CDM peak current variations and impact upon CDM performance thresholds

Effect of device size on the peak CDM current is discussed. The current increases monotonically for small packages and then saturates for sizes larger than 1000 mm
²
. Size of the charge plate of the CDM tester contributed to this behavior. The current was not found to be constant across the package. Instead, it showed maximum value in the middle and minimum at the outer edge. An unexpected variation in CDM current is also reported for long pulse sequences.