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I am designing a circuit working from 9kHz~30MHz, including a few attenuators, two SPDTs and one amplifier, which all need some DC bias. I use some 10u 0805 MLCC capciators for coupled capciators in the signal transmitting microstrip. However, I found that even the amplifier could work normally from 9kHz to 30MHz, the throughout gain is varying from 0dB to 12dB as from 9kHz to 30MHz. So I test every step with open-ended coaxial cable, getting that the insertion loss of coupled capacitors causing the gain subtracted. So I use 10u 0805 capacitors, still having terrible loss. With larger value of capacitors, the loss becomes smaller. Now it comes to my question: the 0805 case MLCC capcacitors have a most value of 10u, so what effort should I make? Pursuing larger value capacitors or just make 10u capacitors parrelleled? Or would somebody tell me another way? Thanks.