Synthesis based introduction to opamps and phase locked loops

The opamp and the phase locked loop can be synthesized from the prototype negative feedback system which uses an integrator to continuously drive the output until the error between the desired and actual outputs becomes zero. Different opamp topologies are shown to be logical outcomes of synthesizing such a system and progressively improving its performance. The phase locked loop is synthesized as a frequency multiplier, analogous to a voltage amplifier. The synthetic approach from a common foundation helps students to easily make connections between different negative feedback circuits.