oresat-solar-hardware/1u_panel/test-plan.md

1U Panel Test Plan

This assumes a completely assembled board, with a detailed visual inspection done that removes all visible shorts and corrects for any visually bad solder joints.

This testing assumes R24-R27 (CAN bus addresses) are not stuffed.

Equipment

• Two channel power supply with constant current limit
• DMM
• Scope (50 MHz or better)
• SWD programmer for the STM32F091 (a debug cable, a Card Debug Board v2, and a laptop that can compile and program OreSat firmware).
• Two solar cell test panel with halogen bulb (or solar simulator).
• OreSat battery card (or any 2S Li ion battery pack) that is around 7.2 V, and definitely between 6.0 V and < 8.0 V.
• JouleScope with JouleScope software
• Temperature controlled hot air gun.

Test Plan

In the following tests, do not continue to test if a test fails. Instead, debug the PCB then continue to test. If you don't fix these problems in order, you may end up destroying other circuits.

1. Circuit Test: Power

   1. Set: 5V @ 50 mA max into Vsolar.
   2. Measure: Solar module is drawing 13.5 +3/-1 mA.
      • Debugging notes: If the current draw is 50 mA, you have a short. Removing R17, R14, and R20 will let you identify where the short is. Hunt down the short in the downstream circuits using these three resistors. If the current draw is low, more debugging is necessary to determine the source of the error. 1.Measure: 4.7V +/- 0.1V at TP12.
      • Debugging: The LT1618 should be off, so you'll just see the drop of D5. The LTC4412 may not work at 5V, so it's OK if TP14 is weird.
   3. Measure: 3.3V +/- 5% at TP6. (TODO: ACTUAL PERCENTAGE ERROR)
      • That TPS63030 is notoriously hard to reflow, so if that's not working, probably reflow that IC or pull it and retry.
   4. Set: insert RBF jumper into J1.
   5. Measure: TP6 should drop to near 0 V.
      • Debugging notes: This verifies the !SD circuit is working on the 3.3V supply.
   6. Set: Remove RBF jumper.
   7. Set: Pull TP10 up to 3.3V @ 10 mA max.
   8. Measure: 8.4V +1%/-10% at TP12.
      • Debugging notes: The current limit on the LT1618 is set to very low, so it might current limit if there's any issue down the line towards Vbus.
   9. Measure: 8.4 V +1%/-10% at TP14.
   10. Set: Insert RBF jumper into J1 and put some load to ground from TP14 (about 10k).
   11. Measure: ~ 0 V on TP14.
       • Debugging notes: This verifies the !SD circuit is working on MPPT / 8.2V supply.
   12. Set: Remove RBF jumper.
   13. Set: remove power from TP10.

2. Program microcontroller

   1. Set: 5V @ 50 mA max into Vsolar.
   2. Set: Make sure UART debugging is enable in firmware (TODO: HOW?!)
   3. Set: Program microcontroller using the SWD programmer.
      • Debugging Notes: make sure to do make clean && make all at least once before make write.
   4. Measure: LED D6 should be blinking.
   5. Measure: Reboot the microcontroller using the reset switch on the Card Debug board and look for serial console boot up message.

3. Functional Test: MPPT

   1. Set: hookup two cell test panel to Vsolar.
   2. Set: Turn on some amount of irradiance on the cell test panel to give it plenty of power to run, like 25% of 1 sun.
   3. Set: hook up battery pack to Vbus (or TP14) through JouleScope and run JouleScope software.
   4. Measure: some amount of power flowing into the battery pack when irradiance is reasonable.
   5. Set: Make irradiance go up and down.
   6. Measure: see amount of power flowing into the battery pack track the irradiance level.

4. Functional Test: Temperature

   1. Set: same setup as in (3) above.
   2. Measure: on serial debug output, temperature on both TMP101A is around room temperature (~ 25 C).
   3. Set: Adjust hot air gun down to ~ 100 C and apply hot air to each TMP101A.
   4. Measure: see the temperature on each TMP101A go up to ~ 100 C.