|2R 6dB Power Splitter with Matching Network for LTC5587|
|Unit #2 using a 2R divider (upper right between U103 and SMA) and 50 ohm matching network at meter (lower right to the right of the LTC5587 at U105).|
|Power Meter Response 40MHz - 1000MHz.|
|Power Meter Response 1000MHz - 2000MHz|
|Power Meter Response 2000MHz - 3000MHz|
The slope and intercept are both a little higher than the nominal value from the datasheet. They actually look closer to some of the higher temperature data listed. My guess is I didn't get the QFN paddle soldered sufficiently well to make a good thermal junction and the part is running warm.
A couple of different 50 ohm matching configurations were tried. No matching (device direct) worked well in the sub 1GHz region and increased sensitivity, however, above this the results were not usable. A 2.2nH serial inductor with no shunt capacitor was tried. This produced good results through 2GHz (not much difference than the above except the >1900MHz results were closer to the B=-43dBm line).