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Silicon Labs current sensor chips

2008-11-17 21:13:03.633506+00 by Dan Lyke 3 comments

Silicon Labs makes current sensor chips which do the integration and temperature calibration automagically, including a $19.95 current sensing evaluation kit that takes up to 10A in and gives 2.0v out. I think I want to figure out how to build something with the 20A chip, but couple this with an AVR RAVEN and even at off-the-shelf and lots of capability that'll never get used this is close to "put one on every socket in the house".

[ related topics: Cool Technology Real Estate ]

comments in ascending chronological order (reverse):

#Comment Re: made: 2008-11-17 22:07:00.515171+00 by: Dan Lyke

So if you've gotten this far ("Hi, Dad!"), anyone got suggestions for building a safe device that deals with 15A loads on a PCB? How big should the traces be? Are there considerations about solder temperature that I should worry about?

Also, how about extremely low current power supplies to run the microcontroller with? When I was thinking about doing this with a current transformer, I was thinking I could charge NiCads or a supercap with a parasitic load off of a similar arrangement, but this says that I want something simpler. I guess it's time to dig out that switching power supplies tome I've got somewhere, see what sort of drain various capacitors have, and see if I can build a nano-watt scale power supply. Of course doing that right also means that I have to manage the CPU power fairly effectively.

#Comment Re: made: 2008-11-18 00:52:22.388234+00 by: Larry Burton

Dan, pick up a copy of Ugly's Electrical Pocket Reference Book to help you answer these questions.

#Comment Re: made: 2008-11-18 01:15:37.731728+00 by: meuon

The Standard is 5a current sensor, and you buy CT's aka Current Transformers for higher currents. I just got in 9 CT's. 3 of them are 2500:5 factor, that means 2500 AMP capacity, at 480 volts.. x 3 phases, one for each phase.

And Larry, Thanks for the link to Ugly's book. I'm buying at least one. :)