Effects of CW interferences on a 5 GHz monolithic VCO

The paper presented here is part of the electromagnetic susceptibility studies conducted on active circuits. An electromagnetic interference (EMI) is injected on an integrated voltage controlled oscillator (VCO). We describe the different effects observed on its operation mode when the circuit is subject to an EMI or high frequency signal. Three operating modes are observed. Some of them are confronted with Razavi's theory. Others highlight new phenomena in function of the aggression power.