Disk Drive Operation
WA31273A / WA32543A / WA33203A / WA32163A / WA31083A / WA32162A5-11
5-2-2 Read/Write IC
The Read/Write IC, shown in figure 5-4, provides read/write processing functions for the drive. The
Read/Write IC receives the RD GATE and WR GATE signals, write data, and servo AGC and gates
from the Interface Controller. the Read/Write IC sends decoded read data and the read reference clock.
It receives write data from the Interface Controller.
When it is connected to the output of the head amplifier it performs the signal conditioning, data
qualification, data synchronization and encoding/decoding task with a minimum of external
components. There are 5 major functional modules in the Read/Write IC:
•
Automatic Gain Control (AGC)
•
Filter/Equalizer
•
Pulse Qualifier
•
Data Separator
•
Servo Demodulator
These modules are described in the following sections and shown in figure 5-2-2
.
5-2-2-1 Automatic Gain Control (AGC)
The Automatic Gain Control (AGC) is used to maintain a constant signal amplitude at the input of the
pulse detector while the input to the amplifier varies.
