Hi,
Attached schematics Pierce oscillator implemented in micro-controller(according data sheet). We captured wave on XTAL_IN and XTAL_out pins.
XTAL_OUT - 25Mhz clock running on bias VDD/2;
XTAL_IN - 25Mhx clock running on bias 0;
Both doesn't contradict with theory.
However one thing I don't understand: AND component using as amplifier supplied by Vdd(generally this is micro controller power source). How it managed to amplify input signal with zero bias?
May be power invertor implemented inside or another technique for providing negative power rail for this component? Or in some way was implemented bias VDD/2?
Thank you