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Hi!
I was wondering whether is it possible to connect (VSSA and VDDA) to a different supply voltage other than that is being used for (VSSD and VDDD).
Also is it possible to connect VSSA to a slightly negative voltage, say -200mV as compared to VSSD which is referenced 0V for digital peripherals.
The configuration would look like:
VDDD = 3.3V
VSSD = 0V
VSSA = -0.2V
VDDA = 3.1V (VDDA-VSSA = 3.3V)
Thanks
Solved! Go to Solution.
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Won't work. Vdda must be the highest voltage for the chip.
Bob
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Well in that case how about this:
VDDD = 3.3V
VSSD = 0V
VSSA = -0.2V
VDDA = 4.8V (VDDA-VSSA = 5VV)
Are the VDDD and VDDA pins connected internally? (Same for VSSD and VSSA)
Also, if the requirement that VDDA must be >= VDDD is fullfilled, then is it OK to have VSSA biased to a slightly negative voltage?
This is to take care of saturation of analog peripherals and also to implement differential measurement for voltages that may swing to negative values.
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That is below the "Absolute Maximum Ratings". You'll need to test for yourself if it has the wanted effect or just a defect 😉
Bob