SanDisk® Corporation general policy does not recommend the use of its products in life support applications where in a
failure or malfunction of the product may directly threaten life or injury. Per SanDisk Terms and Conditions of Sale, the user
of SanDisk products in life support applications assumes all risk of such use and indemnifies SanDisk against all damages.
SanDisk FlashDrives are UL (Underwriters Laboratories) approved. They are for use only with UL approved computers or
systems. See this manual for FlashDrive installation instructions.
The information in this manual is subject to change without notice.
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Designed to replace traditional rotating disk
drives, SanDisk FlashDrives are embedded solidstate data storage systems for mobile computing
and the industrial work place. The 1.8-inch
FlashDrives (model SDIB) are compatible with
1.8-inch form factor hard disk drives. The 2.5- and
3.5-inch FlashDrives (models SD25B and SD35B)
are compatible with 2.5- and 3.5-inch form factor
disk drives. These FlashDrives, and all SanDisk
FlashDrives, feature an extremely light weight,
low profile form factor with 4 to 440 megabytes
(MB) of storage capacity.
SanDisk FlashDrives fit into standard disk drive
bays, use the industry standard IDE interface and
connect to the host system via the same ribbon
cable used to connect standard disk drives. No
additional device drives are required.
FlashDrives consist of an IDE compatible flash
memory controller and flash memory chip(s). See
Figure 1-1 for a system block diagram of these IDE
FlashDrive products.
This manual describes the key features and
specifications of SanDisk FlashDrives, plus the
information required by an engineer to interface
the FlashDrives to a host system.
1.2FlashDrive Product Models
FlashDrives are available in a variety of
capacities as shown in the following table. All
FlashDrives are shipped formatted with a DOS
• Supports automatic power management as
well as ATA power down commands and
sleep mode over the interface
• Automatic error correction and retry
capabilities
• Sophisticated defect management system
1.4Related Documentation
1.5.1Flash Technology Independence
The sector size of the FlashDrives is the same as
in a magnetic disk drive: 512 bytes. To write or
read a sector (or multiple sectors), the host
computer software simply issues a write or read
command. The command contains the number of
sectors to write/read and the address to
write/read. The host software then waits for the
command to complete. The host software does not
get involved in the details of how the flash
memory is erased, programmed or read. This is
extremely important as flash devices are expected
to get more and more complex in the future. The
intelligent IDE compatible interface used by the
FlashDrives will not need to change to support
new flash devices in the future and therefore the
host software will not need to change. Systems
that support the FlashDrives today will be able
to access future SanDisk IDE compatible products
built with new flash technology without having
to update or change host software.
American National Standard X3T9.2 AT
Attachment Interface Document
This document can be ordered from
Global Engineering Documents by calling
1-800-854-7179.
1.5Functional Description
The SanDisk FlashDrives contain a high level,
intelligent subsystem as shown in the block
diagram, Figure 1-1. This intelligent (microprocessor) subsystem provides many capabilities.
These capabilities include:
1. Standard ATA register and command set
(same as found on most magnetic disk
drives).
2. Host independence from details of erasing
and programming flash memory.
3. Sophisticated system for managing
defects (analogous to systems found in
magnetic disk drives).
4. Sophisticated system for error recovery
including a powerful error correction code
(ECC).
1.5.2Defect and Error Management
The FlashDrives contain a sophisticated defect
and error management system. This system is
analogous to the systems found in all magnetic
disk drives and in many cases offers enhancement.
For instance, disk drives do not typically perform
a read after write to confirm the data is written
correctly because of the performance penalty that
would be incurred. The FlashDrives do a read
after write under margin conditions to verify that
the data is written correctly (except in the case of
a Write without Erase command). In the rare case
that a bit is found to be defective the FlashDrives
can replace this bad bit with a spare bit. If
necessary the FlashDrives can even replace the
entire sector with a spare sector. This is
completely transparent to the host and does not
consume any user data space.
The FlashDrive specification for soft error rate is
much better than the magnetic disk drive
specification. In the extremely rare case that a
read error does occur, the FlashDrives have
innovative algorithms to recover the data. This is
similar to using retries on a disk drive but much
more sophisticated. The last line of defense is to
employ a powerful ECC to correct the data. If ECC
is used to recover data, defective bits are replaced
with spare bits to ensure they do not cause future
problems.
