A Potential Matching Circuit for the Arm Electronic Preamplifier
Original Publication Date: 2001-Dec-25
Included in the Prior Art Database: 2003-Jun-20
The invention is to add a potential matching circuitry and its output to an Arm electronic AE) module. This invention is to be used in conjunction with a magnetic read/write system (e.g. a Hard Disk Drive) in which the potential matching output can be utilized. The magnetic read/write system will consist of the AE, the TSA or any conduit between the AE and the transducer, the transducer itself, and the usual rotating components of a HDD. A specific example of a transducer is the shielded Giant Magnetoresistive (GMR) heads. As the magnetic spacing between the head and the rotating media continues to decrease and as the read gap continues to decrease to support higher linear densities, the threat of a catastrophic transducer failure increases. One of the failure modes can be attributed to Electrostatic Discharge (ESD) events. The ESD event need not be in the MR sensor itself but rather between and among the sensor leads, the shields and the media. The discharging events occur because of potential differences in the transducer that promote charge build up. For timing and/or recovery performance considerations, the potential differences can not always be eliminated. Therefore, by adding a potential matching voltage from the AE the potential differences between the sensing transducer and its shields can be minimized without having to compromise HDD performance.