John

Can you wait for these to cool down, then attach them to atomizer analyzer and post a screenshot? Something's reading wrong for certain.

Also, try reverting to 7/14 and see if the problem goes away. It could be a bug in 7/16.

Dwaindablane, what firmware are you using? 7/14 or 7/16? Druckle, does the reference resistance change (even with ohm lock on)? If it doesn't think it gets above 150F in the first portion of the fire, it will assume it is a kanthal coil and switch out of temperature control.

Oh I get what you're trying to do. The problem there is that atomizer analyzer is a special case. The DNA 200 only reads the resistance when it is firing or told to read it, otherwise it would sit there firing the coil all the time, which would waste a good bit amount of power. What atomizer analyzer does is it periodically requests a resistance sample from the DNA, and then displays the results of that sample. That said, there's no reason we can't add device monitor's live ohms (while firing) to the list of fields that could be displayed on the screen, if that would help.

Can you post a screenshot of this?

That said, it probably wouldn't hurt to display mk ore decimal points, it seems to be a point of confusion and there is usually plenty of free space on the graph.

Sure is, just set one of your three display fields to it Or plot it in device monitor.

That will charge (and is more or less how we did it on the 40) the problem is the simplistic approach doesn't prevent charging in the battery reversed case (conducts through the body diode), doesn't protect in the one cell reversed case (pack voltage 4v) and doesn't protect the balancer taps. I have our solution down to 5 Fets but I am still not 100% happy with it.

If you have a voltmeter, what voltage do you get when reading between the solder joints of the 1 and Gnd tap connections? Then what voltage do you get between the far side of the resistors closest to the side? Everything looks pretty textbook except the GND tap solder joint, but that doesn't look so egregious as to be making no contact. What's your serial number? I can see if the production data for your board shows anything unusual, but the board looks right to me.

KFC can you post a higher resolution picture of the area around the USB ports and the balancer? It has to be one of the outside two resistors in that set of four, or the balancer lead.

Ktmrider, take a stab at it, and if you can't sent it in and we'll fix it. Or just send it in, but soldering 0402s isn't too bad.

Ah, this is an easy one. You have way too much solder on the top-most tap connector pin (GND), it is shorting out the cell one sense line. Remove the extra solder and you should be good.

What cell voltages are you reading in device monitor when you try to fire while connected to USB? Also, what firmware revision?

We've seen that if the resistor in the corner of board got knocked off. can you post a picture of the front of your board?

Have you tried connecting a battery, or just USB? If it doesnt turn on with a battery (or power supply) either then PM me your address and I'll swap it for another one so we can see what's going on with yours.

Huh. I would have figured it would be higher.

If you go into EScribe, go to help, go to About, then left click on the logo seven times, that will turn on debug options. After that, go into Device Monitor and see what your bandgap is reading. I bet it is reading high.

That all looks pretty reasonable. There's basically zero capacity difference in a LiFePO4 pack between 3.6 and 3.35 volts, so if it stays nicely balanced throughout the rest of the range (3.30-3.30-3.29 is fine) then I wouldn't worry about it.

Does the board work and just not talk to USB, or does it not turn on at all?

Actually, before you send it back (your new one is already on the way, but if we get this figured out and you end up with two, merry christmas) try pulling the output wire off the board and see if it still auto-fires. The large exposed silver via you circled won't cause the board to auto-fire, but if your output wire was shorted to the smaller green-covered via next to it, that absolutely COULD cause what you're seeing.

No, I believe the case analyzer results. I mean how long have you been running the DNA 200? Firmware prior to 7/9 could cause chip damage in rare circumstances that we've seen cause excessive heating, but if yours has never been run with firmware that early that would be cause for greater concern.

We like Ersa I-con stations and use a no clean SAC305 for everything. But we have had to be lead free for so long I don't even remember what leaded solder acts like. Kester 951 is the stuff if you need liquid flux, definitely.

You should have a replacement board arrive Friday, and a UPS label to send your existing one back so we can see where it is getting the fire signal from.

Can you set up a graph of all three cell voltages in device monitor, then take a couple puffs and post the screenshot? We'll be able to see if it is a bad cell and if so, which cell.

If it is showing voltage on the button while it continues to perma-fire, then that is going to be a hardware issue. PM me your address and I'll get another one and a return tag out to you today, so I can see what's going on with that one. Thanks John