These defect and error management systems
coupled with the solid-state construction give the
FlashDrives unparalleled reliability.
1.5.3 Endurance
Even very heavy use of the FlashDrive in a
computer system will use only a fraction of the
total endurance over the computer’s five year
lifetime. For instance, it would take over 34 years
to wear out an area on the drive on which a file of
any size (from 512 bytes to drive capacity) was
rewritten 3 times per hour, 8 hours a day, 365 days
per year.
With typical applications (PIM software, word
processing, spreadsheets, data collection, etc.),
the 300,000 endurance limit is not of any practical
concern to the vast majority of users.
1.5.5Automatic Sleep Mode
A unique feature of the SanDisk FlashDrives is
automatic entrance and exit from sleep mode.
Upon completion of a command, the FlashDrives
will enter the sleep mode to conserve power if no
further commands are received within 5 msec. The
host does not have to take any action for this to
occur. In most systems the FlashDrives are in sleep
mode except when the host is accessing it; thus,
conserving power. Note that the delay from
command completion to entering sleep mode can be
adjusted.
When the host is ready to access the drive and it
is in sleep mode, any command issued to the drive
will cause it to exit sleep and respond. The host
does not have to follow the ATA protocol of
issuing a reset first. It may do this if desired, but
it is not needed. By not issuing the reset,
performance is improved through the reduction of
overhead but this must be done only for the
SanDisk products as other IDE products may not
have this feature.
1.5.4 Wear Leveling
The FlashDrives do not require or perform a Wear
Level operation. The command is supported as a
NOP operation to maintain backward
compatibility with existing software utilities.
1.5.6Power Supply Requirements
This is a dual voltage product which means it
will operate at a voltage range of 3.30 volts ± 5%
or 5.00 volts ± 10% (± 5% for industrial versions).
Note 1. All values quoted are typical at ambient temperature and nominal supply voltage unless otherwise stated.
Note 2. Sleep mode current is specified under the condition that all drive inputs are at static CMOS levels and in a
“Not Busy” operating state.
Note 3. The currents specified show the complete range of programmability in the FlashDrive memory drive. A
tradeoff between performance and maximum current used can be done using the Set Features command.
The FlashDrive defaults to the fastest speed and highest current. See the Set Features command for more
details.
Sleep:
Reading:
Writing:
Sleep:
Reading:
Writing:
3.3 V ± 5%5 V ± 10%3.3 V ± 5%5 V ± 5%
200 µA
(Slow - Fast)
32 mA - 45 mA
32 mA - 60 mA
150 mA/50µs
Standard 2.5" and 3.5"
FlashDrive
(Models SD25B and SD35B)
3.3 V ± 5%5 V ± 10%3.3 V ± 5%5 V ± 5%
200 µA
(Slow - Fast)
32 mA - 80 mA
32 mA - 80 mA
150 mA/50µs
500 µA
(Slow - Fast)
46 mA - 75 mA
46 mA - 90 mA
150 mA/50µs
500 µA
(Slow - Fast)
46 mA - 120 mA
46 mA - 120 mA
150 mA/50µs
Industrial 1.8" FlashDrive
(Model SDIBI)
200 µA
(Slow - Fast)
32 mA - 45 mA
32 mA - 60 mA
150 mA/50µs
Industrial 2.5" and 3.5"
FlashDrive
(Models SD25BI
and SD35BI)
200 µA
(Slow - Fast)
32 mA - 80 mA
32 mA - 80 mA
150 mA/50µs
500 µA
(Slow - Fast)
46 mA - 75 mA
46 mA - 90 mA
150 mA/50µs
500 µA
(Slow - Fast)
46 mA - 120 mA
46 mA - 120 mA
150 mA/50µs
2.3System Performance
All performance timings assume the FlashDrive
controller is in the default (i.e., fastest) mode at
Vcc = 5.0 volts.
Start Up Times
Sleep to write:
Sleep to read:
Reset to ready:
Active to Sleep Delay Programmable
Data Transfer Rate To/From Flash 4.0 MBytes/sec burst
Data Transfer Rate To/From Host 6.0 MBytes/sec burst
Controller Overhead Command to DRQ 1.25 msec maximum
Note:The Sleep to Write and Sleep to Read times are the times it takes the FlashDrive to exit sleep mode when
any command is issued by the host to when the drive is reading or writing. The FlashDrive does not require a
reset to exit sleep mode. See section 1.5.5.
