Difference between revisions of "Trace board design recommendations"

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The most common recommendations are as follows:
 
The most common recommendations are as follows:
  +
* We recommend to design the following pin interface: [https://wiki.segger.com/19-pin_JTAG/SWD_and_Trace_Connector Trace Pinout]
  +
* Use all 4 trace data signals to avoid overflows.
 
* All trace transmission lines should be as short as possible and have ideally the same length
 
* All trace transmission lines should be as short as possible and have ideally the same length
 
* Shielded transmission lines can reduce the impact of crosstalk
 
* Shielded transmission lines can reduce the impact of crosstalk
 
* Impedance matching of the transmission lines can improve the signal quality drastically
 
* Impedance matching of the transmission lines can improve the signal quality drastically
* Serial termination resistors should be considered for long lines transmission lines
+
* Serial termination resistors should be considered for long transmission lines
 
* Do not use any capacitive or inductive elements which are connected to the trace lines e.g. diodes, LEDs, capacitors, inductors etc.
 
* Do not use any capacitive or inductive elements which are connected to the trace lines e.g. diodes, LEDs, capacitors, inductors etc.
 
* Avoid stubs which create parasitic impedance changes and reflection
 
* Avoid stubs which create parasitic impedance changes and reflection
 
* Avoid multi usage of trace pins with other ICs which again will cause unwanted impedance changes and reflection
 
* Avoid multi usage of trace pins with other ICs which again will cause unwanted impedance changes and reflection
  +
* If your trace lanes are not shielded, make sure they do not propagate close to elements which can generate electro-magnetic waves e.g. motors or antennas
   
 
For design reference our [https://www.segger.com/products/debug-probes/j-trace/accessories/trace-reference-boards/overview/ Trace Reference Boards] can be used.
 
For design reference our [https://www.segger.com/products/debug-probes/j-trace/accessories/trace-reference-boards/overview/ Trace Reference Boards] can be used.

Latest revision as of 09:37, 30 October 2023

When designing trace boards additional design considerations need to be taken into account to make sure that a clean and noise free signal can propagate from the target device to the trace probe.

The most common recommendations are as follows:

  • We recommend to design the following pin interface: Trace Pinout
  • Use all 4 trace data signals to avoid overflows.
  • All trace transmission lines should be as short as possible and have ideally the same length
  • Shielded transmission lines can reduce the impact of crosstalk
  • Impedance matching of the transmission lines can improve the signal quality drastically
  • Serial termination resistors should be considered for long transmission lines
  • Do not use any capacitive or inductive elements which are connected to the trace lines e.g. diodes, LEDs, capacitors, inductors etc.
  • Avoid stubs which create parasitic impedance changes and reflection
  • Avoid multi usage of trace pins with other ICs which again will cause unwanted impedance changes and reflection
  • If your trace lanes are not shielded, make sure they do not propagate close to elements which can generate electro-magnetic waves e.g. motors or antennas

For design reference our Trace Reference Boards can be used.