UC3825BN driving mosfets of push pull converter

[abhinand rd]

Hello
I am using uc3825bn for driving mosfets of push pull converter. When I tried and tested (on bread board) the open loop configuration given in the datasheet, I got perfect outputs on the pins 11 and 14 with desired dead time between them. But on many occasions the outputs on this pins weren’t stable the disappeared without any reason. Also I used polyester capacitors rather than ceramic since they have steady capacitance. And when I interfaced it to power circuit the all the waveforms were distorted including the PWM pulses from pins 11 and 14. Can anybody help me in this regard as what needs to be done?
Thank you.

 

[Orson Cart]

looks like you have interference problems - can you post a photo of your layout and a full schematic?

 

[abhinand rd]

hello
i have used the figure 14 circuit(uc3825a datasheet) for generating pwm pulses . and my power circuit is similar to the figure 1(a) in another attachment.
thank you.

 

[Orson Cart]

Yes - interference and layout problems....

 

[abhinand rd]

can u please suggest how do i overcome interference problems?

 

[Orson Cart]

first you need to post your ACTUAL schematic and photo's of your ACTUAL layout...so the problems can be seen.