Gibson MM516, Руководство пользователя

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MM516
User's Manual
51
Revision 1.4 7-8-2011
Hardware Description Manual
PCB #1 – A micro-strip with a total length of 1.279” is used to connect the RF output pad of the MM516 module (pad 1) to a
horizontal surface mount SMA connector (Bohua SMA-50KWHT). The micro-strip goes a very short distance on the top layer
of the board before transitioning to the bottom layer using an .018” via with a hole size of .008”. Drawings of the top and
bottom layers are shown below. Vias alongside the micro-strip connect the two internal ground planes together.
Figure 27 Long Micro-Strip Trace
PCB #2 – Using a 4 layer PCB, a micro-strip with a total length of 0.500” is used to connect the RF output pad of the MM516
module (pad 1) to a PCB edge mounted SMA connector (Linx CONREVSMA003.062). The micro-strip is entirely on the top
layer of the PCB, Vias alongside the micro-strip connect the two internal ground planes together.
Figure 28 Short Micro-Strip Trace
Design Verification and Production Testing
The impedance of the mictro-strip RF trace must be measured on the bare printed circuit boards between pad 1 of the
MM516 module and the center mounting pad for the SMA connector using appropriate equipment (such as a Polar controlled
impedance test system). The impedance must measure 50 ohms +/- 10% in order for the PCB to be acceptable to use.