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virtualdave
11-07-2012, 09:01 AM
Hi all,
Im curious what the difference is between the regular ground pin (GND) and the analog ground pin (AGND), and under what conditions would you use each? Any pointers?
Thanks,
David

t3andy
11-07-2012, 01:11 PM
Its a point of reference for measurement. The analog ground is used (reference) when reading the analogs and the digital ground
is used when using the digitals. I believe both grounds are tied together on the K20 chip but when using the high resolution analogs,
the analog ground should be only used with the analogs to cut down on the "noise" when reading analogs.

JBeale
11-07-2012, 05:55 PM
Apparently there is an inductor between AGND and GND. I see about 0.5 ohms of resistance between them, while the two GND pins are less than 0.1 ohm apart.

virtualdave
11-08-2012, 05:57 AM
Got it. Thank you both!

Paul
11-08-2012, 10:11 AM
Yes, AGND is meant for analog circuits.