Preamplifier circuit with magnetoresistive sensor ESD protection
US6259573A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 22, 1999 |
| Grant date | Jul 10, 2001 |
| Priority date | — |
| Expiry date | Feb 22, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K1/18
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A preamplifier circuit to improve the ESD immunity of magnetic recording devices having magnetoresistive (MR) sensors, without degrading the sensor's high-frequency characteristics. The preamplifier circuit is coupled to an MR sensor having one terminal grounded. The preamplifier circuit includes a varistor coupled between a power supply line and a ground terminal. If a high voltage, exceeding the varistor voltage, is applied to the chassis (ground), it is discharged through the varistor between the power supply voltage line and the ground terminal, instead of through the MR head or the arm electronics module. The present invention thereby protects the MR head and the arm electronics module from ESD damage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.