An investigation of ESD protection for magnetoresistive heads

Many precautions are taken to avoid damaging electrostatic discharge (ESD) through disk drive magnetic recording heads featuring readback via a magnetoresistive (MR) sensor. By optimizing protective spark-gaps (PSG) in the recording head, the extent of ESD damage can be reduced. Human Body Model (HBM), Machine Model (MM) and Charged Device Model (CDM) transients are applied to simulated soft-adjacent-layer (SAL)-biased MR heads with and without protective spark-gaps. Design principles for ESD-damage-suppressing spark-gaps in MR heads are developed and several implementations compared.