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Dear all I need to make a full bridge smps with symmetrical outputs of + 200V and -200V and both outputs have to be regulated. The projects I have found regulate only on the positive side and my application requires regulation on both sides. Can anyone suggest a circuit for this...

hi all in continuation of my saga, i checke that i made a mistake in calculation of inductor. the correct value is 100uH (checked in software calculator of Wurth electronics). but the problem persists. i made a inductor with core EE25 with 10 turns of wire and i manually have changed the gap...

Hello all thanks for the answers. you are right, i forgot to put the current sense resistor in the pin 3. In my board it exists, but not in schematic. my board is a prototype, not a final layout. i removed the C30 and i search in the web about slope compensation, here is my new schematic...

hi there i noted that exists a noise in the oscillator when the mosfet waveform becames wrong. With a 10R gate resistor, the waveform became worst. With a 68R resistor, the problem surges with inputs of 11~8 Vcc. i noted a problem: in the next pictures, exists a peak current after the pulse of...

Hi there thanks for the answer. I have tried with Rg with 10R and 22R, with 47R, when the input is above 14V, the wave form is good, like the last picture. I put a diode in parallel to Rg, but it doesn´t resolve the problem. the IC supply and oscillator are ok, the pcb board is a prototype...

Hello all I made a sepic converter with UC3843. But i had problems with the regulation and current behavior in the mosfet. the input is 10 ~25V and output is 14V 0,8A. When the input is above 14V, the current in mosfet is good, but under 14V, the current is not correct, like the attached...

Hi there! i´m having problems to stabilize a feedback for smps full bridge 1200 W. here is the schematic attached. i´m using the uc3524 and optocoupler. i tried many values of R and C in TL431 and in the compensation of ic controller, but without sucess. anybody can help me? tks Marcelo

Hello all.. i´m working in a smps flyback 138W DCM input: 80 - 250 Vac, output 13,8V x 10 A. the schematic is this: it´s working, but when i apply load (about 4 A) the leakage voltage across the mosfet is very high... look: . the transformer is 42/15 core, prim 11 + 11 turns, secondary 3...