Chapter 6. Hard Disk - Sharp PC-4741 Service Manual

(b) CN2 pin configuration
t2iR-hlo.....-
Q; Svmbnl
(j)
+B supply +B
<2l
N.C
®
GND. GND.
(c) CN3 pin configuration
Pin No. Signal name
Symbol
(j) Intensity control VR VR
<2l
GND. GND.
@ Control CaNT
5-4-3. Circuil diagram
>j-"-----!--1,-0' ... ' ,,---,"
Fig. 5-4
CHAPTER 6. HARD DISK
CP4024 (20MB)
SPECIFICATION SUMMARY
CAPACITY 21.8 Mbytes Formatted
PHYSICAL CONFIGURATION
Head Type
Disk Type
Actuator Type
Number of Disks
Data Surfaces
Data Heads
Servo
Tracks per Surface
Track Density
Track Capacity Formatted
Bytes per Block
Blocks per Drive
Sectors per Track
PERFORMANCE
Composite
Plated Thin Film
Rotary Voice-Coil
1
2
2
Embedded
627
1150TPI
17,408 Bytes
512
42,636
35 physical; 34 user
Seek Times%. Track to Track: 8 ms
Average: 29 ms:t:::+c
Maximum: 50 ms
Average Latency 10.3 ms
Rotation Speed (± .1 %) 2913 RPM
Controller Overhead 1 ml?
Data Transfer Rate (To/From Media) 1.125
Data Transfer Rate (To/From Buffer) 3.375
-27-
Start Time (Power
Up)~n
(0-3575 RPM)
(0 RPM - READY)
Stop Time (Power Down)
Start/stop cycles
Interleave
:t::
At nominal D.C. input voltages.
-
P C-4741
typical: 5 seconds maximum: 10
secollds
typical: 7 seconds
maximum: 15 seconds
typical: 5 seconds
maximum:
10
seconds
20,000 min.
1 :1
:t::t:: Average seek time is determined by dividing the total time
required to seek between all possible ordered pairs of track
addresses, by the total number of these ordered pairs.
~~* These numbers assume spin recovery is not invoked. If spin
recovery is invoked, the max could be 40 sec. Briefly removing
power can lead to spin recovery being invoked.
CP4024
READ/WRITE
Interface
Recording Method
Recording Density (I D)
Flux Density (ID)
POWER REQUIREMENTS
Task File
2 of 7 RLL code
23.148 bits per inch
15,432 flux reversals per inch
TYPICAL MAX
+5VDC
POWER
+5VDC
POWER
±10%
±10%
RiWMODE 750ma 3.8 W .789 ma 3.9 w
SEEKING MODI' 500 ma 2.5 W .52 ma 2.59W
IDLE MODE 300 ma 1.5 W .388 ma 1.94W
STANDBY MODE
130 ma
0.65W .188 ma
.94W
SLEEP MODE
70 ma
0.4 W .120 ma .60W
SPIN-UP MODE 1.25 amp 6.25W 1.45 amp 7.25W
NOTES: 1) READiWRITE mode occurs when data is being read
from or written to the disk.
2) SEEKING MODE occurs while the actuator is in motion.
3) IDLE MODE occurs when the drive is not reading, writ~
ing or seeking. The motor is up to speed and DRIVE
READY condition exists. Actuator is residing on last ac~
cessed track.
4) STANDBY MODE occurs when the motor is stopped,
actuator parked and all electroniGs except interface
con~
trol is in sleep state. STANDBY MODE will occur after a
programmable timeout since last host access occurs.
Drive ready and seek complete status exist. The drive
will leave STANDBY MODE upon receipt of a command
which requires disk access or upon receipt of a spin up
command.
5) SLEEP MODE occurs when the host issues the SLEEP
command to the drive. SLEEP MODE is the same as
STANDBY MODE except that interface control is also
powered down. To exit the SLEEP MODE, the Host
Reset line on the interface must be asserted. The SRST
bit in the Digital Output Register is useful for this
pur~
pose.
6) Maximum noise allowed (DC to 1 MHZ, with equivalent
resistive load): +5V DC: 2%.
7) SPIN UP MODE current draw is for 5 seconds max.