Application of a Miniature Parallel Strip Line to Hard Disk Drive Immunity Test

A parallel strip line of very small size has been designed and fabricated in order to study the susceptibility of hard disk drive heads to electromagnetic noise. The target voltage standing wave ratio and internal-to-external field ratio have been confirmed up to at least 6 GHz. Calibration was conducted by measuring the field across the termination resistors. One example of susceptibility test to hard disk drive is shown.