--0__=8ilo8fasuTVt46XJIsAQvmvSaVpnRn2LpFufyMxUUpDRZ27FRWoJTZEl Content-type: text/plain; charset=us-ascii Content-Disposition: inline Hall effect sensors can also be used in this application to detect the flux lines radiating from the motor supply leads. Don't know a part number off the top of my head, but a quick search on the web should turn up some hits. Scott F. Touchton 1550 Engineering Manager JDS Uniphase |--------+-----------------------> | | Vasile | | | Surducan | | | | | | | | | 04/05/01 | | | 03:28 AM | | | Please | | | respond to | | | pic | | | microcontroll| | | er discussion| | | list | | | | |--------+-----------------------> >----------------------------------------------------------------------------| | | | To: PICLIST@MITVMA.MIT.EDU | | cc: (bcc: Scott Touchton/US/UNIPHASE) | | Subject: Re: [OT]:Current Sensor | >----------------------------------------------------------------------------| Use a small resistor and a curent to voltage converter. example: 0.1 ohm , 25mV to 250mV drop-out, convert this potential with a good operational amplifier to 0-5V Vasile On Thu, 5 Apr 2001, Thomas N wrote: > Hi everyone, > > I am building a robot and I want to monitor the current drawn by the motor. > The motor can draw from 250mA up to 2.5Amp! What do I have to do to measure > this current? > > I was thinking of puting a 1-ohm resistor probe in series with the motor, > and feed the voltage drop across the resistor into a ADC, but at 2.5A, the > voltage drops across the resistor is too high and it leaves nothing for the > motor! > > Is there any current sensor circuit out there that have very low loading > resistance? Is there any IC doing this job? > > Thanks > > Thomas > _________________________________________________________________________ > Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com. > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. > > -- http://www.piclist.com#nomail Going offline? 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