Q: I’m not getting the expected gain from the HMC313 eval board above 3 GHz. Is this to be expected?
Q: I’m not getting the expected gain from the HMC313 eval board above 3 GHz. Is this to be expected?
A: The issue is caused by the design of the evaluation, specifically the location of the L1 bias induction. Ideally this inductor should touch down on the RF output trace. Instead the inductor is set back from the RF trace shown in Figure 1. This is causing significant gain roll-off above 3 GHz.
Figure 1. HMC313 Evaluation Board Layout
