UC3846: Selection of RT & CT values for UC3846

Grishma Tathe

Part Number: UC3846
Other Parts Discussed in Thread: LM5045

Hi Team,

I am working on the IC UC3846 to design the push-pull converter. Please help with the below queries:

1. Could you please guide me in selecting the RT & CT values for the 100kHz Oscillator frequency?

2. For how much voltage & power rating this IC can be used to design a Push-pull converter?

Thanks & Regards,

Grishma Tathe

0 Sean Xu over 1 year ago

Hello,

With RT=10k, CT=4.7 nF,- Fsw = 43kHz. By using the formula Fsw = 2.2/Rt*Ct, Fsw is 100kHz when CT = 2.2nF.

Max voltage is 40V on Pin 15, maybe max power is around 200W. It really depends on power stage design.

0 Grishma Tathe over 1 year ago in reply to Sean Xu

Hello,

Thank you for your response.

Regarding the second question, the output power rating of the push-pull converter is 190V, 2700W. Can I use UC3846 IC for this application?

Grishma

0 Sean Xu over 1 year ago in reply to Grishma Tathe

I would like to recommend to use LM5045, full bridge converter to output 2700W.

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