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Author Topic: Can 5V be put into an analog pin with 1.1v ref. ?  (Read 285 times)
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I want to make a circuit for PWM control, i have a hand controller that will be controlling it and I think the easiest way to get good linearity is to put a larger resistor in series, the resistance of the controler is 0-60 ohms, with with a 1K resistor in series the resistance total would vary by 6% so would stay pretty linear, this would mean very poor resolution though so ideally I'd need to power the two from a higher voltage to get the voltage range up - or drop the measured range to match the outputted range. 1.1V ref with 5V supply is a good starter point. But it means that when the 0-60 resistor becomes disconnected which it does with the trigger at rest the ful 5V would go into the micro, will this be a problem with the micro powered from 5V ?
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No problem putting 5V into an analogue pin no matter what the referance, it will however read 1203 1023 like all voltages above the reference.
« Last Edit: June 23, 2013, 01:55:16 pm by Grumpy_Mike » Logged

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two digits swapped - 1023 (0x3FF)

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going off the scale is part of my plan  smiley-cool
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It is not off the scale it is the top of the scale.
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well 5V is off the scale for a 1.1Vref and will give 1023 by default so I'll take anything over 1000 as my mark
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