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Author Topic: DAC null voltage for (DAC1,0) ?  (Read 459 times)
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hello,
i'm running the following code on a due
....
void loop() {
 
analogWriteResolution(12);
   
analogWrite (DAC1,0); 
delay (10000);
analogWrite (DAC1,100) ;
delay (5000);
analogWrite (DAC1,0);
delay (5000);
analogWrite (DAC1, 200) ;
delay (5000);
analogWrite (DAC1,0);

etc.....

i can see the voltage steps on the scope but for analogWrite
(DAC1,0) i have 537mV an so on
DAC1,100 => 591
DAC1,200 => 645
DAC1,300 => 699
DAC1,400 => 753

i was expecting DAC1,0 to give me 0mV

any thought on what i'm doing wrong ?

cheers
Francois


PS: same problem on DAC0
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The dac got a voltage offset of 1/6 of 3.3v. The max voltage is 5/6 of 3.3v.
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i had same issue before. please check this.
http://forum.arduino.cc/index.php?topic=173747
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thanks for you help guys,

to sum up

from wibauxl
But on page 1059 of SAM3S datasheet, it is said that the voltage range of the DAC is from (1/6) x VADVREF to (5/6) x VADVREF.
So I suspect, the same applies to SAM3U, and range is 1/6 x 3.3V = 0.55V to 5/6 x 3.3V = 2.75V, which is verified by your measures.
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