Timeline for Multiple output Flyback - Stacked transformer - Cross regulation - TL431
Current License: CC BY-SA 4.0
11 events
when toggle format | what | by | license | comment | |
---|---|---|---|---|---|
Jun 22, 2020 at 13:41 | history | bounty ended | Jess | ||
Jun 19, 2020 at 19:58 | comment | added | Jess | I think there is an other equation to take into account ! | |
Jun 19, 2020 at 19:55 | vote | accept | Jess | ||
Jun 19, 2020 at 19:51 | comment | added | Jess | I appreciate all your effort for answering the question but I do not understand why the outputs will reach 5V and 12V because you decide to apply a coefficient equal to 0.6 and 0.4. Why the physics should apply your coefficients ? The physics could stabilize one output at 0V, no current will flow through your resistor and the other output will go up in order to make flowing enough current trough your resistor and set the reference to 2V5. And the controller will have no reason to change its duty cycle as the reference is at 2V5 | |
Jun 19, 2020 at 10:46 | comment | added | Rohat Kılıç | @Jess see my edit then. | |
Jun 19, 2020 at 10:46 | history | edited | Rohat Kılıç | CC BY-SA 4.0 |
added 3180 characters in body
|
Jun 17, 2020 at 9:30 | comment | added | Jess | Thank you I got the idea. Nevertheless you have one equation and to unkown outputs Vout1 and Vout2. I do not know how you can find Vout1 and Vout2 so. The two outputs are linked together. Obviously it miss something ... Otherwise I could say Vout1 = 0V and Vout2 = X in order to have the reference voltage equal to 2V5. | |
Jun 17, 2020 at 1:13 | comment | added | Rohat Kılıç | @Jess I'm on mobile, so I cannot show any mathematical details. But you can do it by yourself: The REF pin voltage is 2.5VDC. Assumming the pin bias current is zero, the current that flows through R6 is 2.5/R6=(Vo1-2.5)/R5+(Vo2-2.5)/R7. To solve this, you should define an "importance factor" for each output and the sum of the factors should be 1. For example, if you want Vo1 to be regulated more tightly then the current that flows through R5 should be greater than the other, so its imp factor should be greater (e.g. 0.7 for Vo1, 0.3 for Vo2). I'm sure that you got the idea. The rest is simple. | |
Jun 16, 2020 at 20:12 | comment | added | Jess | You re right ! The voltage drop across the diode depends on the load. In any case what would be Vout1 and Vout2 in the case of this kind of feedback. If you can show some maths it would be nice to you. | |
Jun 16, 2020 at 19:56 | history | edited | Rohat Kılıç | CC BY-SA 4.0 |
added 30 characters in body
|
Jun 16, 2020 at 19:51 | history | answered | Rohat Kılıç | CC BY-SA 4.0 |