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                          250837A 2.5" IDE DRIVE
     12.5 MM-High Hard Disk Drives with Integrated AT(R) Controller
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SPECIFICATIONS:

Configuration:

 Formatted Capacity, Mbytes: 
  251340 ................................... 1,340
  251005 ................................... 1,005
  250837 ................................... 837
 Integrated Controller: .................... AT 
 Encoding Method: .......................... RLL 1,7
 Buffer Size: .............................. 64K
 Disks: 
  251340 ................................... 4
  251005 ................................... 3
  250837 ................................... 3
 Data Surfaces: 
  251340 ................................... 8
  251005 ................................... 6
  250837 ................................... 5
 Tracks per Surface: ....................... 3,196
 Track Density: ............................ 5,080 tpi
 Recording Density: ........................ 92.2 kbpi
 Data Zones per Surface: ................... 16
 Bytes per Block: .......................... 512
 Sectors per Track: ........................ 66 to 132

 Physical:
  Height:  12.5mm
  Length:  100mm
  Width:   70mm
  Weight:  170g

Reliability and Maintenance:
  MTBF ..................................... 300,000 hours 
  Start/Stop Cycles......................... 50,000
  Component design life .................... 5 years (minimum)
  Data Errors (non-recoverable.............. <1 per 10^13 bits read

PERFORMANCE:

  Seek times (Typical):
      Track to track: ...................... 4.5ms
      Average: ............................. 14
  Average latency: ......................... 6.72ms
  Rotational Speed (+-0.20%):............... 4,464 rpm
  Controller overhead: ..................... <200uSec
  Data transfer rate:
      To/from Media: ....................... 6.0 Mbytes/sec
      To/from Host: ........................ PIO Mode 3,
                                             11.1Mbytes/Sec
      Start time (0 - Drive Ready): ........ 5 sec

 Power Requirements (Typical)

    Mode         +5VDC +5% -10%  Power +5.0VDC 
    ----         --------------  -------------
    Spin-up          1000mA         5000mW
    Idle              190mA          950mW
    Standby            50mA          250mW
    Sleep*              6mA           30mW
    * Total RMS

Environmental:

 Temperature (C)
    Operating .............................. 5C to 55C 
    Non-operating/Storage .................. -40C to 71C,
                                             (up to 10 days)
 Relative Humidity
 (Non-condensing)
    Operating, Non-operating/Storage ....... 5% to 95%
    Maximum wet bulb ....................... 26C

 Altitude 
 (relative to sea level)
    Operating .............................. -200 to 10,000 feet
    Non-operating .......................... Per MIL-STD-810E,
                                             Method 500.3
    
 Shock*     
    Operating Mechanical Shock ............. >100Gs
    Non-Operating Mechanical Shock 
      Critical Acceleration ................ 300Gs
    
 Vibration*
    Operating, random ...................... Per MIL-STD-810E,
                                             Method 514.4,
                                             10 min/axis

    Non-operating, random .................. Per MIL-STD-810E,
                                             Method 514.4, 
                                             10-500 Hz,
                                             60 min/axis

 Acoustic Noise (typical):
    Sound pressure ......................... 33dBA, idle


 * Without non-recoverable errors

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Interface Connector -
All these 2.5" drives have a 44 pin, combination interface/power 
connector. The four pins on the right, marked ABCD, are for "Master/Slave" 
or "Cable Select Option" selection.

Cable Select Option -
The drive can be configured so the status of a master or slave can be 
determined by the cabling from the host system. The drive can recognize 
itself as either Drive 0 or Drive 1.

The drive is configured as either a master (drive 0) or a slave (drive 1) 
depending on the value of the CSEL signal (pin 28). If CSEL is grounded, 
then the drive address = 0. If CSEL is open, then the drive address = 1. 
Special cabling is required from the system manfacturer to selectivly 
ground or open the CSEL signal. 


                            Back of Drive
    +============================================================+
    |       Pin 41:+5V                                           |
    |       v                                       1   C A      |
    +============================================================+
    | |   o o o o o o o o o o o o o o o o o o o o o o   o o   |  |
    | |   o o o o o o o o o o o o   o o o o o o o o o   o o   |  |
    +---=====================================================----+
            ^                     ^                     D B
            Pin 42:+5V            Pin 20 Key



                25XXXA JUMPER DESIGNATION      |D-B|A-B|C-D|
         +-------------------------------------+---+---+---+
         | Cable Select                        |   |   |   |
         |  Disabled*                          | O |   |   |
         |  Enabled                            | J |   |   |
         +-------------------------------------+---+---+---+
         | Master/Slave                        |   |   |   |
         |  Only drive in single drive system* |   | J | O |
         |  Master in dual drive system*       |   | J | O |
         |  Slave in dual drive system         |   | O | J |
         +-------------------------------------+---+---+---+
            J=Jumpered O=Open *=Default                      



                           CMOS Parameter Settings
              Model   Cylinders  Heads   WPC  LZ   Sectors
              --------------------------------------------
              250837    1621      16      0    0      63


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         251340, 251005, 250837 are trademarks of Maxtor Corporation
               AT is a registered trademark of IBM Corporation
               Specifications subject to change without notice
                      Copyright 1996 Maxtor Corporation
                        Rev 1.2    7/24/98    Lawley
                             
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