HP 7936 Support Manual page 110

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·
DISC
,..
DATA BUS ·
~
l
DATA PATH
CONTROL BUS
PHERAL
""
SERVO
~RF
ACE
CONTROL BUS •
f 00/
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STANDARD
DISC DATA BUS
CHANNEL "-
INTERFACE
ADDRESS/
(ESI)
DIAGNOSTIC
·
DATA PATH CONTROL BUS
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SWI~CHES
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SERVO CONTROL BUS
"-
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PCA-A1
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(
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SERVO
PLL AND
C~NTROLLER
SERVO
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TIMING
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SERVO
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SERVO
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POWER
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POSITION
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ERROR
SWITCH
DEDICATED
SERVO
POSITION
CKT
ERROR
ACTUATOR DRIVE
~
..
L._
-.~
- - - - -
~·AD/WR·I
TE PCA-A2
.,
HEAD
r
SELECT
ENCODER
HEAD
ADDRESS
READ/
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DATA WRITE
WRITE
(VLFM) CHAIN
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CONTROLLER
READ CLOCK,
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PLL &
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DATA
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READ
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CHAIN
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SEPARATOR
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SAMPLED SERVO
..
SAMPLED
-
SERVO AGC
~
·
AGC
AMPLIFIER
HEAD GAIN REF
·
DEDICATED SERVO
DEDICATED
SERVO AGC
AGC
..
AMPLIFIER
-
L._
_.-.J
r
r
~
~
Functional Description
7936 and 7937
r - - - - - - - - - - - - - - - - - - - - - - - ,
I HEAD/DISC ASSY A3
I
I
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I
I
I
I
I
•
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HEAD
GAIN REF
HEAD GAIN
HEAD
REFERENCE
ADDRESS
PROM & DAC
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-
HEAD
~
SELECT
READ
READ/WRITE
PREAMP/
WRITE
DATA (VLFM)
AND SERVO
DRIVER ICs
CODE
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--
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ACTUATOR
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-
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-
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SERVO
HEAD
S DATA AND EMBEDDED
SERVO CODE
DEDICATED
SERVO SURFACE
SERVO CODE
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READ PREAMP/
WRITE
AIR
FILTRATION
SYSTEM
I
DRIVER
I
IC
I
L _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ .J
PULLEYS AND
DRIVE BELT
.----'~---,
- - -
-
L - _ - - ' _ _ _ _
DC
AC
BRAKE
SPINDLE
I
MOTOR
I
FAN
__ ~
Figure 5-16. Disc Drive Basic Block Diagram
5-79