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Low Noise Amplifiers Forum Discussions

pablogr
Level 1
Level 1
First reply posted First question asked Welcome!

Dear all,

We have had an issue with SPDT BGS12P2L6 which seems to be burned in our PCB.

We are currently using the SPDT to choose between two GNSS antennas, one external active antenna and another internal antenna using LNA BGA824N6.

I would like to confirm that there is no issue in using the LNA output as an input in the SPDT RF2 signal.

Thanks and kind regards.

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3 Replies
GeorgeT
Moderator
Moderator
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50 solutions authored 25 likes received 5 likes given

Hi @pablogr,

Please note that RF2 pin can be used as an input pin.

I would recommend to verify that the RF power levels at all the the RF ports are within the limit, 37 dBm, mentioned in the datasheet of BGS12P2L6. Also verify that there is no DC voltage at any of the RF ports.

Please let us know whether the issue is faced in single board or on multiple boards.

Thanks and regards,

George

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Dear @GeorgeT thanks for your feedback.

We are using it for GNSS, you can see the schematic attached to the firts post. Consdiering the signal strength for GNSS could by up to -120dBm, it is very difficult to achive the 37dBm, so I don't believe this would be the case. Thanks for pointing that out.

We are including a DC rejection cap between LNA and SPDT, just in case the LNA is providing any DC offset in the output.

Thanks and kind regards.

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GeorgeT
Moderator
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50 solutions authored 25 likes received 5 likes given

Hi @pablogr,

Thanks for the clarifications.

Please check/verify the following points

1. Board design and connections

2. Power and DC voltage requirements are met also in RF1 line.

3. CTRL voltage to BGS12P2L6 is also within the limits. 

4. Current levels are also within the limits as mentioned in the datasheet.

While testing set appropriate current compliances in the power supplies. Check if the current is rising in any of the lines.

Please share your findings.

Thanks and regards,

George

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