CY7C68300B/CY7C68301B
CY7C68320/CY7C68321
Figure 16-3. X-ray Image of the Assembly
ensure that devices have large enough buffers to handle the
flow of data to/from the drive. The exact buffer size needed
depends on a number of variables, but a good rule of thumb is:
17.0
Other Design Considerations
Certain design considerations must be followed to ensure
proper operation of the CY7C68300B/CY7C68301B. The
following items should be taken into account when designing
a USB device with the CY7C68300B/CY7C68301B.
(aprox min buffer) = (data rate) * (seek time + rotation time + other)
where other may include things like time to switch heads,
power-up a laser, etc. Devices with buffers that are too small
to handle the extra data may perform considerably slower than
expected.
17.1
Proper Power-up Sequence
Power must be applied to the CY7C68300B/CY7C68301B
before, or at the same time as the ATA/ATAPI device. If power
is supplied to the drive first, the CY7C68300B/CY7C68301B
will start up in an undefined state. Designs that utilize separate
power supplies for the CY7C68300B/CY7C68301B and the
ATA/ATAPI device are not recommended.
18.0
Disclaimers, Trademarks, and Copy-
rights
Purchase of I2C components from Cypress or one of its sub-
licensed Associated Companies conveys a license under the
Philips I2C Patent Rights to use these components in an I2C
system provided that the system conforms to the I2C Standard
Specification as defined by Philips. Microsoft and Windows are
registered trademarks of Microsoft Corporation. Apple and
Mac OS are registered trademarks of Apple Computer, Inc.
EZ-USB AT2LP, EZ-USB AT2, EZ-USB FX2 and EZ-USB TX2
are trademarks, and EZ-USB is a registered trademark of
Cypress Semiconductor Corporation. All product and
company names mentioned in this document are the trade-
marks of their respective holders.
17.2
IDE Removable Media Devices
The CY7C68300B/CY7C68301B does not fully support IDE
removable media devices. Changes in media state are not
reported to the operating system so users will be unable to
eject/reinsert media properly. This may result in lost or
corrupted data.
17.3
Devices With Small Buffers
The size of the ATA/ATAPI device’s buffer can greatly affect
the overall data transfer performance. Care should be taken to
Document 38-08033 Rev. *D
Page 35 of 36
© Cypress Semiconductor Corporation, 2005. The information contained herein is subject to change without notice. Cypress Semiconductor Corporation assumes no responsibility for the use
of any circuitry other than circuitry embodied in a Cypress product. Nor does it convey or imply any license under patent or other rights. Cypress products are not warranted nor intended to be
used for medical, life support, life saving, critical control or safety applications, unless pursuant to an express written agreement with Cypress. Furthermore, Cypress does not authorize its
products for use as critical components in life-support systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress
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