I have a setup like this;
PlutoSDR Tx (Freq: 2.45 GHz, Pout: -20 dBm) ------> TSS-53LNB+ LNA (Gain: 19 dB, Pout: -1 dBm) ------> CN0417 (Gain: 21 dB, Pout: 20 dBm)
With this setup, the EVM is around %1.7, without LNA, around %4. So this is why I used LNA to reach -1 dBm Pout. The tx signal is single carrier by the way.
But yesterday I burned my two CN0417s in the test setup. I've measured the CN0417(with beeper), the USB power stage seems OK.
Then I removed the E1 ferrite to disconnect power stage and RF stage. LTM8045 seems OK. I get clear 5V. But the whole RF stage is short circuit to GND.
Then I removed the ADL5606 and measured the PCB again. The RF filter(FL1) and all capacitors are OK except CIN.
Also, ADL5606 is short circuit from RF_IN to RF_OUT between GND (measured after desoldered from PCB).
I do not know how this happens, because I did not exceed the maximum ratings of ADL5606 (maximum Pin: 18 dBm). Even if I exceed, the LTM8045 gives maximum 450mA
and the ADL5606 consumes 540mA to run around 30dBm Pout. So the LTM8045 should not supply this. And maybe should burned because of overload (but seems OK).
Maybe CIN cap burned first then it burned ADL5606 but is a 50V capacitor. I should not be burned easily.
Could you help me to realize why and how this happens?