The cure for Wall-Warts is here!

Xringer · 12-19-09, 07:38 AM

No-Load, Ultra-Low Standby and Remote-Off Mode | Power Integrations

Low standby current DC power supplies / battery chargers have been here for a while now.

I think we have a couple in our house now. But I would love to get rid of
those big (hot) transformer wall-warts ASAP..

I have a 9V wart from SparkFun that seems like it's a low load unit..
SparkFun Electronics - Wall Adapter Power Supply - 9VDC 650mA

Looks like this.. And is very light, compared to transformer types.

The IR pistol can't see much heat coming off it. It's got a red LED but seems
to be using very little power (when not plugged into a load).

Ryland · 12-19-09, 12:38 PM

looks like a switching power supply, those tend to show no draw with my kill-a-watt meter if they are not hooked to anything else, that is what my phone charger is, I would like to get one for my lap top (12v) and my mini projector (12v) I wonder what the payback on them is.

NiHaoMike · 12-19-09, 08:53 PM

Power supply circuits are one of the fields I'm going to be specializing in. One idea I have is what I call Period Skip Resonant (PSR), which is supposed to combine the high full load efficiency of a resonant power supply with the low standby losses of a PFM supply.

That said, the best way to reduce standby losses is to standardize on voltages and use one large power supply instead of many smaller ones.

12-19-09, 07:38 AM	#1
Xringer Lex Parsimoniae Join Date: Feb 2009 Location: Woburn, MA Posts: 4,918 Thanks: 114 Thanked 250 Times in 230 Posts	The cure for Wall-Warts is here! No-Load, Ultra-Low Standby and Remote-Off Mode \| Power Integrations Low standby current DC power supplies / battery chargers have been here for a while now. I think we have a couple in our house now. But I would love to get rid of those big (hot) transformer wall-warts ASAP.. I have a 9V wart from SparkFun that seems like it's a low load unit.. SparkFun Electronics - Wall Adapter Power Supply - 9VDC 650mA Looks like this.. And is very light, compared to transformer types. The IR pistol can't see much heat coming off it. It's got a red LED but seems to be using very little power (when not plugged into a load).

12-19-09, 08:53 PM	#3
NiHaoMike Supreme EcoRenovator Join Date: Oct 2008 Location: Austin, TX Posts: 1,154 Thanks: 14 Thanked 257 Times in 241 Posts	Power supply circuits are one of the fields I'm going to be specializing in. One idea I have is what I call Period Skip Resonant (PSR), which is supposed to combine the high full load efficiency of a resonant power supply with the low standby losses of a PFM supply. That said, the best way to reduce standby losses is to standardize on voltages and use one large power supply instead of many smaller ones. __________________ To my surprise, shortly after Naomi Wu gave me a bit of fame for making good use of solar power, Allie Moore got really jealous of her...

12-19-09, 12:38 PM	#2
Ryland Master EcoRenovator Join Date: Mar 2009 Location: Western Wisconsin. Posts: 913 Thanks: 127 Thanked 82 Times in 71 Posts	looks like a switching power supply, those tend to show no draw with my kill-a-watt meter if they are not hooked to anything else, that is what my phone charger is, I would like to get one for my lap top (12v) and my mini projector (12v) I wonder what the payback on them is.