5. [Fixed] Analog output: Unstable output voltage

[Fixed] Analog output: Unstable output voltage

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    Just want to share my experience with the analog output:
    I had mine external powered (AOV and AOG). The voltage was about 16V. I thought it was stable enough (15.94V ~ 16.30V) but I was not able to get the output AO stable. The output voltage was flapping between 2V to 9V with Analog Output 1 set to 5 (evok api).

    My first guess was a CPU which was not able to handle the PWM. However, the evok api was build by the Unipi guys, so I couldn't believe that was the issue.

    Then I found this brand new wiki: http://unipi.technology/wiki/Using_Analog_Output. I wired AOV to 12V (orange connector) and A0G to AI1- (which is internally connected to GND). Check the wiki for wiring schema. I checked the 12V output and was surprised how stable it was! That output was 12.17V stable. Then I measured the output AOV / AOG with Analog Output 1 set to 7. After adjusting the board trimmer, the Analog Output works as expected!

    Extra bonus:

    • No need for external power (12V)
    • Output is also measured using AI1+, so I can check if the voltage is still as expected.

    Hope this helps!

    0
  • E

    Just want to share my experience with the analog output:
    I had mine external powered (AOV and AOG). The voltage was about 16V. I thought it was stable enough (15.94V ~ 16.30V) but I was not able to get the output AO stable. The output voltage was flapping between 2V to 9V with Analog Output 1 set to 5 (evok api).

    My first guess was a CPU which was not able to handle the PWM. However, the evok api was build by the Unipi guys, so I couldn't believe that was the issue.

    Then I found this brand new wiki: http://unipi.technology/wiki/Using_Analog_Output. I wired AOV to 12V (orange connector) and A0G to AI1- (which is internally connected to GND). Check the wiki for wiring schema. I checked the 12V output and was surprised how stable it was! That output was 12.17V stable. Then I measured the output AOV / AOG with Analog Output 1 set to 7. After adjusting the board trimmer, the Analog Output works as expected!

    Extra bonus:

    • No need for external power (12V)
    • Output is also measured using AI1+, so I can check if the voltage is still as expected.

    Hope this helps!

    0