Hi everybody,
after the trouble I've had with my first Beagleboard (the MMC card
could not be found, for details see here
http://groups.google.com/group/beagleboard/browse_thread/thread/9763cfdd991628cc
) I have received a replacement today. Well, it works even less than
the old board.
While serial communication worked on my first board and the splash
screen could be seen via DVI nothing but the power LED works on the
new one. I have measured the current. the old board consumes 356 mA
while the new one consumes a massive 800 mA doing nothing. Furthermore
the S-Video socket becomes warm on the new board.
Request an RMA. I will personally check out the board before we send it to you. Make sure that you are powering the board from a 5V power supply. The symptom you describe is what you will find if you power the board from a voltage higher than 5V.
Gerald
Request an RMA. I will personally check out the board before we send it to
you. Make sure that you are powering the board from a 5V power supply. The
symptom you describe is what you will find if you power the board from a
voltage higher than 5V.
As a matter of interesst just how sensitive is this? I have been using a chip
called TDA8138 which provides a 5.1V supply and a switchable 12V supply
(switchable with a TTL signal). Currently I am using an Arduino, but if I
needed something with more umph could I use a BeagleBoard? Or would
I have to find a way to loose 0.1V?
David
The maximum is 5.2V. That is also what is required by the USB voltage as well. If you don’t need 5V for USB, then you can operate the board down to 3.3V. A stable 5.1V rail should not be an issue to operate the board. The issue comes up when the supplies are not well regulated and the voltage goes up to a much higher voltage causing damage to the board.
Gerald.
Hi Gerald,
thanks for the reply. It is an EBV Beagle, so I assume you don't get
in contact with my RMA. I am currently considering returning the board
altogether. When I first ordered it in May (!) it seemed like a useful
contribution to my PhD project but now, for months down the line and
underwhelmed by the product I have to stop playing around and have to
get cracking...
At first, I have used the power supply which was included with the
board. To measure the current I have used a regulated laboratory power
supply which was set to precisely 5,0 V
Alex
You are correct EBV has their own deal. But, I will swap it out anyway. They have not had anymore built for a long time now, so I am not sure where this one came from. My concern is that they may have sent you a bad board that had already been returned or something. I have no idea how they do RMAs or where they get them repaired. They definitely don’t do it the way we do.
Gerald
The maximum is 5.2V. That is also what is required by the USB voltage as
well. If you don't need 5V for USB, then you can operate the board down to
3.3V. A stable 5.1V rail should not be an issue to operate the board. The
issue comes up when the supplies are not well regulated and the voltage
goes up to a much higher voltage causing damage to the board.
Thank you, I suppose I could always use the forward voltage drop from a
diode to drop it to a safe level. I think I might even do that with the
arduino just for safety.
David
This is excellent news for me also! I have located a couple of regulator
solutions that provide 5.1V outputs. Now that I know 5.1V is OK, I can proceed
to add my Beagle to my robot. I can plug my battery into the regulator board
and the output of the regulator board directly into Beagle's DC power jack.
I also have a simple 5V breadboard power supply I believe I can modify to
take a battery input and connect to the Beagle. I just need to change the
input connector to be compatible with my battery packs and add a DC power plug
to the output.
8-Dale