09 Aug 2005 | Geneva

STMicroelectronics Announces Reference Platform for Simplifying 'Smart' Electric Power Metering

Geneva / 09 Aug 2005

Geneva, August 9, 2005 – STMicroelectronics (NYSE: STM), one of the world’s leading broad line semiconductor suppliers, has introduced a reference design platform for the emerging market for electronic power meters. Electronic energy meters are replacing traditional electromechanical meters in many residential, commercial and industrial applications because the versatility and low-cost afforded by electronic meter designs allows meter manufacturers to implement many features that were impractical with the older mechanical designs.

For example, an electronic design can protect against meter tampering and theft of service. It also can measure and record energy usage at different times of the day, so utilities can bill customers for energy based on time of usage. An electronic energy meter also can enable automatic meter reading (AMR), whereby energy metering data is transmitted to the utility over a power-line communications link. Furthermore, electronic meters pave the way for ‘sub-metering’ of smaller operating units (for example, metering each apartment rather than just the building).

By drawing on its portfolio of dedicated and standard products and working closely with industry leaders in the power-metering field, ST has developed a design platform that can be rapidly and economically adapted to meet all low and medium end requirements.

The reference platform provides a modular solution that can be adapted by software to meet the utility company’s particular needs. It comprises two printed circuit boards, one dedicated to the mains power measurement functions and one implementing sophisticated computational and supervisory functions. The measurement board supports all current measurement technologies, from the most accurate Rogowski coils to inexpensive shunt resistors. It can monitor both Live and Neutral current for tamper detection and complies with all international standards such as IEC- 62052-11 and IEC – 62053-2x for metering equipment (AC).

The measurement board is based on the ST device, the STPM01 power metering chip, which includes all necessary signal conditioning, signal processing, data conversion, input/output signals and voltage reference. The STPM01 can be used as a stand-alone device in 1-phase kWh meters or as a peripheral in microprocessor-based 1-phase or 3-phase energy meters, in which case active (base and wide), reactive and apparent energy, VRMS, IRMS, instantaneous voltage and current, and line frequency readings are available through the SPI bus.

The Control Board is based on an ST7 microcontroller and is supplied with a library of C-code software, with many additional software routines available free of charge from the ST website. The ST7 microcontroller communicates with the STMP01 ASSP via the industry standard SPI interface protocol, allowing easy customization of metering functions via the included PC software. The reference design also includes the M41ST87 real-time clock chip, a 256-kbit serial SPI bus EEPROM and a dedicated 32-character alphanumeric LCD with on-glass driver.

For both boards, PCB schematics, BOM and Gerber files are available.

Notes for Editors

* Improved accuracy and lower power consumption are key benefits of electronic metering. With a mechanical meter, the error in the basic energy usage measurement is of the order of 1% but with an electronic implementation it is possible to reduce that error to less than 1%. Moreover, running the mechanical meter, with its continuously spinning dial, may require hundreds of milliamps. That power consumption can be reduced to a couple milliamps in an electronic energy meter, producing big power savings for the utility.

* Electronic meter designs also change the economics of manufacturing energy meters. A single hardware design may be customized for different customers and markets through changes in software. In addition, calibrating the finished meter at the factory is much easier with an electronic meter design.

* Another consideration is the demand for mechanical-meter replacements that are as inexpensive as possible. In parts of the developing world where many new customers are being connected to the grid, the low cost of the electronic meter is its main attraction.

About STMicroelectronics
STMicroelectronics is a global leader in developing and delivering semiconductor solutions across the spectrum of microelectronics applications. An unrivalled combination of silicon and system expertise, manufacturing strength, Intellectual Property (IP) portfolio and strategic partners positions the Company at the forefront of System-on-Chip (SoC) technology and its products play a key role in enabling today's convergence markets. The Company's shares are traded on the New York Stock Exchange, on Euronext Paris and on the Milan Stock Exchange. In 2004, the Company's net revenues were $8.76 billion and net earnings were $601 million.

Latest from ST