How to make a simple Pogo pin test fixture for PCB probe testing
Video
To test the SAM15x15 board automatically, I made the tool described here. As you can see, the mechanical construction is very simple.
There are two identical test PCBs used, with 1.05mm holes for the spring-loaded test probes. With the test program, the SAMD21 can test itself for short-circuits between pins and open solder connections.
Circuit
The pins are made low one by one, so that the LEDs lights up. By measuring the LED current with R35 and the ADC on pin1, it is possible to determine whether the SAMD21 pins are working correctly and if there are short circuits or open connections.
Test sketch
The test sketch is available on GitHub.
Program and test procedure
Install the SAM15x15 package
http://www.avdweb.nl/arduino/samd21/sam-15x15-installation.html
Connect the programmer
Connect it to the 5pin JST connector.
I used this DIY programmer but you can also use an Atmel programmer:
http://www.avdweb.nl/arduino/samd21/samd21-programmer.html
1. Burn the Arduino Zero bootloader
Insert a SAM15x15 board.
Burn the bootloader by using the programmer.
Repeat this for all SAM15x15 boards.
Attention
- If the spring force of the probes is insufficient, the holding plates must be turned clockwise.
- Some I/O pins will be blown up when the SAM15x15 is placed incorrectly.
2. Download the test-sketch
Use the Arduino IDE and connect an USB cable to the test fixture.
Insert a SAM15x15 board with the Arduino Zero bootloader already burned, see first step.
See the video how to do.
Repeat this for all SAM15x15 boards.
Links