Radiated electromagnetic immunity analysis of VCO using IC stripline method

As system integration in wireless portable electronic devices has increased significantly, the analysis of electromagnetic compatibility (EMC) has become important to prevent the malfunction of integrated circuits (ICs). To evaluate the radiative immunity of an integrated circuit, we employ the IEC-standardized IC stripline method. In this paper, we provide an electromagnetic immunity analysis of the radiated electromagnetic noise coupling from an IC stripline to a ring voltage-controlled oscillator (VCO). We present the design of an IC stripline that meets the IEC 62132-8 standard, the test setup and the experimental results of the VCO test chip. The measurement shows that the radio frequency (RF) source from the IC stripline causes changes in the center frequency and output characteristics. VCO output variations show that the design is relatively immune to radiated noise of the same frequency as the oscillator output, and the output frequency spectrum spreads out more with higher noise amplitude due to injection. The experiment shows that the IC stripline method is an effective solution for the radiated electromagnetic analysis of an IC.