Cirrus Logic has a range of analogue front end (AFE) ICs for the design of single and polyphase utility meters.

The CS548X/9X family of metrology chips has a measurement accuracy of 0.1% over 4,000 dynamic range for both active and reactive energy.

A pre-programmed power calculation engine means there is no need for manual programming and also addresses security issues.

Calibration time is specified at two seconds.

Applications that incorporate features such as wireless and/or powerline communication, LCD displays, RTC or calendaring functionality, and digital IO are teh most likely applications for a design incorporating an AFE and microcontroller combination. 

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