Timeline for How does this control loop work?
Current License: CC BY-SA 4.0
10 events
| when toggle format | what | by | license | comment | |
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| Feb 11, 2021 at 21:27 | comment | added | Iron Maiden | That's fine, thank you very much. I'll keep trying some simulations to see what can be improved in the circuit. | |
| Feb 11, 2021 at 20:59 | comment | added | Iron Maiden | I can simulate anytime needed, I've been trying to get this done in LTspice actually, because I don't have any PCB at the moment. My load is the one in LTspice, I have no real circuit. I have just changed to 3.3K and I got 43.35V @ steady state in roughly 580ms. | |
| Feb 11, 2021 at 20:47 | comment | added | Iron Maiden | So maybe my circuit is not working in DCM like his? That's something I hadn't thought about to be honest. Yet I still don't understand how my circuit could not follow the idea presented by maxim's document. | |
| Feb 11, 2021 at 20:44 | comment | added | Iron Maiden | I have changed R1 to 1k and now the output voltage reaches a steady state value of 40V in 240ms | |
| Feb 11, 2021 at 20:32 | comment | added | Math Keeps Me Busy | OK. I think I know what is going on. In the video, he demonstrates a falling voltage when (what looks like) a 1/4 watt resistor is added as a load. From this, I conclude that the boost converter is operating in discontinuous conduction mode (DCM). The control mechanism is different in DCM than in CCM, DCM is entered when the load is "light", in relation to the L (and C?) of the converter. In your schematic, you have a 50\$\Omega\$ R1, What happens when the load resistance is increased, to say 1K? What is your output voltage then? | |
| Feb 11, 2021 at 20:10 | comment | added | Iron Maiden | Moreover, I have just updated the additional information about the circuit. | |
| Feb 11, 2021 at 20:09 | comment | added | Iron Maiden | It's exactly this stable point very near the designed output voltage that my circuit is not being able to converge, and I've assembled the circuit just like it was done in maxim's website. For me it's weird because if there is not an integrator taking part of the control loop, I don't see how the circuit will actually converge, although there's lots of explanations of this mode on the internet. | |
| Feb 11, 2021 at 13:22 | history | edited | Math Keeps Me Busy | CC BY-SA 4.0 |
expanded answer
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| Feb 10, 2021 at 19:39 | history | edited | Math Keeps Me Busy | CC BY-SA 4.0 |
added 29 characters in body
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| Feb 10, 2021 at 19:32 | history | answered | Math Keeps Me Busy | CC BY-SA 4.0 |