Shop our Airplanes Products Shop our Surface Products
Thread Tools
Old Sep 21, 2008, 11:32 AM
duhh is offline
Find More Posts by duhh
Registered User
Joined Dec 2005
47 Posts
current limitting with just one adc input ??

can this be done ?? Idea`s are welcome ..

The problem is, I have the vref- and vref+ already set and I dont them to get to close to each other as I use adc for controlling the amount of power to the motor and I dont want that conversion to be to sensitive. Also as te titel did allreay mention. I have only one analog or digital input/output pin left
on my pic16F88.

I`m thinkking about using the piece of cable from the battery to the negative connection of the controller as the shunt. So I only need one measuring point as the other point would just be the ground. but I`m concerned about precision.

Well thinking about it, I just need to calculate.. vref- is ground 0 and vref+ is 5 Volt so 5 Volt : 255 = 0,01960784313725490196078431372549 volt precision
lets say I want about 10 amp acurracy than 0,01960784313725490196078431372549 x 10 = 0,1960784313725490196078431372549 Ohms of cabe resistance is what i need ... and it would than be capable of measuring up to 255 x 10 = 2550 Amp. I have no idea if this is possisible .. and also connectors and stuff needs to be the same resistance everytime its reconnected ..

Anny way, anny thoughts, idea`s or experiences are well apreciated.

measuring voltage only at one point.
duhh is offline Find More Posts by duhh
Reply With Quote
Sign up now
to remove ads between posts
Old Sep 21, 2008, 11:39 AM
Comatose is offline
Find More Posts by Comatose
Dimension Engineering
Akron, Ohio
Joined Jan 2002
1,705 Posts
Current sense amp. I like max4173. Easy as pie.
Comatose is offline Find More Posts by Comatose
Reply With Quote

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Airliner--where can I place with just one Duct Fan? jascamera Electric Ducted Fan Jet Talk 8 Feb 17, 2007 01:32 PM
Coming to terms with letting one go.. Andy W Electric Plane Talk 47 May 07, 2003 10:16 PM
Can I use just one type of connector??? Roger_One Power Systems 33 Mar 26, 2002 04:32 PM
Mini IFO first flight , just one silly question though... Jeremy_D Parkflyers 8 Jun 01, 2001 06:23 PM
Just one of those days... Sal C Electric Plane Talk 5 May 13, 2001 10:18 PM