Markos, It is very simple I have done this many times in my days job, use a resistive divider and work out the error by calibrating the input and fix any error in software. One thing you have to be careful of is that you monitor the temperature as well as many resistors vary their resistance with temperature, but it depends on your application if you are charging lead acid batteries then you may only have to calibrate the circuit between the usable voltage range of interest.
Have a look at http://www.angelfire.com/electronic/hayles/charge1fig3.html note the divide by 4 voltage sense connecting to the ADC input of the PIC micro-controller. Regards, Rod Markos wrote: > Hi guys, > maybe this is a little offtopic, but i'm sure you could > help me. I'm implementing a simple battery charger, and I need to > messaure voltages ranges from 0 to 12 V. > ¿Could I use the PIC integrated ADC to messaure above 5 V (provided that > I use the voltage reference pins tied to 0 and 12 V, for example)? Most > external ADC have a 0 to 5V input range.... > How would you guys solve this? Any Ideas? > > Thanks in advance. > > > ------------------------------------------------------------------------- > Take Surveys. Earn Cash. Influence the Future of IT > Join SourceForge.net's Techsay panel and you'll get the chance to share your > opinions on IT & business topics through brief surveys-and earn cash > http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV > _______________________________________________ > Sdcc-user mailing list > Sdcc-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/sdcc-user > > ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ Sdcc-user mailing list Sdcc-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/sdcc-user