Follow the procedure below to prepare for the
FlashDrive installation:
1. If replacing an existing hard disk drive,
make sure that all data on that drive has
been properly backed up.
2. Turn off the power to the host computer
system and unplug the power supply cord.
The host system’s power must be off during
the entire installation procedure.
3. Using a grounding strap, make sure that
you are properly grounded. You must be
grounded during the entire installation
procedure and when handling the
FlashDrive.
4. Remove the host computer system’s cover.
Caution: Be sure to check with the host
system’s user’s manual and the terms and
conditions of the system’s warranty before
removing the cover. Removing the cover of
a laptop computer may be difficult and
could void the system’s warranty.
5. If replacing the computer system’s existing
hard drive, remove the hard drive.
If the FlashDrive is being installed as a single
drive, go to section 3.3 to finish the installation
process. If the FlashDrive is being installed in a
two drive configuration, follow the steps in section
3.2 below to set the jumpers and then go to section
3.3 to finish the installation.
3.2.1Jumper Settings for 1.8- and 2.5-inch
FlashDrives
If the FlashDrive is being installed as the second,
or Slave drive, in a two drive configuration, pin B
or pin C must be grounded (see the Figures 3-1 and
3-2). Pins B and C are pulled-up input pins that
are shorted together internally (Pins A and D are
ground.) These pins are used to configure the
FlashDrive as a slave device. When either pin B
or pin C is grounded by the user, either using a
shunt jumper or through a ground on the host
motherboard if a 50 pin connector is used, the
FlashDrive is configured as a Slave device.
If both pins B and C remain open, the FlashDrive
is configured as a master in a master/slave
configuration or as the only drive in a single drive
system.
Master or Single Drive
AB
CD
Slave
AB
CD
Pin 1
Pin 1
3.2Installing the FlashDrive in a Two
Drive Configuration
If the FlashDrive is being installed in a system
that has either a hard disk or another
FlashDrive already installed, a jumper may need
to be installed for the FlashDrive(s) to operate
properly.
The jumper settings for the 3.5-inch FlashDrive
are shown on the FlashDrive’s label. The
master/slave configuration pins are the eight pins
between the four pin power connector and the 40
pin interface connector. The figure below shows
how the jumpers should be set for either master or
slave configuration on the 3.5-inch FlashDrive.
Figure 3-3
3.5-inch FlashDrive Configuration Pins
3.3Mounting the FlashDrive
Follow to the steps below to mount the
FlashDrive in your computer system:
four pin power connector must also be
connected on the 3.5-inch FlashDrive.
2. Mount the FlashDrive into the host
system. The FlashDrive can be mounted in
any orientation from the top, bottom or
side. The 1.8-inch FlashDrives use four
M1.6 screws in the corner mounting holes in
the PC board. The 2.5-inch FlashDrive
uses four M3 screws and the 3.5-inch
FlashDrive uses four 6-32 screws. See
Figures 2-1 through 2-5 and see the
Ordering Information section at the end of
this manual. Ensure that the cables are
not crimped or strained. Make sure that
all mounting screws are hand tightened
securely. For the 3.5-inch FlashDrive,
mounting screws must not extend more than
.25 inch into the frame. For the 2.5-inch
FlashDrive, mounting screws must not
extend more than 3 mm into the frame.
3. Perform the CMOS Setup. If the
computer’s BIOS has an auto-detect
function, use this option, otherwise,
determine if your system has a user
definable “hard drive types” selection in
the CMOS RAM. If your system has this
selection, continue with the CMOS setup.
If your system does not have this
selection, call SanDisk Applications
Engineering at (408) 542-0400.
Refer to the following table for
information required to set the user
definable “hard disk type” selection in
your system’s CMOS RAM to the
FlashDrive configuration. The table lists
the number of heads, sectors per track and
cylinders emulated by the FlashDrives.
After entering the appropriate
information, save the new CMOS setup by
rebooting your system.
1. Connect the FlashDrive to the host
system. If the host system’s cable
connector is not keyed, make sure that pin
1 from the host computer cable is connected
to pin 1 of the FlashDrive. Pin 1 on both
connectors has a square solder pad. If the
FlashDrive is being added to the system
as a slave drive, connect the daisychained connector to the FlashDrive. The