HDD-level electrostatic discharge (ESD) failure voltage of tunneling magnetoresisive (TMR) heads

HDD-level electrostatic discharge (ESD) failure voltage of drives equipped with TMR heads and flying height control heaters is measured. An ESD gun is used up to 30 kV to simulate ESD events on the base plate of HDD. In this study, ESD sensitivity of two different types of HDD (Type A and Type B) was studied. The test results showed that the average failure voltage of Type A drive (12 kV) is lower than Type B (21 kV) even though HSA-level ESD failure voltages are similar. Disk, disk damper, write-to-read crosstalk, and location of ground via in suspenson interconnect play important roles in ESD sensitivity of the TMR head.