インパルス性電磁雑音の自動測定に関する研究(IV) : 誘導雑音電磁界と回路の誤動作の関係

Experimental studies were made on electromagnetic susceptibility and malfunction of high speed CMOS digital printed circuit boards (PCB). We measured the induced noise voltage on a printed loop circuit caused by electromagnetic emission from an adjacent digital PCB. Electromagnetic susceptibility of a bus circuit was measured with a TEM cell in frequency range of 10 to 250 MHz. The induced noise increased near the resonance frequency of the circuit. We also measured the amplitude of noise voltage on a signal line that causes malfunction of a digital circuit, and the result shows that the marginal voltage depends on the supply voltage of CMOS circuit and the noise frequency