Single-phase, anti-tamper LCD energy-metering IC offers secure programme and data with high reliability

The AS8268 from austriamicrosystems delivers a single-chip solution for single-phase energy metering, with system-on-chip integration including 32 kbytes of Flash memory to support secure programme and data storage.

All required functional blocks for single-phase metering are included, allowing a complete meter implementation using a minimum of external components. A programmable energy-indicator pulse can be output to an LED through one of the GPIOs. Two UARTs provide for external communication. The IC also fulfils all utility anti-tamper requirements.

Active energy, mains voltage and mains current are calculated directly within the on-chip DSP. Reactive power and apparent power can also be calculated with user-configurable application software. A low-power battery operating mode allows meter reading when mains voltage is not present. The AS8268’s precision output, combined with an on-chip pulse counter, also enables fast, automatic digital calibration. The on-chip Real-Time Clock/Calendar (RTC) is accurate to ±1.4ppm, with two alarm registers and battery back-up available for complex-tariff applications.

An integrated temperature sensor enables added precision. There is also the option of using an external EEPROM from 2 kbytes to 32 kbytes for data retention, in conjunction with the on-chip Flash.

Delivered in a 64-pin LQFP package, the enhanced device is pin-compatible with the currently-available AS8218 and AS8228.

The AS8268 includes a precision energy-measurement front-end, an 8-bit 8051-compatible MCU, the on-chip Flash memory, a real-time clock, 96-segment LCD driver, 12 programmable GPIOs and an on-chip temperature sensor.

 

FEATURES On-chip voltage reference Power supply monitor 5mA operating current (depending on CPU activity) Low-power 3.0MHz to 4.0MHz crystal oscillator Programmable MCU clock Operating temperature range: -40ºC to 125ºC

APPLICATIONS Single-phase metering One-current or two-current meters with anti-tamper General energy-measurement applications

 

 

austriamicrosystems / AS8268