TN_121 FT245R Errata Technical Note

TN_121 FT245R Errata Technical Note
Document Reference No.: FT_000256
Version 1.0
Issue Date: 2010-11-05
The intention of this errata technical note is to give a detailed description of known functional or electrical
issues with the FTDI FT245R devices.
The current revision of the FT245R is revision B, released May 2007. At the time of releasing this
Technical Note there are no known issues with this silicon revision.
Future Technology Devices International Limited (FTDI)
Unit1, 2 Seaward Place, Centurion Business Park, Glasgow G41 1HH United Kingdom
Tel.: +44 (0) 141 429 2777 Fax: + 44 (0) 141 429 2758
E-Mail (Support): [email protected] Web: http://www.ftdichip.com
Copyright © 2010 Future Technology Devices International Limited
Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
TABLE OF CONTENTS
1
FT245R Revision .................................................................................... 2
2
Errata History Table – Functional Problems........................................ 3
2.1
3
Functional Problems of FT245R ........................................................... 4
3.1
Revision A ............................................................................................................ 4
3.1.1
PWREN# pulses during enumeration ...................................................................................... 4
3.1.2
BitBang Mode Variable Pulse Width........................................................................................ 4
3.1
4
Errata History Table – Electrical and Timming Specification Deviations. ...... 3
Revision B ............................................................................................................ 5
Electrical and Timing specification deviations of FT245R ................. 6
4.1
4.1.1
4.1
Revision A ............................................................................................................ 6
VCCIO cannot be set below 2.6V ............................................................................................ 6
Revision B ............................................................................................................ 6
5
FT245R Package Markings.................................................................... 7
6
Contact Information............................................................................... 8
Appendix C – Revision History ................................................................. 10
Copyright © 2010 Future Technology Devices International Limited
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Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
1
FT245R Revision
FT245R part numbers are listed in Error!
code identifies the device revision.
Reference source not found.. The letter at the end of date
The current revision of the FT245R is revision B, released May 2007. At the time of releasing this
Technical Note there are no known issues with this silicon revision.
Part Number
Package
FT245RL
28 Pin SSOP
FT245RQ
32 Pin QFN
Table 1 FT245R Part Numbers
This errata technical note covers the revisions of FT245R listed in
Error! Reference source not
found..
Revision
Notes
A
First device revision
B
Second Device revision
Table 2 FT245R Revisions
Copyright © 2010 Future Technology Devices International Limited
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Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
2
Errata History Table – Functional Problems
Functional
Problem
Errata occurs in
device revision
Short description
PWREN# signal will not be stable during enumeration – 3
FT245R
A
pulses.
2.1 Errata History Table – Electrical and Timming Specification
Deviations.
Deviations
FT245R
Short description
Errata occurs in device revision
Cannot set VCCIO below 2.6V
due to internal RESET# pullup
Copyright © 2010 Future Technology Devices International Limited
A
3
Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
3
Functional Problems of FT245R
3.1 Revision A
3.1.1 PWREN# pulses during enumeration
Introduction:
PWREN# is an output to signal if the device is enumerated and awake (logic 0) or if it is in reset/suspend
(logic 1)
Problem:
During enumeration the pins were configured as outputs and as a consequence of the 3 resets required
during enumeration the device toggled 3 times giving a false indication that the device was ready to use.
Workaround:
There are no known workarounds available. This issue will be corrected at silicon revision B.
Package specific:
The effected packages are listed in Table 3.
Package
Applicable (Yes/No)
FT245RL
Y
FT245RQ
Y
Table 3
3.1.2 BitBang Mode Variable Pulse Width
Introduction:
BitBang is a mode the device may be put into to allow free running data to be clocked in/out of the
device without any control bits.
Problem:
The output may be clocked out at different speeds to allow for different pulse widths. However this
clocking stage is not synchronized with the incoming data and can result in the pulse widths varying
unexpectedly on the output.
Workaround:
Set the clock divisor to 1 (baud rate = 3,000,000) and pad the data field with extra 1’s or 0’s to achieve
the required pulse width for each bit.
Copyright © 2010 Future Technology Devices International Limited
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Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
Package specific:
The effected packages are listed in Table 4.
Package
Applicable (Yes/No)
FT245RL
Y
FT245RQ
Y
Table 4
3.1 Revision B
There are no known new functional issues specific to revision B.
Copyright © 2010 Future Technology Devices International Limited
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Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
4
Electrical and Timing specification deviations of FT245R
4.1 Revision A
4.1.1 VCCIO cannot be set below 2.6V
Introduction:
The FT245R device is specified to handle IO down to 1.8V.
