Date: 04/10/2012

ADI introduces isolated metrology chipset for energy metering apps

Analog Devices, Inc., (ADI) has introduced a fully isolated metrology chipset designed for polyphase energy metering applications. The ADE7978 metrology chipset consists of the ADE7978 3-phase metrology IC combined with up to four ADE7933 fully isolated A/D converter ICs. The ADE7933 3-channel sigma-delta A/D converter incorporates ADI’s patented iCoupler and isoPower technologies to implement isolated signal transfer and dc-to-dc power conversion across a 5kV-rated insulation barrier. This allows the use of shunt resistor sensing elements instead of current transformers (CTs), thereby offering immunity to magnetic field interference and tampering.

"Designers of 3-phase electric meters are increasingly adopting shunt-based architectures over traditional CT-based meters to take advantage of size, cost, and magnetic immunity benefits,” said Ronn Kliger, director, Energy Group, Analog Devices. “This new full-featured metrology chipset allows them to quickly leverage these benefits without compromising functionality or performance."

Features:
1. Computes active, reactive, and apparent energies for class 0.5 meters (ADE7978)
2. Offers full power quality measurements including THD (ADE7978)
3. Two versions of A/D converter IC available: three channel (ADE7933) and two channel (ADE7932)
4. Integrated isoPower isolated dc-to-dc converter (ADE7933/ADE7932): Enables real time compensation for shunt temperature drift using on-chip temperature sensors (ADE7978 and ADE7933/ADE7932)
5. Flexible SPI, I2C, and HSDC serial interfaces (ADE7978)

Product Sample availability Channels Price each in 1,000 quantities Packaging
ADE7978 3-phase metrology IC Now N/A $1.90 28-pin LFCSP
ADE7933 3-channel isolated ADC Now 1 current channel and 2 voltage channels $5.71 20-lead wide body SOIC with greater than 8mm clearance and creepage
ADE7932 2-channel isolated ADC Now 1 current channel and 1 voltage channel $5.42 20-lead wide body SOIC with greater than 8mm clearance and creepage

The EVAL-ADE7978EBZ evaluation board for the ADE7978 chipset is now available at a price of $350.00.

For more information: http://www.analog.com/ADE7978

Source: Analog Devices