Patent ID: 9672846
Date: 2017-06-06
CPC Classifications: G11B

Claim:
1. A magnetic recording apparatus comprising: a magnetic field-assisted magnetic recording (MAMR) head comprising a main pole, a spin torque oscillator (STO) positioned over the main pole, and write coils coupled to the main pole, and a controller operatively coupled to the MAMR head; wherein the STO is configured to generate a high frequency magnetic field on a magnetic medium, the controller is configured to supply the STO with first bias current at a first bias current level, the controller is configured to further supply the STO with second bias current at a second bias current level, and the controller is configured to time the second bias current to coincide with an electrical current overshoot in the write coils, wherein the second bias current comprises a second bias current ramp-up from the first bias current level to the second bias current level, a second bias current saturation at the second bias current level, and a second bias current ramp-down from the second bias current level to the first bias current level, and the electrical current overshoot comprises an overshoot ramp-up, an overshoot saturation, and an overshoot ramp-down.