READ/WRITE CHANNEL CIRCUIT AND HARD DISK DRIVE HAVING THE SAME

摘要

A read/write channel circuit and an HDD(Hard Disk Drive) with the circuit are provided to enable a variable gain amplifier to perform amplification operation based on a detected servo address mark, thereby removing a saturation phenomenon of the amplifier occurring from a DC(Direct Current) section. A servo gate signal outputted from a micro controller is received(S10). A read/write channel circuit responds to a servo gate signal to receive ammonite servo patterns having plural servo address marks and plural preambles outputted from a preamplifier, and detects the first and second servo address marks from the received servo address marks(S20). A variable gain amplifier of the read/write channel circuit is enabled on the basis of the detected first servo address mark, and is disabled on the basis of the detected second servo address mark(S30).