Data Sheet ADRF5044
Rev. 0 | Page 13 of 14
PROBE MATRIX BOARD
The probe matrix board is a 4-layer board that uses a 12 mil
Rogers RO4003 as the top dielectric material. The external
copper layer is 0.7 mil, and the internal copper layers are
1.4 mil. The RF transmission lines were designed using a
CPWG model, with a 16 mil width and a ground spacing of
6 mil, to have a characteristic impedance of 50 Ω.
Figure 26 shows the cross sectional view of the probe matrix
board, and Figure 27 shows the top view of the probe matrix
board. Measurements were made using 535 µm GSG probes at
close proximity to the RFx pins. Unlike the ADRF5044-EVA L Z,
probing reduces reflections caused by mismatch arising from
connectors, cables, and board layout, resulting in a more
accurate measurement of the performance of the ADRF5044.
RO4003
1oz Cu (1.4mil)
1oz Cu (1.4mil)
0.5oz Cu (0.7mil)
0.5oz Cu (0.7mil)
0.5oz Cu (0.7mil)
0.5oz Cu (0.7mil)
FR4
FR4
W = 16mil
G = 6mil
T = 0.7mil
H = 12mil
TOTAL THICKNESS ≈ 62mil
16313-026
Figure 26. Probe Matrix Board (Cross Sectional View)
Figure 27. Probe Board Layout (Top View)
RF traces for a through reflect line (TRL) calibration are
designed on the board itself. A nonzero line length compensates
for board loss at calibration. The actual board duplicates the
same layout in matrix form to assemble multiple devices at
once. Insertion loss and input and output return losses were
measured on this probe matrix board. Isolation performance
measured on the probe matrix board is limited due to signal
coupling between the RF probes that are in close proximity.
Therefore, RF port to port isolation was measured on the
ADRF5044-EVA L Z .
