The AS8267 is a highly integrated CMOS single-phase energy metering device for fully electronic LCD meter systems. The AS8267 has been designed to ensure a meter’s full compliance with the international Standards IEC62052 and ANSI. The AS8267 includes all the functions required for conventional 1- or 2-current anti-tamper meters. The functions include precision energy measurement, an 8-bit microcontroller unit (MCU) with 32kBytes of Flash memory, an on-chip Liquid Crystal Display driver (LCDD), programmable multi- purpose Inputs/Outputs (MPIO), a real time clock/calendar (RTC) for complex tariff functions such as time-of-use or maximum demand billing and a Serial Peripheral Interface (SPI) for reading data from and writing data to an optional external non-volatile memory (EEPROM). The AS8267 has a dedicated energy measurement front-end, which includes an analog front-end and a programmable Digital Signal Processor (DSP) which provides active energy, mains voltage and mains current. Reactive and apparent energy can also be calculated.

The on-chip 8-bit 8051 compatible microcontroller is freely programmable and provides user access to the various functional blocks. The dedicated Universal Asynchronous Receiver / Transmitter (UART1) in the System Control block allows access to various system functions and blocks. A second UART (UART2) is also provided, which may for example be used for debugging. The on-chip memory includes 32kByte of highly reliable non-volatile Flash program (and data) memory and 1kByte of volatile data memory. The meter system designer also has the option of an additional external EEPROM memory, which is selectable in size from 1kByte to 32kByte (in binary steps).