AC power metering gets personal with new system-on-chip

You may be familiar with the Kill-a-Watt power meter. It plugs into an ac outlet and allows you to measure the Watts or VAC used by appliances powered from that outlet. It  pretty much dominates the personal power meter market at this time, and costs about $20.

Today, Teridian Semiconductor, which previously has played only in the big utility-level power meter IC market, announced its 78M6612 power and energy measurement chip for home and enterprise use. The chip is for a single-phase AC power and includes a 32-bit compute engine, an MPU core, real-time clock and flash memory. It offers a 22-bit delta-sigma ADC, 4 analog inputs, digital temperature compensation, and a precision voltage reference to support a wide range of single phase, dual outlet power measurement application with darn few external components. At a minimum, it requires only a power supply, a couple of resistors and switches, a crystal oscillator and a current transformer to implement power metering.

If you’ve peeked inside a Kill-a-Watt (or looked at the documentation for a Tweet-a-Watt) you’ve seen the number of components that the 6612 replaces.

Each 6612 can monitor up to two ac outlets, but look for its widespread use to be its  integration into appliances, and most likely computers and servers. Data farms appear to be moving to individual monitoring of racks or even individual servers, and a power meter SOC plays nicely in that market. (Also look for several other IC vendors to introduce similar products in the near future.)

The 6612, comes in 64 pin LQFP and 68 pin QFN packages and costs $2.89 ea. in sample quantities of 100.