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Topic: Trying to understand DAC limitations of a Due (Read 212 times) previous topic - next topic

chryssalid

I'm trying to model some simple electric/electronic circuits using DAC pins as power sources.
Something like this, but with different voltage and resistance values.


I want to know how much current a DAC pin can draw (in case when current flows from one source to another due to voltage difference between them). Is it possible to model something like this without a risk of frying Due?

Another problem is, I am going to output sine waves from DACs, and so there will be capacitors in my circuit to remove DC offset from each DAC, and the circuit I am modelling consists almost entirely of inductors. Should I put some sort of circuit protection in my scheme in case negative current flows back to one of the DAC pins?




Zapro


Grumpy_Mike

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want to know how much current a DAC pin can draw

Do you mean source or sink?
It is very small and you will find the answer in the data sheet for the processor or on ant of the Due graphic pin out diagrams like the one in the sticky post at the start of this section.

chryssalid

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School-assignment?

No, university project. I am redesigning an old huge laboratory complex which was basically an analog computer for electric power system modelling. I want either to replace some of its components or design a much smaller laboratory stand using microcontrollers. My question is related to the latter approach: I am trying to build the same laboratory stand in my home to try out some ideas I have.

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Do you mean source or sink?


Actually, sort of both.
Although I am using both DACs as sources, the DAC with lower voltage output will function as sink, because current will flow into it. If I rephrase my original question, I want to know if DAC can operate as sink.

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It is very small and you will find the answer in the data sheet for the processor or on ant of the Due graphic pin out diagrams like the one in the sticky post at the start of this section.


Thanks for suggestion.
As I see from the pinout diagram, it's a low current pin; its limits are 3mA (source) and 6mA (sink). I'll do circuit analysis for my analog model to see whether that's enough or not.

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or on ant of the Due graphic pin out diagrams

I am sorry for the silly question, but what is an "ant" in that context?

Grumpy_Mike

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I am sorry for the silly question, but what is an "ant" in that context?

In this context ant is my iPad trying to correct my spelling of "any".

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