Electronic Design

Designers Have Some Breathing Room, But California Power Deadlines Loom

Those of you scrambling to meet the July deadline for the California Energy Commission's power-supply efficiency standards have gotten a bit of a reprieve—though you're not getting as much of an extension as the Consumer Electronics Association thinks you need. After intense negotiations between the CEC and CEA last month, California pushed the deadline for its mandatory power-supply standards from this July to January 2007. In addition to a no-load ceiling of 500 mW, the California spec requires power supplies to meet active-mode efficiency goals measured at various test points.

While it's easy to rally round the green benefits of more efficient power supplies, the CEA objected to the mandates' do-or-die timing. The group argued that consumer electronics makers can't circumvent the processes required to get power supplies properly tested and certified.

Power-supply manufacturers may have been on notice that the standards were coming, but few wanted to design products based on draft standards, risking the possibility of multiple reworks. Manufacturers need time to build and test products for compliance. The CEA was petitioning for a full-year extension. The CEC agreed to six months.

"We have broad concerns, such as the use of outdated data, to justify California's regulations for consumer audio and video products, as well as concerns about how these regulations could undermine the broadly successful Energy Star program," said CEA president Gary Shapiro. "We also have specific issues with the Commission's regulations, including proposed effective dates, reporting requirements, and regulations for products that do not yet exist."

The CEC modified the mandate to exempt medical devices because the FDA requires an even lengthier testing and approval process. Further, the CEC agreed that devices could be tested at 115 V only, departing from the Energy Star international spec that requires testing at 115 and 230 V. Products tested and compliant at 115 V will be marked as such.

The technology to meet the CEC regulations is ready for design-in. Power Integrations' Tiny Switch-III offers 50-mW no-load power consumption, which is 10 times more efficient than the California requirement. The TinySwitch-III features a 700-V MOSFET alongside low-voltage control circuitry on a monolithic IC.

International Rectifier's SmartRectifier ICs for ac-dc power converters increase overall system efficiency by 1% while reducing MOSFET temperature 10°C. The IR1167 works independently from the primary control. It can operate in low-power "burst modes" to enable 1-W standby and comply with the CEC's 80Plus standard.

One of IR's targets for the SmartRectifier is TV power supplies. The rapid "supersizing" trend in this market could have a greater impact on national electric consumption than consumers (or designers) might realize.

According to a study prepared by Ecos Consulting for the Natural Resources Defense Council, higher-resolution televisions (particularly plasma TVs), can consume two to three times the power of similar-sized CRTs. And while per-set power consumption is growing, the number of TVs and the hours Americans spend in front of them also continue to rise.

By 2010, TVs will outnumber the population. Ecos estimates that U.S. TVs use over 46 billion kWh every year, or more than 1% of all U.S. electricity. The NRDC recommended last year that Energy Star specs be revised to compute average standby and active-mode power consumption, noting that the average household's TVs and associated electronics consume 1200 kWh per year (see the figure). That's more than10% of the average household's annual electricity bill (and more than Energy Star-rated appliances like refrigerators and washing machines).

With properly written specs, power-efficiency regulations can be a win/win/win for government, consumers, and the electronics industry. To make it work, specs have to make sense to power-supply designers, and deadlines need to give manufacturers the time to design-in the latest technologies.

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