AVRDragon VCC to GND Exhibits Low Resistance

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I was in the middle of debugging an app when, during another program cycle, my power supply's current limit lamp came on. A quick check revealed this to be from the Dragon. Measurements with a DMM indicates a 3ohm resistance between VTG and GND pins of the ISP header. At that time, the board was powered at 3.3V, off the same powersupply, limited to 30mA.

Can anyone with a working Dragon make the same measurement, and see if the readings are similar? Are the damn dragons that fragile?

Does this generally mean I need to get another Dragon? Or should I start looking at JTAGICEmkIIs?

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Hmm, replaced both the analog switches (NLAS2066) on the Dragon, resistance between VCC and GND in the few Kohms, but still no joy with contacting targets.

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Are you aware of this https://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&t=54390 thread? Hope you find the answer you are looking for.

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Quote:
resistance between VCC and GND in the few Kohms
What do you expect? What happens when you reverse the probes?

John Samperi

Ampertronics Pty. Ltd.

www.ampertronics.com.au

* Electronic Design * Custom Products * Contract Assembly

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32kohm forwards, 39.2kohm in reverse. I'm getting a signature of 0x535353 when contacting a target, and there is still a bit of a high current draw(100mA seems excessive).

I get this feeling that it might be time to get a jtagicemkii. Those don't die that easily, do they? Seeing as it's my second Dragon now.