BS2px getting really hot!

Ross-O

Hi Guys,

New stamp user here. I just got my PDB and BS2px. I jumpered P0 to LED 0.
I then run the following code.

' {$STAMP BS2px}
Main:
HIGH 0
PAUSE 500
LOW 0
PAUSE 500
GOTO Main

The LED blinks as expected but after about a minute LT 1121A5 is too hot to put a finger on longer than about 5 seconds.

Is this expected behavior or do I have a problem.

No measureable increase in temp if I only download and run something like

' {$STAMP BS2px}
Debug "Nada"

Thanks,
Ross-O
www.diver.net/ross

Microman171

have you tried using differant pins. I use the BS2 so I wouldn't know whats happening, but try that and see if it does anything .

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1 + 1 = Window

/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
0............................................0
0............................................0
0.(Microman171@hotmail.com)..0
0............................................0
0............................................0
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

Ross-O

Any sort of I/O (LEDs, servo, input buttons) seems to make it get hot. Maybe it's expected behavior - I just hated to risk a $70 part without at least asking. It seems to reach steady state at 150F or so (guessing here, haven't measured it). It's been running for 30 mins and hasn't let the smoke out yet...

Bruce Bates

Ross -

So long as there is a resistor in line (in series) with any output load, per the PBASIC Stamp Manual, the pin port will generally be protected. If a resistor blows smoke (rather than the Stamp) what's the loss

If the voltage regulator gets overloaded, it will merely shut down. You're well advised to be careful as you're doing, but these really are well designed and sturdy devices! The only other thing I can think to do, is to carefully check the load on any used pin ports, and make sure that no portion of the PDB is touching any external parts (metal enclosue, tin foil, etc).

Passing thought - I wonder if in future incantations of the PDB (or other development boards) a series jumper on the output side of the voltage regulator makes some sense. At least then one could temporarily remove the jumper to check the total load being drawn? That may cause more trouble than it's worth however.

Regards,

Bruce Bates

Chris Savage

Hello,

·· The BS2px24 runs at 32Mhz in Turbo Mode.· In the surface mount package the temperature can run upwards of 140 degrees F at this speed.· This is normal when the chip is driving any load on the I/O pins.· With no load, I've measured 126 degrees F average temperature.· One thing you can check is to make sure your current draw (With nothing connected to the I/O pins or regulator) doesn't exceed 60mA.

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Chris Savage
Parallax Tech Support
csavage@parallax.com