SMA to RJ45 adapter

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The SMA to RJ45 adapter board is used, primarily in the lab, to convert single-ended analog signals into a differential format suitable for the ADC16x250-8_RJ45_rev_1 board.

[ADC16x250 rj45 cross corr tests] describes an example of how this board is used in the lab.


Block Diagram

SMA to RJ45 adapter test board

  • designed and built for use by the LWA project; Documented here for convenience only.
  • 16 vertical launch SMA socket connectors for single ended test signals and 4 RJ45 connectors to drive 4 CAT7 cables.
  • A 1:2 balun is used for each of the 16 test inputs. Different baluns may be used based on the degree of optimization for operation at a particular operating frequency. Or not.
  • All 16 differential pairs are output over a total of 4 RJ45 connectors to CAT7 cables..
  • Tyco Electronics 4way CAT5E RJ45 connector
  • CAT7 shielded RJ45 cables. Here's an example 3 ft yellow cable.
  • All 16 of the baluns are on the top side of the PCB.
  • 8 of 16 differential pairs from the baluns to the RJ45s are on the top side of the PCB. The remaining 8 are on the bottom. This way the interpair isolation is increased as well as easing the routing to the RJ45 connector.
  • SMA center pin to SMA center pin spacing is about 11/16 inch or 0.6875 inches.
  • The SMA connectors are on the opposite side of the PCB as the corresponding etch and balun to minimize the transmission line stub at the SMA launch.
  • The board is roughly 9.5 inches by 1.9 inches.


place and route

design files


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