The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 07, 2015
Filed:
Jun. 26, 2014
Hgst Netherlands B.v., Amsterdam, NL;
John Contreras, Palo Alto, CA (US);
Samir Y. Garzon, San Jose, CA (US);
Rehan Ahmed Zakai, San Ramon, CA (US);
HGST Netherlands B.V., Amsterdam, NL;
Abstract
A method, apparatus, and system are provided for implementing a power-on spin-torque oscillator (STO) oscillation checker to monitor STO resistance to identify STO oscillation with microwave assisted magnetic recording (MAMR) hard disk drives (HDDs). An amplitude modulated write coil drive current is applied to the write coil in the presence of a DC bias current applied to the STO. The amplitude modulated write coil drive current modulates the STO resistance monitored using an amplifier circuit to identify STO oscillation, used to ensure stable MAMR HDD write operation.