TPS7H5005-SEP: Flyback Converter

Hello,

The engineer who covers this device is out of office today. They will be back tomorrow and can provide their feedback or follow-up questions when they return.

Thanks,

Sarah

Hey Hridya,

Can you clarify what the question is?

Thanks,
Daniel

We are designing a flyback converter with 4 secondary windings. In this case how should we find the primary current? Since only one output voltage is regulated.

Hey Hridya,

You find the primary current by imputing the current as if all secondary windings are also coming from the regulated winding.

For example lets say there is a 15 V/ 1 A winding and a 5 V / 2 A winding.
This has the same wattage as a 5 V/ 5 A output thus you would put 5 A.

Thanks,
Daniel

Hello Daniel,

I was checking for the input current requirement in case of 4 secondary winding. My issue is whether i should consider only 15V, 1A regulated as mentioned in the excel snip, or whether i should calculate considering my efficiency 80%. In first case my primary peak current is 1.5A and second case, it is coming around 3A. This current value is crucial since we need to select the Magnetics for the same.

The four secondary windings details are 

1) 15V-1A (Regulated)

2) 12V-2.5A

3) 5V-0.5A

4) 5V-0.5A

The flyback is designed for 50W and efficiency is 80% considered.

Ok

Welcome.

Thanks,
Daniel