High Impedance - AT32UC3C0512

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HI
I am working with the DAC module. At the end of the work with the DAC I want to use this pin as high impedance (HIGH Z).It is possible? 
There is a option to work in High Z state with GPIO? 
THANK YOU VERY MUCH

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Yes, the High Z state is called "input".

 

Jim

Jim Wagner Oregon Research Electronics, Consulting Div. Tangent, OR, USA http://www.orelectronics.net

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Thank you about your answer. how do we know that?

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hello, 

 

When you say "this pin" do you mean the output of the DAC?  Yes you can change the data direction of the pin to make it an input.  When the internal pull-up resistor for this pin is disabled, the pin is high-impedance or "tri-state".  Which means that very little current is going to be flowing either into or out from this pin.

 

The only reason why that I can think of that this might be done is if there were two voltage sources, one is the DAC output and the other is a different voltage.  If the DAC were outputting +2 volts and the other input was connected to +5 volts, then enough current would flow from the +5v source to the +2 volt source to damage the DAC.  The output of the DAC has a limited amount of current that it can "sink".

 

But this is poor electronic design all around.  If you are going to combine or isolate low-level analog voltages, then use op-amp buffers.

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niroby wrote:

Thank you about your answer. how do we know that?

 

Because the datasheet says so.

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