Generating a Test Point Report
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The test pad report is one of the sections we need in your design file. This has at a minimum the position and net for each probe that will be placed.
| x | y | net |
|---|---|---|
| 102.1 | 52.3 | GND |
| 21.4 | 22.1 | +5V |
| 102.1 | 52.3 | GND |
| 19.1 | 50.9 | SWCLK |
| 102.1 | 52.44 | SWDIO |
| 102.1 | 54.98 | SDA |
| 102.1 | 57.62 | SCL |
| 32.1 | 12.3 | GND |
One simple way to generate this is to use the centroid file (AKA pick-n-place file). There are some limitations as the net will need to be added manually to the standard format and test points can only be extracted if they’re a single pad.
There are tools for most EDA systems that will automatically create this report. Here are a few resources:
- KiCAD: This is a GPL3 licensed command line tool. You identify the pad number and ref des of the part and it spits out a spreadsheet already properly formatted. We also have a plugin available in the KiCAD content manager. See our blog post for more.
- Proteus: They have a blog post here also.
- Pulsonix: Pulsonix has a powerful report generation engine that include test points.
- PADS Professional
- Cadence
- Altium
- Allegra / OrCAD
- CADSTAR: Start on page 123 of the PDF.
- TARGET 3001!
- EasyEDA
- Diptrace & Eagle / Fusion 360 Electronics: No automatic tool available. The centroid file or gerber method should be used.
How to Include a Test Point Report in a Project
The test point report is one of the sheets of the design spreadsheet. The sheet should be named “probes” or “test points”.
Advanced Options
The test point report has a few options that can be used to customize your design. All available fields are described below:
| Field(s) | Description | Required? |
|---|---|---|
| x & y | Position of the test point in the same units and coordinates as the gerbers | yes |
| net | Net name on the probe board. These net names may or may not be the same as the net name on the DUT. | yes |
| ref des | Reference designator on the probe PCB. | no, defaults to sequentially assigned by geographic position. |
| signal class | The height of a signal class can be set in the config file. Useful for setting the connection order of probes if hot plugging or looking for extra ESD protection. | no |
| routing class | Class for assigning connections. This is used to improve the routability by exchanging compatible signals. | no |
| net class | Net class for setting routing rules and trace dimensions. | no |
| imax | Peak current required. Used to check the probe tip selected is compatible. | no, if not included the check is skipped. This may be left blank with only the signals of interest given a value. |
| tip style | Probe tip style the socket will be populated with. | no, defaults to a crown type. Supply your own tips or select the required type at checkout. |
NOTE: If the same net is attached to multiple probes then only one routing class, net class, and imax can be set. If you want to make these nets not interchangeable then a different net name must be used to distinguish them.
Recommended Fields (but unused)
We don’t use these fields but we recommend you use them.
| Field(s) | Description | |
|---|---|---|
| source ref des | Useful to have available as a mapping and if using KiCAD then this and the pad number are used to pull out the probe placement and the net. | |
| source pad number | See above. | |
| pad style | Description of the test pad on the DUT. This will be used to choose the probe tip necessary. | |
| footprint | Footprint the test pad on the DUT if this is different from the pad style. | |
| engine connection | Requirements on the engine side to test this net. |