Problem:
The FT245R device contains an internal pullup (200k) on RESET#. This is wired to VCCIO and not VCC.
If VCCIO is below 2.6V the device will not come out of reset.
Workaround:
There are no known workarounds available. This issue will be corrected at silicon revision B.
Package specific:
The effected packages are listed in Table 5
Package
Applicable (Yes/No)
FT245RL
Y
FT245RQ
Y
Table 5
4.1 Revision B
There are no known functional problems with revision B.
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Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
5
FT245R Package Markings
FT245R is available in two RoHS Compliant packages, 32 pin QFN and 28 pin SSOP. An example of the
markings on each package is shown in
Figure
5-1..
YYXX-A Where YY is 2 digit year code, XX is 2
digit week code and -A is the revision
XXXXXXXXXXXX is the manufacturing
LOT code
Figure 5-1 Package Markings – 28 SSOP
YYXX-A Where YY is the 2
digit year code, XX is 2 digit
week code and -A is the
revision
XXXXXXXX is the
manufacturing LOT
code
D7
Figure 5-2 Markings – 32 QFN
Copyright © 2010 Future Technology Devices International Limited
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Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
6
Contact Information
Head Office – Glasgow, UK
Future Technology Devices International Limited
Unit 1, 2 Seaward Place, Centurion Business Park
Glasgow G41 1HH
United Kingdom
Tel: +44 (0) 141 429 2777
Fax: +44 (0) 141 429 2758
E-mail (Sales) [email protected]
E-mail (Support) [email protected]
E-mail (General Enquiries) [email protected]
Web Site URL http://www.ftdichip.com
Web Shop URL http://www.ftdichip.com
Branch Office – Taipei, Taiwan
Future Technology Devices International Limited (Taiwan)
2F, No 516, Sec. 1 NeiHu Road
Taipei 114
Taiwan, R.O.C.
Tel: +886 (0) 2 8797 1330
Fax: +886 (0) 2 8751 9737
E-mail (Sales)
[email protected]
E-mail (Support)
[email protected]
E-mail (General Enquiries) [email protected]
Web Site URL
http://www.ftdichip.com
Branch Office – Hillsboro, Oregon, USA
Future Technology Devices International Limited (USA)
7235 NW Evergreen Parkway, Suite 600
Hillsboro, OR 97123-5803
USA
Tel: +1 (503) 547 0988
Fax: +1 (503) 547 0987
E-Mail (Sales)
[email protected]
E-Mail (Support) [email protected]
E-Mail (General Enquiries) [email protected]
Web Site URL
http://www.ftdichip.com
Branch Office – Shanghai, China
Future Technology Devices International Limited (China)
Room 408, 317 Xianxia Road,
ChangNing District,
ShangHai, China
Tel: +86 (21) 62351596
Fax: +86(21) 62351595
E-Mail (Sales): [email protected]
E-Mail (Support): [email protected]
E-Mail (General Enquiries): [email protected]
Web Site URL: http://www.ftdichip.com
Copyright © 2010 Future Technology Devices International Limited
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Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
Distributor and Sales Representatives
Please visit the Sales Network page of the FTDI Web site for the contact details of our distributor(s) and
sales representative(s) in your country.
Neither the whole nor any part of the information contained in, or the product described in this manual, may be adapted or reproduced
in any material or electronic form without the prior written consent of the copyright holder. This product and its documentation are
supplied on an as-is basis and no warranty as to their suitability for any particular purpose is either made or implied. Future Technology
Devices International Ltd will not accept any claim for damages howsoever arising as a result of use or failure of this product. Your
statutory rights are not affected. This product or any variant of it is not intended for use in any medical appliance, device or system in
which the failure of the product might reasonably be expected to result in personal injury. This document provides preliminar y
information that may be subject to change without notice. No freedom to use patents or other intellectual property rights is implied by
the publication of this document. Future Technology Devices International Ltd, Unit 1, 2 Seaward Place, Centurion Business Park,
Glasgow G41 1HH United Kingdom. Scotland Registered Number: SC136640
Copyright © 2010 Future Technology Devices International Limited
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Document Reference No.: FT_000256
TN_121 FT245R Errata Technical Note
Version 1.0
Clearance No.: FTDI# 183
Appendix C – Revision History
Version 1.0
First Release
05/11/2010
Copyright © 2010 Future Technology Devices International Limited
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