The STPM32, STPM33 and STPM34 ICs help utilities ensure consistent billing from customer utility meters. The STPM3x devices prevent errors below 50 mA in energy meters and prevent up to MW-hours of lost billings across a large customer base. The ICs help keep meter accuracy to a few mA, comparable. By performing power-quality calculations on-chip, including rms voltage and current measurement, apparent-energy computation, and under-voltage, over-voltage detection, the chips can offload the meter’s host processor thus simplifying software.
Neutral-phase tamper detection in the STPM33 and STPM34 helps simplify the design and enhance system security. The STPM34 can also calculate apparent power in single- and multi-phase systems. The STPM3x devices integrate key functions including a voltage regulator, a temperature-compensated voltage reference supporting long-term accuracy, and a SPI/UART host connection to simplify hardware design and save external components and PCB size. The ICs measure frequencies down to dc, while their wide bandwidth allows accurate measurement of harmonic content for power-quality assessment. They are compliant with applicable IEC and ANSI standards.
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