Something really strange just happened using my Arduino Duemilanove. First just note that nothing has been re-soldered, re-wired anything. I haven't even changed my code.
When connecting the Arduino to the PC to upload my new sketch received an error saying that "usb 0" was not found. I unplugged it within less than a minute and by chance touch the bottom of my Arduino and it was warm (the source of the heat was the chip in front of the USB hub labelled FYDI). I quickly went to check my motor driver (TB6612FNG) and it was extremely hot, it actually burnt my skin.
To answer some questions, no I was not powering the motor with my Arduino and yes the power source is separated from the Arduino and both current and voltage ratings are well within range.
Any help would be appreciated, I am a little scared to try again.
If the FTDI chip is getting hot on a Duemilanove chances are good you somehow damaged the +3.3V output of the Arduino, since that came directly from the FTDI chip (this was fixed on the Uno, and it now comes from a dedicated voltage regulator).
So...did you have +3.3V connected to something? Did it short out by accident?
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The Ruggeduino: compatible with Arduino UNO, 24V operation, all I/O's fused and protected
Thanks for the reply magician, it was not power at all before I connected the usb cable.
I plucked up the courage to see if it gets hot again, it doesn't but I now get "avrdude: stk500_recv(): programmer is not responding". I fear I may have just lost my dearest friend =(
@ RuggedCircuits, do you guys have a supplier in South Africa?
Nope, but we can ship there for fairly low cost.
The 3.3V was connected to the driver, the driver worked perfectly last week though.
Ah....why was 3.3V connected to the driver? Unfortunately, that now sounds like the most likely explanation. If the driver was getting so hot as to burn you, it is possible that there was something wrong (shorted outputs? overcurrent?) When a chip fails, it can take down other chips with it. If the driver had +3.3V connected to it and the driver failed, it is possible it shorted out the +3.3V node (or applied 5V, 12V, whatever voltage your motors work with) to it and destroyed the FTDI device.
I think it's time to buy a new friend You can try replacing the FTDI chip but it's fairly difficult to do unless you have experience with surface-mount rework.
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The MegaRAM shield: add 128 kilobytes of external RAM to your Arduino Mega/Mega2560
The data-sheet showed the VCC pin to 3.3V. The battery is 3.7V powering the motors.
I forgot to mention as part of the same project I was using a 5DOF board from sparkfun which returned incorrect readings. Again the 5DOF worked perfectly the previous times with no change to the wiring. Another symptom of the same problem?
GregN,
Sounds like its time for you to create your own arduino functionality.
There is not much to connect really.
Add a 5v regulator and a 3.3V regulator at whatever current levels you need.
Use a seperate FTDI-Basic or a CP2102 based board as the USB/Serial adapter connected to D0/D1 (Rx/Tx) and with a 100nF cap from the DTR line to the reset pin.
It's entirely possible it's the same problem, but it's hard to give definitive answers without details. I'm guessing you'd like to prevent this happening in the future. Can you sketch out how you have everything wired, what part numbers you are using (I don't know many motor drivers that will work with 3.7V motor voltages).
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The Flexible MIDI Shield: MIDI IN/OUT, stacking headers, your choice of I/O pins
It looks like that motor driver needs a minimum motor voltage of 4.5V (see datasheet page 3, parameter "Supply Voltage VM"). With only 3.7V you were probably not turning on the driver's internal transistors strongly enough, which explains why it was getting so hot.
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The Gadget Shield: accelerometer, RGB LED, IR transmit/receive, speaker, microphone, light sensor, potentiometer, pushbuttons
Thanks! That actually makes perfect sense, I hope all Rookies go through this! And that by the time I start my EE Engineering degree (my university doesn't allow Com Sci and EE Eng to be taken simultaneously) I hope I have made all the possible mistakes already!
You can try replacing the FTDI chip but it's fairly difficult to do unless you have experience with surface-mount rework.