Analog Devices Inc. EVAL-ADL8121 Evaluation Board

The Analog Devices Inc. EVAL-ADL8121 Evaluation Board consists of a 4-layer printed circuit board (PCB) fabricated from 10 mils thick, Rogers 4350B and Isola 370HR copper clad, forming a nominal thickness of 62 mils. The RFIN and RFOUT ports on the ADL8121-EVALZ are populated with Subminiature A (SMA) female coaxial connectors, and the corresponding RF traces have a 50Ω characteristic impedance. The ADL8121-EVALZ is populated with components suitable for use over the entire -40°C to +85°C operating temperature range of the ADL8121. The J1 and J2 connectors provide a through calibration path to calibrate board trace losses. J1 and J2 must be populated with RF connectors and capacitors to use the through calibration path.

The ADL8121-EVALZ ground path and RFOUT/VDD pin are accessed through the SMT test point connectors, GND and VDD. A supplementary test point for VBIAS is included for simple access on the RBIAS pin.

The RF traces on the ADL8121-EVALZ are 50Ω, grounded coplanar waveguide. The package ground leads and the exposed pad connect directly to the ground plane. Multiple vias connect the top and bottom ground planes with a 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 ADL8121-EVALZ represent the configuration used to characterize and qualify the device.