LM5155-Q1: buck-boost mode in flyback

Roy Chou1

Genius 13405 points

Part Number: LM5155-Q1
Other Parts Discussed in Thread: LM5155, UCC24612, PMP22151, PMP40569

Hi Team,

My customer is finding the isolated DC/DC solution and below is the spec.

Vin = 13V-36V (nominal = 24V)

Vout = 24V

Iout = 4A

I find that LM5155-Q1 could meet their requirement. Do you have any more appropriate solution?

Thank you for your support.

Regards,

Roy

over 4 years ago

0 Garrett Roecker over 4 years ago

TI__Mastermind 21720 points

Hi Roy,

Thanks for reaching out with your questions and for considering the LM5155 in your design

For a flyback converter 100W is achievable but will need to ensure the output diode isn't too hot at full load. To work around this the UCC24612 can used to make the flyback a synchronous topology as shown in PMP40569. A good staring point for this design is PMP22151.

Please let me know if you have any questions.

Thanks,

Garret

0 Roy Chou1 over 4 years ago in reply to Garrett Roecker

TI__Genius 13405 points

Hi Garrett,

Thank you for your comments. In addition, the customer would concern the efficiency of light load, do we have more appropriate solution?

Regards,

Roy

0 Garrett Roecker over 4 years ago in reply to Roy Chou1

TI__Mastermind 21720 points

Roy,

What is the efficiency requirement and the load current it should occur at?

Please contact me directly and we can have a more in depth discussion.

Thanks,

Garrett

Power management

Power management forum

LM5155-Q1: buck-boost mode in flyback