An Engineer in Wonderland – 20mW stand-by, an expert replies

Several people responded to my ‘Full marks for 20mW stand-by’ blog about an excellent-looking power-saving device.

One of those was Mark Muegge, v-p of marketing at CamSemi, a company that I casually mentioned in the original.

He wrote:

Re: Engineer in Wonderland 20mW standby power article

We were excited to read about Energy Saving International’s new Savasocket ‘gadget’ to cut the ‘stand-by’ consumption of mobile phone chargers to 20mW because this has been our focus for quite some time.

Like your engineer, though, we are also left wondering about the source of the “100mW stringent self-imposed limit” comment.

While that source may be lost to history, the market is now gearing up to meet the demands of the new star rating scheme, where top specification five star-rated mobile phone chargers are required to have no-load power consumptions of less than 30mW.

This scheme was first announced in November 2008, as a part of an EU code of conduct initiative, by the world’s top five mobile phone brands: Nokia, Motorola, LG Electronics, Samsung and Sony-Ericsson.

And at the time, Nokia was estimating probably around 60% of the energy consumed by a mobile phone charger was during no-load mode.

Two years ago cutting no-load power to just 10% of the Energy Star 2.0 limit of 300mW was seen as a tall order. Even worse was that the mobile phone makers expected this aggressive reduction to be achieved without impacting cost or any other performance specification.

In our experience the market is fully signing up for five star designs, not only for higher end products but as the new standard for the volume market. Within the next year we would expect <30mW to become the norm: as it is, we can already deliver 20mW with a charger start-up time of less than 0.3s so the charger instantly responds when a handset is reconnected.

But meantime, until the chargers make it to market and we upgrade our mobiles, Savasocket seems like a great solution.

Yours sincerely

Mark Muegge

VP Marketing CamSemi


 – who could easily have dreamt the 100mW figure.

If you so wish, respond below.

No email addresses are collected for marketing purposes from responses to this blog. I will keep it that way for as long as possible.

Leave a Reply

Your email address will not be published. Required fields are marked *