(3) Low voltage sensor
The low voltage sensor is equipped to protect the FDD from erroneous
operation due to the internal circuits construction of the FDD during
unstable state of the supplied voltage such as at power on or off.
The output of this sensor is ANDed to all the output drivers of the FDD.
Therefore, in the unstable state of +5V and +12V powfer when the internal
logic of the FDD does not function normally, it protects erroneous
operations of write driver and erase driver, erroneous signal output
to the host system, and etc.
+5V power
Low voltage
output
(U9,pin 17)
Power on
Power off
Note: Dotted line shows the LVS input pin 34 of U6 ,
control LSI.
___
(Fig.307)r Low voltage sensor waveforms
314
Содержание FD-55 Series
Страница 7: ...SECTION 3 THEORY OF OPERATION 300...
Страница 8: ...3 1 CONSTRUCTION AND FUNCTION 3 1 1 General Block Diagram Fig 301 General block diagram 301...
Страница 23: ...Fig 308 Control circuit block diagram 316...
Страница 40: ...SECTION 4 MAINTENANCE 4000...
Страница 56: ...J4 J12 Option J9 J5 Top view of the FDD Fig 401 Types of connectors 4016...
Страница 81: ...Collet shaft Front lever Gap between collet shaft and set arm hole Fig 412 Adjustment of set arm position 4043...
Страница 87: ...Fig 416 Adjustment of arm lifter Note Viewed from front bezel side Fig 417 Gap of arm lifter 4049...
Страница 95: ...Note Refer to item 4 2 1 as to handling of the set screw 4057...
Страница 97: ...j Repeat the procedure from item c to f Note Refer to item 4 2 1 as to handling of the set screw 4059...
Страница 102: ...k Key in Cl SET TMAX L Confirm as in item j 4064...
Страница 104: ...Notch B position TP6 voltage 0 5V Max LED indicator Fig 422 Check of file protect sensor 4066...
Страница 125: ...k Eject the level disk and release the Invert and ADD modes of the oscilloscope 4087...
Страница 136: ...Fig 431 Adjustment track alignment 4098...
Страница 153: ...Fig 436 Adjustment of index sensor 4115...
Страница 159: ...Head carriage Ass 1 Stepping motor capstan Guide shafts Fig 437 Replacement of head carriage Ass y 4121...
Страница 169: ...12 it is recommended to connect the FDD to the system for overall test Refer to item 4 2 5 1 4131...
Страница 172: ...Fig 440 Replacement of head pad 4134...
Страница 176: ...Plate Fig 441 CSS Ass y and shift lever position 4138...
Страница 177: ...SECTION 5 DRAWINGS PARTS LIST 500...
Страница 179: ...r Fig 501 External view No l 502...
Страница 181: ...PCBA DD motor servo Fig 503 External view No 3...
Страница 182: ...Fig 504 External view No 4 505...
Страница 183: ...Partis nrnnber of the FDD Fig 505 Extemal view No 5 506...
Страница 188: ...Fig 506 Mechanical section break down 511...
Страница 199: ...PCBA DD MOTOR SERVO PARTS LOCATION Type S i 522A...
Страница 200: ...PCBA DD TOR SERVO PARTS LOCATION Type TO 522B...
Страница 201: ...PCBA DD MOTOR SERVO PARTS LOCATION Type G 522C...
Страница 202: ...PCBA DD MOTOR SERVO PARTS LOCATION Type T 522D...
Страница 203: ...55 3 on I537Q2 5 or P S W Q U j k I J U C o fc I 3 W J V o 6 V y f t 523A PCPA DD MOTOR SERVO SCHEMATIC Type S...
Страница 204: ...523B PCBA DO MOTOR SERVO SCHEMATIC Type K...
Страница 205: ...o 523C i 1 PACB DD HOTOR SERVO SCHEMATIC Type G...
Страница 206: ...CV 5 3 3 H 2SV 523D PC DD M o t o r SERVO SCHEMATIC Type T...
Страница 207: ...PCBA MFD CONTROL B PARTS LOCATION PCB ISSUE A G 524A...
Страница 208: ......
Страница 209: ...PCBA FRONT OPT PARTS LOCATION 525 PO I...
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