| 摘要 |
Spin-torque oscillator (STO) power on, for microwave assisted magnetic recording on (MAMR) hard disk drives (HDDs), is detected based on noise. A low frequency noise generated by a spin torque oscillator, such as noise in a frequency range 10 kHz and 100 MHz, is detected. The detected STO noise is compared to a predefined threshold to identify STO oscillation. The oscillation can be detected with static or pulsed positive and negative write current. The noise detector may have an adjustable frequency range. STO oscillation detection is used to ensure stable write conditions. STO degradation can also be detected and the threshold and STO bias can be re-optimized allowing continued operation of the hard disc drive. |
