Measuring the radiated emissions from a family of microprocessors using a 1-GHz TEM cell

This paper presents a series of measurements of the radiated emissions from 8 and 16 bit microprocessors. The radiated emissions were measured using a 1-GHz TEM cell that incorporates the device under test (DUT) into the cell structure itself. For the 16 bit processor, samples from each of the manufacturer´s identified process corners were measured and compared. Two separate fabrication lines were compared for process variability. The spatial location on the wafer was measured for emissions variation. In addition, emissions were measured for a 16 bit processor as a function of the operating temperature. Finally a comparison was made between discrete implementations of a module digital core and the same circuit implemented as an multichip module (MCM)