Implementing spin-torque oscillator sensing with enhanced delay control feedback circuit for hard disk drives

An apparatus for implementing data detection with spin-torque oscillator (STO) sensing for hard disk drives comprising:

• a spin-torque oscillator (STO) read sensor sensing a signal magnetic field and producing a readback signal;
• a delay line detector including
• a mixer receiving an input signal from said STO read sensor, said mixer coupled to an adjustable time delay for mixing said received input signal with a time delayed input signal and providing a detector output signal;
• a delay control feedback circuit monitoring a low frequency component signal of said detector output signal including a delay control function applying a delay control feedback signal to said adjustable time delay responsive to said monitored low frequency component signal to bias a level of said monitored low frequency component signal of said detector output signal;
• detector output signal being used for processing by data detection electronics.

A system for implementing data detection with spin-torque oscillator (STO) sensing for hard disk drives comprising:

• a media generating a magnetic signal having an amplitude determined by media field strength;
• a spin-torque oscillator (STO) read sensor sensing said magnetic signal generated by said media and producing a readback signal;
• a delay line detector including
• a mixer receiving an input signal from a STO read sensor, said mixer coupled to an adjustable time delay for mixing said received input signal with a time delayed input signal and providing a detector output signal;
• a delay control feedback circuit monitoring a low frequency component signal of said detector output signal including a delay control function applying a delay control feedback signal to said adjustable time delay responsive to said monitored low frequency component signal to bias a level of said monitored low frequency component signal of said detector output signal;
• detector output signal being used for processing by data detection electronics.