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QMX not starting up

 

Hello everyone,

I recently built a QMX and I'm having some trouble getting it to run. I loaded the firmware, but it doesn't appear to get through the application initialization.??

I probed the PWM lines on the supply converter boards and there's never any activity, as if it's not getting to the point where it tries to start them up.

If I force the loader with the aux2 jumper, there is now an eeprom file in the drive, indicating it was running at some point.

Sorry if this was covered?already.. also wondering why my supply board #1 doesn't look like the photos.? It has a large SMBJ package next to C107 instead of the sot23 and chip resistors.. so I don't have a component placement diagram to identify some of the parts.

Any suggestions for next steps?

Thanks

Jeff
 

Hello Jeff,

how much current into the QMX and which voltage?

73, Ludwig
 

Hi Ludwig, these are some observations:

145mA at 9.0V input
135mA at 5.5V input (lowest voltage it seems to hold the power on state)
165mA at 9.0V input when running bootloader

If I remove power board #2 and press the button (so as to check 12v rail) I get 5mA at 9.0V

How do these numbers look?

Jeff
 

Is this a recent revision for board #1 that the documentation hasn't been updated with yet?? I thought I went through all the QMX pdfs and didn't see this component arrangement in any of them.
 

Hello Jeff,

it looks like the 3.3 V for the controller is delivered from the analog regulator. Its neccessary for the start. If the SMPS doesn't come up, the start procedure don't succed. (If the 3V3 SMPS is working, the current should be below 100 mA @ 12 V.)
But why???
In older cases there were missing or shortend solder points at the connectors from main PCB to the SMPS boards. Could you check this, also soldering both sides of the female header pin connector.

Could you load the firmware again?

73, Ludwig
 

Ok it seems to be running normally after loading it again.? I connected with the terminal and ran some of the hardware tests. May need to review some things in there before I close it up and start working with it.

Thanks

Jeff
 

Sounds good

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