EVALSTPM-3PHISO Data brief Three-phase full shunt electricity meter evaluation board based on STPMS2, STISO621W and STM32F413RH Features Compliant to EN 50470-x, IEC 62053-2x, ANSI12.2x standard requirements for AC watt meters Active wideband, active fundamental, reactive and apparent power/energy calculation for each phase and cumulative Accuracy Class 0.5 according to IEC 62053-22 on 3-ph active/apparent power measurement Accuracy Class 1 according to IEC 62053-21 on 3-ph reactive power measurement 6 channels voltage and current decimated samples available 200 us 2.5 kHz measurement bandwidth RMS and THD (optional) calculation of each voltage and current signal Selectable high pass filter for DC measurement Line period and phase shift measurement for each phase Phase voltage delays Full calibration (amplitude, power offset and samples offset for DC measurement) Two configurable LED for pulsed outputs Communication through USB in virtual com port mode with shell commands 6 kV galvanic isolation between the phases with 8 mm creepage and clearance Description Product status link The EVALSTPM-3PHISO evaluation board implements a complete three-phase EVALSTPM-3PHISO energy meter with low-cost shunt current sensors. The solution is based on the STPMS2 device, a double channel, 24-bits second order sigma-delta modulator, measuring voltage and current for each phase through a voltage divider and a shunt current sensor. Sensing circuitry and PCB layout are optimized to maximize signal-to-noise ratio for optimal accuracy. The STPMS2 oversamples the signal using a 4 MHz clock distributed in a synchronized way by the microcontroller and outputs voltage and current sigma-delta bitstreams, multiplexed on the same pin. The two-wire communication between STPMS2 modulator and MCU is isolated by STISO621W, 6 kV galvanic isolated interface, allowing up to 100 Mbps rate and low pulse distortion (<3ns) for safe and fast data transfer between isolated domains. The FW embedded in the solution exploits the DFSDM filters of the STM32F413RH to convert the six bitstreams into 24-bits voltage and current data, at 200 us rate. All the metrology parameters are computed real time on a 200 us basis. Two LEDs are available for active and reactive pulses generation. The FW also implements a virtual com port communication to easily access the internal parameters to read metrology data, to modify the internal configuration for a high flexibility of the application, and to calibrate the board. DB4332 - Rev 2 - March 2021 www.st.com For further information contact your local STMicroelectronics sales office. EVALSTPM-3PHISO Revision history Table 1. Document revision history Date Version Changes 04-Nov-2020 1 Initial release. 22-Mar-2021 2 Updated features list DB4332 - Rev 2 page 2/4