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Barracuda 18LP

Average Seek Time:

18.21 GB
7200 rpm
6.9 ms

Installation Guide | Product Manual


Odd characters? Click here for help. A version of this specification with the linedraw characters approximated by text is available by clicking here.

                         SEAGATE TECHNOLOGY, INC.
                            (C)opyright 1998

ST-318275LW Ultra2 SCSI Wide (Barracuda 18LP, LVD)

   REAR VIEW   (ST-318275LW only)
        (TOP)                  J5 Auxiliary
          ___________________  敖  1/様様様様\
        ( 忻忻忻忻忻忻忻忻1)由::::::崖 0 0 0 0 突
          \陳陳陳陳陳陳劃陳/    陳 2拈5GG12
       68 pin I/O Cable        崖崖崖
       Connection Male          崖崖崖   SCSI ID = 0 (none)
                                崖崖垣陳 SCSI ID = 1
                   pin-11 +5v 陳抒崖青陳 SCSI ID = 2
                   pin-10 GND 陳潰垣陳陳 SCSI ID = 4
                                  団陳陳 SCSI ID = 8
      pins 9 & 12 no connection   青陳陳 or pin-8 Activity LED*

* These pins are driven low for 250ms after PWR ON and RESET
  to allow jumper selectable SCSI ID as shown above.

   REAR VIEW   (ST-318275LC only)
                     80 pin I/O and DC Power Wall/bracket Connection
    J1          /陳陳劃陳陳陳陳陳陳陳\      TOP (HDA)
     様様様様様/ 忻忻忻忻忻忻忻忻忻忻 \様様様様様
              (\1陳陳陳陳陳陳陳陳陳40/)    BOTTOM

     Notes on 80 pin I/O connector:
       pins  1 -  4 = +12v        41 - 44 = 12v GND
            34 - 36 = +5v         74 - 76 = 5v GND
                 37 = SYNC             77 = LEDC
                 38 = MTRON            78 = DLYDST
                 39 = SCSIA0           79 = SCSIA1
                 40 = SCSIA2           80 = SCSIA3

  Mating connector: AMP US p/n: 2-557103-1 straight-in, Male 80-pin
                                   2-557101-1 right angle to PCB

   SIDE VIEW   (ST-318275LW/LC)

             FRONT    TOP (HDA)    J2  87654321              嬪
              OF 様様様様様様様様様様様様様様様様PWA様様様J1
             DRIVE    BOTTOM           ::::::::              塒
 Force Single-ended (LVD models only) 潰崖崖崖 Term Power (LW only)
           Start Delay (12 secs * ID) 陳抒崖垣 Reserved            
                          Motor Start 陳潰崖青 Reserved            
                        Write Protect 陳陳拈陳 Parity Disable      
                     Termination Power-source Table 団陳陳陳陳陳陳潰
                                   ....様様PWA edge様様 
                                                2 1       
                     A Drive Supplies Bus        崢      
                      (not used on LC model)    囗      
                    青陳陳陳陳Default no jumper 陳陳陳陳陳潰

     Note: LW and LC drives do not have internal terminators or
           any other way of adding internal terminators to the
           drive; use external active termination if required.
           Use active (ANSI SCSI-2 Alternative 2) terminators
           when terminating the bus.  Use active negation
           terminators when terminating a SCSI Ultra2 bus
           operating in Low Voltage Differential (LVD) mode.

   FRONT VIEW   (ST-318275LW/LC)
                                  敖調Reserved. Shipped with cover installed.
                                    Do not remove. Do not install jumpers
                      TOP (HDA)  孩様邑     1
                 *    BOTTOM     塒様余123456
                                J6    崖崖崖
            LED 潰                     崖崖崖
                            Remote LED 抒崖垣 ID 1
                           (pin-11 +5v) 崖垣 ID 2
                              Reserved 潰垣陳 ID 4
                           (pin-10 GND)  青陳 ID 8


       UNFORMATTED CAPACITY (GB) ________________
       FORMATTED CAPACITY (GB) __________________18.21
       AVERAGE SECTORS PER TRACK ________________303 rounded down
       ACTUATOR TYPE ____________________________ROTARY VOICE COIL
       TRACKS ___________________________________117,210
       CYLINDERS ________________________________11,721 user
       HEADS ______PHYSICAL______________________10
       DISCS (3.5 in) ___________________________5
       MEDIA TYPE _______________________________THIN FILM/MR
       RECORDING METHOD _________________________PRML 16/17 EPR4
       INTERNAL TRANSFER RATE (mbits/sec)________137 to 240
       EXTERNAL TRANSFER RATE (mbyte/sec) _______40 Sync
            Low Voltage Differential(LVD) _______80 Sync
       SPINDLE SPEED (RPM) ______________________7,200
       AVERAGE LATENCY (mSEC) ___________________4.17
       BUFFER (/optional)________________________1024/4096 KByte
         Read Look-Ahead, Adaptive,
         Multi-Segmented Cache
       INTERFACE ________________________________Ultra2 SCSI
              ASA II, SCAM level 2 (1 default)
       BYTES PER TRACK __________________________186 KByte avg
       SECTORS PER DRIVE ________________________35,566,480
       TPI (TRACKS PER INCH) ____________________12,580
       BPI (PEAK KBITS PER INCH) ________________223
       AVERAGE ACCESS (ms read/write)____________6.9/7.7
         Drive level without controller overhead
       SINGLE TRACK SEEK (ms read/write) ________0.9/1.2
       MAX FULL SEEK (ms read/write) ____________15/16
       MTBF (power-on hours) ____________________1,000,000
       SHOCK (G's, 11/2 ms):
                operating (Read/Write) __________5
                abnormal ________________________10
                nonoperating ____________________75/150
       ACOUSTICS (Bels typical, sound power) ____4.1
       POWER DISSIPATION (watts/BTUs) Active ____16.8/57.3
                                      Idle ______9.75/33.3
       POWER REQUIREMENTS: +12V START-UP (amps) _1.6
                           +12V TYPICAL (amps) __0.5 idle
                           +5V START-UP (amps) __1.05
                           +5V TYPICAL (amps) ___0.75 idle
                           IDLE (watts) _________
       LANDING ZONE (cyl) _______________________AUTO PARK
       IBM AT DRIVE TYPE ________________________0 or NONE

                        Height (inches/mm):      1.0/25.4
                        Width  (inches/mm):     4.00/101.6
                        Depth  (inches/mm):     5.75/146
                        Weight    (lbs/kg):      1.3/0.589

Already low-level formatted at the factory with x spare sectors at
the end of each x cylinder region.  

ZBR = Zone Bit Recording = Variable sectors per track

Seagate reserves the right to change, without notice, product 
offerings or specifications. (11/13/99)

A copy of this specification file may be obtained by FTP at