Research On Electromagnetic Damage And Protection Of Magnetic-resistance Head

The electromagnetic suppressing method in the thesis improved the product anti-interference ability, decreased the failure damage in the product line, reduced the loss caused by electromagnetic interference. At first, we apply SBD(Schottky Barrier Diode) to protect magnetic head basing on the ESD(Electro-Static Discharge) damage experiments, then the crosstalk noise of FPC(Flex Printed Circuit) is analysed and the measure of to change ground via layout is proposed to reduce the damage.The thesis includes the following parts:The simulator parameter has been evaluated by curve fitting between ESD waveform generated from simulator and simulation output.The HGA parasitic parameter's influence has been evaluated by ESD stress experiments, and give a explanation from the circuit view, realize the understanding of magnetic head stucture and damage mechanism.The SBD parameters has been extracted by I-V testing and simulation, then apply SBD to protect the HGA , to verify it by simulation.The crosstalk has been evaluated with the Pspice model of transmission line, and decrease the crosstalk from the view of changing the grouding via of transmission line.The main experiments are the ESD waveform capturing with oscillograph, electromagnetic interference for different discharge position such as between reader, between reader and ground and magnetic head surface, taking the SEM (Scanning Electron Microscope) and AFM (Atomic Force Microscope) photo of product, the SBD (Schottky Barrier Diode) I-V characteristic studying.In this thesis we obtain ESD simulator parameter, the magnetic-resistance head structure and SBD protection ability through experiment and simulation. The damage mechanism has been evaluated for ESD high-speed high-frequency electromagnetic interference which provide a theoretical basis for improving the structure of magnetic head and transmission line, and give a reference for reducing cost and raising anti-electromagnetic damage of HGA.