSTPM33, EVALSTPM32 evaluation

board.

The STPM3x is an ASSP family of mixed signals designed for high accuracy measurement

of power and energy in power line systems using the Rogowski coil, current transformer or

shunt current sensors. According to p/n, the device has up to two voltages and two current

channels, for energy measurement in dual-phase and single-phase (with or without neutral

current monitoring) electricity metering systems.

The STPM3x devices provide instantaneous voltage and current waveforms and calculate

voltage and current RMS values, active, reactive and apparent powers and energies for

each channel. Moreover, they embed a full set of calibration and compensation parameters

which allow the meter to fit tight accuracy standards (EN 50470-x, IEC 62053-2x,

ANSI12.2x for AC watt meters). All calculated data, as well as configuration parameters, are

stored in internal 32-bit registers accessible through SPI or UART peripheral.

Three boards are available for evaluation purpose:

•

EVALSTPM34 board with 2 CT

•

EVALSTPM33 board with CT + shunt

•

EVALSTPM32 board with shunt

The main features of these boards are:

•

0.2% accuracy single-phase meter reference design

•

USB port for connection to the isolated hardware programmer STEVAL-IPE023V1 and

PC GUI

•

RS232 and UART isolated port for connection to PC GUI

•

SPI/UART switch for device peripheral selection

•

2x programmable LEDs on-board

•

Digital expansion to external system-on-chip or MCU

•

Power supply 3.3 V: external or through the STEVAL-IPE023V1 isolated USB board

•

IEC61000 standard compliant

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