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8 years, 10 months ago.
AnalogIn on K64F board
I'm trying to use the analogin feature on this board and it seems like there is a strong pullup resistor internal to the uC being activated when the pin is designated as an analog input. This creates problems for me because my sensor has a finite output impedance so this is corrupting the measurement. For example: my sensor is driving out 0V but when its connected to the circuit board the voltage gets pulled up to about 1.6V.
It looks like pullups/downs can be controlled when the pin is designated as a digital pin, but that doesn't exist for when its in analog input mode.
Thanks for any help.