Using Oscilloscopes and Logic analyzers on fine smt devices

Generally I either press the point of the probe into the solder next to a component lead, or I solder a bit of wire-wrap wire & clip on to that. It puts a whole new meaning on "hairy debugging task".

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Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html

"amerdsp" a écrit dans le message de news: snipped-for-privacy@q3g2000prf.googlegroups.com...

For ICs, down to around 0,65mm or even 0,5mm pitch, you can find "nano clips" distributed by Digikey (see page 1969 on their catalog). Not cheap but great. Robert

Sorry for it maybe offtopic.

If your chip has a JTAG support, instead of oscilloscope/logic analyzer you may use boundary-scan tools. In this case you do not have to touch pins at all. The universal software for manual boundary-scan: Scanseer at

When I'm laying out the PCB, I put 30 mil ICT test points on every net. These are easy to solder to :)

I got some testclips from pomona electronics, these should even handle

0.3mm pitch. I already used them on 0.5, no problem. But these clips are not at all cheap. But spending time soldering wires to 0.5 and cleaning up mistakes is more expensive in the end.

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Stef    (remove caps, dashes and .invalid from e-mail address to reply by mail)

And thats the right way to go for prototypes. Finished products are easy to debug with maginifer and sharp solder tip.;-)

ali

Absolutely not a prototyping technique - it is a mass production technique. The board is tested by a large bed-of-nails fixture at very high speed, after going through reflow and/or wave, and before depanelization.

We found .3 mm nanoclips a year or so ago. Not sure of the current price, but they were a lot less expensive than others at the time.

.3mm clips, $7.00ea

Scott