QUESTION

Question

Hi - I have a m20050 on a custom PCB. I have it pushing comms over uart to an arduino to see what it's reporting. It reports the GPS sentences back but never finds any satellites visible even outside in open air. There is nothing else on the PCB except the m20050 and supporting components as per the sample circuit in the datasheet. What should I look for as to the problem? Could there be a dry joint or other soldering issue that might cause the chip to be powered, report NMEA sentences correctly over TX/RX but never find a satellite?

Thanks!

Answer 1

Hello Naz_st,

I believe you are on the right track with a possible reflow issue with the solder possibly shorting one of the pads or not making sufficient contact via cold solder joints. The next steps to check would be to re-check the instructions on the data sheet under the External Matching section to verify there's no post integration de-tuning. I'd start with those suggestions and check back if you're still having issues.

Thanks,

Dan

Comments

The circuit I'm using is the exact schematic from the datasheet (see below), with nothing else on the PCB (except pin headers to connect to external IC, and those well away from the antenna) and no enclosure.  I have included the 1.8nH inductor as specified in the example circuit... is it possible this is not needed and I should 0Ohm Res the junction instead?

Answer 2

Hi, the internal antenna requires a tuning circuit to ensure its on tune with the GNSS frequency bands. I think the first step would be to have your PCB files checked by Antenova support. Please can you contact techsupport@antenova.com

Thanks

Comments

Thanks - it's the same circuit as in the datasheet, but I'll send the PCB files to support as you suggest and see if they spot anything off about it.

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Was this issue resolved? I am also having the same problem. Followed the PCB and circuit design in the datasheet, am able to watch the MNEA messages on the UART, but GSV indicates no satellites.

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Hi,

As far as we know this issue was resolved, I would suggest we go through the same process, checking your layout first. Please contact techsupport@antenova.com so we can put you in touch with your regional support engineer.

Many Thanks

Steve