                         SEAGATE TECHNOLOGY, INC.
       Customer Technical Support FAX Network +1 408 438-8137
     Customer Technical Support Bulletin Boards (300-9600, 8-N-1)
Ŀ
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                            (C)opyright 1993



ST-3390N
Rear View               50 pin SCSI Interface I/O connector
                       
                                           DC power
   (TOP)        ͸ /5GG12\
          ͵::::::::::::::::::::::::1͵ 0 0 0 0 
   (BOTTOM)   ; 
                 1 1 1
                   
                  Terminating Resistor Packs


ST-3390N
Left View                       o o o1
              (TOP)             o o o     ͸
     Front....͵ I/O connector
                                       ;
             SCSI Address ID 1   
                          ID 2  
                          ID 4 


ST-3390N
Right View

                 o o4     o o o6         (TOP)
           ͸  1oo     1oo o
    DC Power       
           ;            
                        
                        Active/Passive Termination
                    
     Terminator Power  Ŀ
                   Active: Pins 1 & 2 shorted     
                               only (+2.85V to        
                               110 ) for FAST        
                               SCSI;                  
                      Passive: Pins 2 & 4 shorted     
                               AND pins 5 & 6 shorted 
                               (+5V and GND to        
                               220/330 ) for         
                               standard SCSI.         
                      
                  
    Ŀ
    Terminator Power: From SCSI Connector  Pins 1 & 2     
                      From Power Connector  Pins 1 & 3     
                      To SCSI Connector Only  Pins 3 & 4     
                      From Power Connector and  Pins 1 & 2 AND 
                        to SCSI Bus --------------------------- 3 & 4     
                     Terminating Resistors not Installed  Pins 2 & 4     
    


ST-3390N
Front View

                  SCSI ID's (none for ID0)
                                     not used if ID set on side jumpers
                     Ext. Spindle Clock Synch
                                    pin-5 is Clock Ground
                      Remote LED
  (TOP)        Ŀ        Reserved
               4 2 1   Ŀ
               o o o o o-o o o o o
              1o o o o o+o o o o o  o o o o+
               1o o o o-
                                       
  (BOTTOM)                              Remote LED
                                       Ext. Spindle Clock Synch
                                             pin-5 is Clock Ground
                                      Remote Start Enable
                                     Parity Enable


                             ST-3390N


       UNFORMATTED CAPACITY _____________________
       FORMATTED CAPACITY (xx SECTORS) __________344.3
       AVERAGE SECTORS PER TRACK ________________83 rounded down
       ACTUATOR TYPE ____________________________ROTARY VOICE COIL
       TRACKS ___________________________________8,028
       CYLINDERS ________________________________2,676 (user)
       HEADS ____________________________________3
       DISCS (3.5 in) ___________________________2
       MEDIA TYPE _______________________________THIN FILM
       HEAD TYPE ________________________________THIN FILM
       RECORDING METHOD _________________________ZBR RLL (1,7)
       INTERNAL TRANSFER RATE (mbits/sec) _______21.6 to 36.3
       EXTERNAL TRANSFER RATE (mbyte/sec) _______4 Async
       EXTERNAL TRANSFER RATE (mbyte/sec) _______10 Sync
       SPINDLE SPEED (RPM) ______________________4,500
       AVERAGE LATENCY (mSEC) ___________________6.67
       BUFFER ___________________________________256 Kbyte SeaCache
        Multisegmented, read look-ahead
       INTERFACE ________________________________SCSI-2 Fast
       BYTES PER TRACK __________________________42,888 avg.
       SECTORS PER DRIVE ________________________672,480
       TPI (TRACKS PER INCH) ____________________3,000
       BPI (BITS PER INCH) ______________________52,602
       AVERAGE ACCESS (ms) ______________________12
       SINGLE TRACK SEEK (ms) ___________________<4
       MAX FULL SEEK (ms) _______________________30
       MTBF (power-on hours) Office _____________250,000
       POWER REQUIREMENTS: +12V START-UP (amps) _1.9
       POWER MANAGEMENT (Watts):
                           ACTIVE _______________5.75
                           IDLE _________________3.0
       WRITE PRECOMP (cyl) ______________________N/A
       REDUCED WRITE CURRENT (cyl) ______________N/A
       LANDING ZONE (cyl) _______________________AUTO
       IBM AT DRIVE TYPE ________________________0

Formatted at the factory with 2 alternate cylinders.  Total physical
cylinders equal 2678.

       Physical:
                        Height (inches/mm):     1.00/25.4
                        Width  (inches/mm):     4.02/102.1
                        Depth  (inches/mm):     5.77/146.6
                        Weight    (lbs/kg):     1.5/0.68

Note: If FAST SCSI transfer rates are used, then the active
termination options must be used.  If the transfer rates are 5.0
MBytes/sec and below, either method of termination can be used.
Although active and passive terminated devices can be installed on the
same bus, both ends of the cable should be terminated in the same
manner, either both active or both passive.

Note: If your application requires no terminators, remove the
terminators from the circuit board.  Merely removing the terminator
power source selection jumper does not disconnect the terminator
resistors from the circuit.

ZBR = Zone Bit Recording = Variable sectors per track

Seagate reserves the right to change, without notice, product
offerings or specifications. (08/08/94)

