ADE7754多相多功能带串口的电能计量芯片

　　The ADE7754 is a high accuracy polyphase electrical energy measurement IC with a serial interface and a pulse output. The ADE7754 incorporates second order Σ-∆ ADCs， reference circuitry， temperature sensor， and all the signal processing required to perform active， apparent energy measurements， and rms calculation. The ADE7754 provides different solutions for measuring active and apparent energy from the six analog inputs， thus enabling the use of the ADE7754 in various power meter services such as 3-phase/4-wire， 3-phase/3-wire， and 4-wire delta. In addition to rms calculation， active and apparent power information， the ADE7754 provides system calibration features for each phase （i.e.， channel offset correction， phase calibration， and gain calibration）。 The CF logic output provides instantaneous active power information. The ADE7754 has a waveform sample register that enables access to ADC outputs. The part also incorporates a detection circuit for short duration low or high voltage variations. The voltage threshold levels and the duration （number of half line cycles） of the variation are user programmable. A zero-crossing detection is synchronized with the zero-crossing point of the line voltage of each of the three phases. The information collected is used to measure each line’s period. It is also used internally to the chip in the line active energy and line apparent energy accumulation modes. This permits faster and more accurate calibration of the power calculations. This signal is also useful for synchronization of relay switching. Data is read from the ADE7754 via the SPI serial interface. The interrupt request output （IRQ） is an open-drain， active low logic output. The IRQ output goes active low when one or more interrupt events have occurred in the ADE7754. A status register indicates the nature of the interrupt. The ADE7754 is available in a 24-lead SOIC package.