Hello,
I am currently using the AFSC5G23D37 Power Amplifier in my project, and it is working well with a second harmonic level of around -50 dBc. I decided to replace PA with the AFSC5G23E39, which has the same footprint, to see how it performs. After modifying the gate and drain voltages of the new PA according to the datasheet, the AFSC5G23E39 also worked fine, but its harmonic level was raised to around -20 dBc. Even when not forcing the PA into saturation, the second harmonic level is significantly higher (around 25 dB higher) than the AFSC5G23D37 under the same conditions. I manually altered the gate voltages one by one, but it didn't have any positive effect on reducing the second harmonic. I also swept the drain voltage, which didn't change the result either.
Do you have any suggestions for reducing the second harmonic level of the AFSC5G23E39? Are there any information or test reports available about the second harmonic levels of the AFSC5G23E39 under various frequencies, temperatures, and input power conditions?
