The ADPA7005-EVALZ consists of a two-layer printed circuit board (PCB) fabricated from a 10 mil thick, Rogers 4350B, copper clad mounted to an aluminum heat sink. The heat sink assists in providing thermal relief to the device as well as mechanical support to the PCB. Mounting holes on the heat sink allow attachment to larger heat sinks for improved thermal management. The RFIN and RFOUT ports on the ADPA7005-EVALZ are populated by 2.9 mm, female coaxial connectors. The respective RF traces have a 50 Ω characteristic impedance.
The ADPA7005-EVALZ is populated with components suitable for use over the entire −40°C to +85°C operating temperature range of the device. To calibrate board trace losses, a through calibration path is provided between the J1 and the J2 connectors. J1 and J2 must be populated with RF connectors to use the through calibration path. See Table 2 and Figure 3 for the through calibration path performance.
The power voltages, ground voltages, gate control voltages, and detector output voltages are accessed through two 8-pin headers (see Table 1 in the user guide).
The RF traces are 50 Ω, grounded, coplanar waveguide. Package ground leads and the exposed paddle connect directly to the ground plane. Multiple vias are used to connect the top and bottom ground planes with particular focus on the area directly beneath the ground paddle to provide adequate electrical conduction and thermal conduction to the heat sink.
The power supply decoupling capacitors on the ADPA7005-EVALZ represent the configuration that was used to characterize and qualify the device. There may be a scope to reduce the number of capacitors, but the scope varies from system to system. It is recommended to first remove or combine the largest capacitors that are farthest from the device.
