AD8368 OIP3 measurement

Document created by analog-archivist Employee on Feb 23, 2016
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I am testing OIP3 with f1=71MHz, f2=70MHz, 0dbm per tone signal, Vmode=0V. In
terms of Figure 10, Vgain is 0~1.0V, the IOP3 should be about 34dbm. But I got
the 30dbm when Vgain is 0 ~ 0.9v; 34dbm when Vgain is 1.0V. Could you please
explain how I can get the result as Figure 10?


What are your values for the DECL and HPFL caps?  Those can have an effect on
OIP3; basically, if they are not big (small) enough, they can either improve or
degrade the OIP3.  I would suggest using the caps values on our evaluation
board for 70 MHz operation.