The evaluation board uses 4-layer construction with a copper thickness of 0.5 oz (0.7 mil) and dielectric materials between each copper layer.
All RF traces are routed on Layer 1 and all other remaining layers are grounded planes that provide a solid ground for RF transmission lines. The top dielectric material are Rogers 4350, offering low loss performance. The prepreg material in the middle is used to stick core layers together, which are RoHS compliant ISOLA 370HR layer with copper traces above and below. Both prepreg and the ISOLA 370HR core layer are used to achieve the required board finish thickness.
The RF transmission lines were designed using a coplanar waveguide (CPWG) model with a width of 18 mil and ground spacing of 13 mil for a characteristic impedance of 50 Ω. For optimal RF and thermal grounding, as many plated through vias as possible are arranged around the transmission lines and under the exposed pad of the package.
Since the HMC1048ALC3B is a passive device, there is no requirement for external components. The LO and RF pins are internally ac-coupled. The IF pin is internally dc-coupled. Use an external series capacitor when IF operation is not required. Choose a value that stays within the necessary IF frequency range. When IF operation to dc is required, do not exceed the IF source and sink current rating specified in the Absolute Maximum Ratings section.