wiken
New Member
Posts: 45 
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Post by wiken on Nov 10, 2017 15:04:17 GMT
Hi.
We need to rebuild our boards to 3.3V. According to documentation 2 resistors needs to be changed. Do you have any info regarding this? Best Regards \Wiken  |
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wiken
New Member
Posts: 45
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Post by wiken on Nov 13, 2017 11:20:29 GMT
Hi again. Or is it possible to order box of 10 or 25 premade as 3.3V TCX275? Best Regards \Wiken |
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Post by Admin on Nov 14, 2017 15:44:42 GMT
Let me check!
We have converted a few and it is not too difficult.
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Post by Admin on Nov 14, 2017 15:53:59 GMT
Here is the schematic excerpt that shows how to convert to 3V3 operation.
3v3Conversion.pdf (606.74 KB)
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wiken
New Member
Posts: 45
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Post by wiken on Nov 15, 2017 8:14:47 GMT
Great, thank you for your support.
I must ask:
According to the schematics, if one adds R519 and D507, the feature of NOT powering the board with USB is lost.
And the note: Do not populate with JP501.
Is there a special reason for this design choise for 3V3?
in ShieldBuddyPinoutRevB_UM_2 the top layout view is quite unreadable, the bottom layout view is much better. Do you have a better top layout picture?
Thanks in advance.
\Wiken |
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Post by Admin on Nov 17, 2017 13:31:59 GMT
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Post by hd9919 on Mar 14, 2018 14:42:49 GMT
Hi,
I tried to get my ShieldBuddy to work with 3.3V. First I tried to directly power the middle Pin of the jumper with the 3.3V from what i saw on the diagram posted above this should be possible, however the red reset LED is constantly on. Same goes for the modified linear regulator.
Is there anything i have to consider regarding the software?
thanks for your help!
Dominic
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Post by Admin on Mar 14, 2018 14:52:24 GMT
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Post by hd9919 on Mar 14, 2018 15:07:29 GMT
Here is the schematic excerpt that shows how to convert to 3V3 operation.
I cannot access the link. But I did the modifications mentioned above: - R520 -->54.9 kOhm . - R519-->0 Ohm. - no jumper connected I get 3.3V at the 5V Pins and also on the TC275 Pins 153 (Vext), 154 (VDDP3) and 155(VDDFL3). But the program which was running at 5V wouldn't run at 3.3V and the red reset LED is constantly on. Thanks for your help. |
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Post by Admin on Mar 14, 2018 15:12:57 GMT
Can you still re-program the TC275 FLASH?
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Post by hd9919 on Mar 14, 2018 15:37:44 GMT
No the usb is no longer recognized by my computer
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Post by Admin on Mar 16, 2018 12:40:10 GMT
Did you fit diode D507?
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Post by mariotheissl on May 22, 2018 12:05:28 GMT
I have the same problem as descriped by hd9919. The red led is constantly on and I do not get any access to the board with the usb interface. I did all changes on the board, I also added the D507 diode
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wiken
New Member
Posts: 45
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Post by wiken on Oct 24, 2018 10:58:55 GMT
Hi. I can verify that the rebuild works fine. Do however follow both schematics and replace the reset-chip. My first TC broke after rebuilding with first schematics. I did rebuild it using the second schematics too, and replaced the reset-chip. But that one uses lots of amps, broken. My advice, don't start it up after half rebuild. After rebuild of a second one, all is fine and it works great. \Wiken |
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