## Re: [Gumstix-users] Monitoring battery voltage from lipo's

 Re: [Gumstix-users] Monitoring battery voltage from lipo's From: Alex Gibson - 2010-08-19 23:13:54 ``` Easiest would be something like an arduino and talk to overo via rs232. Arduino (simplified c/java cross for avr's) is very easy to use sparkfun sells a lot http://www.sparkfun.com/commerce/categories.php?c=103 See their tutorials and the arduino tutorials http://www.sparkfun.com/commerce/tutorials.php http://www.sparkfun.com/commerce/tutorial_info.php?tutorials_id=195 http://www.arduino.cc/en/Tutorial/HomePage You could just use one of the onboard adc's via a resistor netowrk to drop the maxium battery output voltage to a level suitable for the adc to read. If the batteries max voltage is 25V The adc's max input voltage is 2.5V Then you need a resistor network that divides the voltage by 10. http://en.wikipedia.org/wiki/Voltage_divider If my heads working correctly this morning if you pick R1 = 1k R2 = R1 / ((Vin/Vout) - 1) R2 should be approx 112ohms to give a max output of 2.5V Try this http://www.raltron.com/cust/tools/voltage_divider.asp On 20/08/2010 8:32 AM, Alex Gibson wrote: > On 20/08/2010 5:58 AM, vwyodapink wrote: >> ero running from my lipos. What I would like to know >> how to do or if its even possible. Would I be able to use a pin on summit to >> monitor the battery voltage coming from my lipos balancing plug? So that way >> I could monitor the voltage on each cell from the pack. Also if this is >> possible, can I monitor multiple lipo's in the same manner from their >> balance port? I tried doing some searching but not even sure what or where >> to look for this one. The voltages of my batteries are below. > > I2C or spi adcs ? > > or use the onbard adc's via resistor network > > May make more sense to use a small micro (avr , pic or arm7/arm cortex > M) to do the monitoring > then send the data via rs232 or spi/i2c or via can(can to usb - usb on > overo end) > > Alex > > -- > UTS CRICOS Provider Code: 00099F > DISCLAIMER: This email message and any accompanying attachments may contain > confidential information. If you are not the intended recipient, do not > read, use, disseminate, distribute or copy this message or attachments. If > you have received this message in error, please notify the sender > immediately and delete this message. Any views expressed in this message > are those of the individual sender, except where the sender expressly, and > with authority, states them to be the views the University of Technology, > Sydney. Before opening any attachments, please check them for viruses and > defects. > > ------------------------------------------------------------------------------ > This SF.net email is sponsored by > > Make an app they can't live without > Enter the BlackBerry Developer Challenge > http://p.sf.net/sfu/RIM-dev2dev > _______________________________________________ > gumstix-users mailing list > gumstix-users@... > https://lists.sourceforge.net/lists/listinfo/gumstix-users -- UTS CRICOS Provider Code: 00099F DISCLAIMER: This email message and any accompanying attachments may contain confidential information. If you are not the intended recipient, do not read, use, disseminate, distribute or copy this message or attachments. If you have received this message in error, please notify the sender immediately and delete this message. Any views expressed in this message are those of the individual sender, except where the sender expressly, and with authority, states them to be the views the University of Technology, Sydney. Before opening any attachments, please check them for viruses and defects. ```