Fujitsu MHY2060BH Manuel D’Utilisation

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Theory of Device Operation 
 
4-10 
C141-E262 
4.6  Read/write Circuit 
The read/write circuit consists of the read/write preamplifier (PreAMP), the write 
circuit, the read circuit, and the time base generator in the read channel (RDC) 
block which is integrated into LSI.  Figure 4.4 is a block diagram of the read/write 
circuit. 
4.6.1  Read/write preamplifier (PreAMP)  
PreAMP equips a read preamplifier and a write current switch, that sets the bias 
current to the MR device and the current in writing.  Each channel is connected to 
each data head, and PreAMP switches channel by serial I/O.  In the event of any 
abnormalities, including a head short-circuit or head open circuit, the write unsafe 
signal is generated so that abnormal write does not occur. 
4.6.2  Write circuit 
The write data is transferred from the hard disk controller (HDC) to the RDC in 
LSI.  The write data is sent to the PreAMP as differential signal from LSI, and the 
data is written onto the media. 
(1) Write precompensation 
Write precompensation compensates, during a write process, for write non-
linearity generated at reading.   
 
Figure 4.4  Read/write circuit block diagram