Understanding Noise in Oscillators — Lesson 2

This lesson covers the concept of noise in oscillators, specifically in CMOS RF integrated circuits. It delves into the architecture of oscillators, the role of inductors and capacitors in determining the frequency of operation, and the impact of process variations and temperature variations on these components. The lesson also discusses the concept of voltage-controlled oscillators and how they can be tuned to achieve a desired frequency. It further explains the role of phase noise in oscillators, how it can be calculated, and its impact on the performance of the oscillator. For instance, the lesson uses the example of a radio to illustrate how tuning can adjust the frequency of the oscillation to match the desired radio station.

Video Highlights

08:07 - How a PN junction diode can be used in oscillators
19:41 - Noise in an oscillator and how it can be analyzed
28:20 - Noise current source
43:13 - What happens at resonant frequency?
54:10 - Phase noise in an oscillator and why the small signal analysis method

Key Takeaways

- Voltage-controlled oscillators can be tuned to achieve a desired frequency.
- Noise in oscillators can be calculated and has a significant impact on the performance of the oscillator.
- The frequency of operation is decided by the resonance frequency between the inductor and the capacitor.
- Voltage-controlled oscillators can be tuned to cover a large range of frequencies.
- Phase noise can impact the performance of the oscillator.