I am using MPC5606S Microcontroller.
I want to clear one concept and have a doubt.
The Microcontroller using 8MHz crystal on the pins 27 (XTAL) and 29 (EXTAL) And a 32.768kHz RTC crystal between pins 71 (XTAL32) and 72 (EXTAL32).
My understanding :
The Crystal is constantly bombarded with some noise composed of many frequencies. But since the Power is not provided to the microcontroller, the amplifier (OP-AMP amplifier) circuitry present inside the Controller is inactive and does not amplify the resonant frequency of the crystal which is 8MHz. Once, the Controller is powered, the amplifier is active and now only the 8MHz resonant frequency is amplified and is provided to the other sub-section blocks inside the microcontroller. Is my understanding correct?
My doubt :
What determines the voltage levels of the RTC 32.768kHz and 8MHz oscillations?
I have captured the below waveforms for both oscillations :