Automatic servo address marking identification and timing compensation circuit for HDD

摘要

The hard disc drive has a servo synchronising signal detector 30 coupled to the servo address marking (SAM) signal detector 16. The output of the SAM detector is connected with a servo time compensation circuit 31. The SAM detector output error is identified 38 and used by a CPU 22 to provide an input to a SAM search mode control stage 40, coupled to the compensation circuit. A data sector end pulse generator provides an output to a stage that identifies the window of The SAM signal, and is fed back to control the SAM detector.