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Hi, AN57, basically puts forward that there is a limit to the amount of output capacitance that a topswitch flyback can have (it says res freq should be >500Hz). Why is this? Surely if compensated for, then any amount of output capacitance is OK.?

Hi, In AN57, it is said the Q should be taken as 0.15 to 0.3...but i calculate Q from TN-203 (microsemi) page 8, and its nowhere near that. Are you sure this Q is correct?

Hi, We are doing FSGM0565 replacement with TOP255GN...however, i am forced to use transformer with np/ns = 84/19 and so its in CCM at low mains (its 90-265vac). Its 24v, 0.8a. The feedback loop calc from AN57 is giving nonsense figures. Also, AN57 says Q should be taken as 0.15....but

Hi, Please respond, as we wish to do high volume flyback liek the attached, it is for FSGM0565 replacement... So....................... Please advise how to prove stability for the attached TOPswitch-HX (TOP255GN) Flyback which operates in Continuous Conduction Mode? It is with 90VAC input and 24V, 0.8A output. I calculated the

Hi, I did the attached TOPswitch-HX Flyback design in PI Expert. I then used the equations given by Power Integrations in AN-57 to calculate the crossover frequency, gain and phase margins. However, the equations given in AN-57 give nonsense Bode Plots (as attached in Excel). The AN-57 feedback equations give

Hi, What is the planar transformer creepage distance between primary turns and secondary pins for reinforced insulation? Best regards,

Hello, I get a pcb with an Inn2023K back. As error description I only get, it stops working. I test it at my desk and it looks like the primary 5,95V regulator doesn't work anymore. Also the Bypass pin has a resistance to ground by 2Ohm. On the pcb are

Hi, AN-57 is , as you know, a Power Integration App Note. Top RHS of page 6 of AN57 says the resonant frequency between c(out) of the flyback, and the "effective L(sec)" should be <500Hz. This stipuation has never before occurred for any flyback converter, in any text or book

According to the datasheet of many devices, spark gap is supposed to be placed across one AC input and the positive output rail. I've seen two spark gaps used on top and bottom side of certain reference designs. How these are connected, and when you have a dual output design

Hello, I was wondering if the INN3672C-H602 device used in the design example RDR-611 (attached) is supported in the PI Expert utility. How can I modify this design to use different outputs? Thanks