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<div class="headerdisplayname" style="display:inline;">Subject:
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Re: [TriEmbed] TriEmbed Digest, Vol 16, Issue 18 - Power
regulator questions</td>
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<div class="headerdisplayname" style="display:inline;">From:
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Shane Trent <a class="moz-txt-link-rfc2396E" href="mailto:shanedtrent@gmail.com"><shanedtrent@gmail.com></a></td>
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<div class="headerdisplayname" style="display:inline;">Date:
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09/19/2014 10:10 AM</td>
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<div class="headerdisplayname" style="display:inline;">To: </div>
Charles McClelland <a class="moz-txt-link-rfc2396E" href="mailto:chip@mcclellands.org"><chip@mcclellands.org></a></td>
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<div class="headerdisplayname" style="display:inline;">CC: </div>
Glen Smith <a class="moz-txt-link-rfc2396E" href="mailto:mrglenasmith@gmail.com"><mrglenasmith@gmail.com></a>, TriEmbed
Discussion <a class="moz-txt-link-rfc2396E" href="mailto:triembed@triembed.org"><triembed@triembed.org></a></td>
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<div dir="ltr">Cool work Chip. I look forward to reading more about
the project.
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<div>I wanted to pass along a trick that allows you to measure
your battery voltage in a standard Arduino setup without
requiring a voltage divider. In short, they use Vcc as the ADC
reference (as usual) but measure the 1.1V internal reference to
calibrate the ADC and then convert ADC counts to millivolts.
Just using the 1.1V reference on the ADC would require a voltage
divider to drop Vcc to less than the 1.1V ADC max limited by the
1.1V reference. I am using it with a Li-poly battery powered
project and seemed pretty accurate. There is extra code to get
the correct registers for several chips but it is pretty
straight forward.
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<div><a
href="http://provideyourown.com/2012/secret-arduino-voltmeter-measure-battery-voltage/">http://provideyourown.com/2012/secret-arduino-voltmeter-measure-battery-voltage/</a><br>
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<div>Shane</div>
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