LM5039: Application circuit using LM5039

Conor

Part Number: LM5039

Tool/software:

Hi,

I have experience using LM5039 to control a push-pull converter. Is it possible to use one LM5039 to operate two single-ended forward converters?

Thanks,

Conor

over 1 year ago

0 Steven Mappus1 over 1 year ago

TI__Mastermind 32205 points

Yes

0 Conor over 1 year ago in reply to Steven Mappus1

Guru 11690 points

Are there any example circuits or reference documents for the above?

0 Steven Mappus1 over 1 year ago in reply to Conor

TI__Mastermind 32205 points

Conor,

LM5039 has an asymmetrical output where each duty cycle is D up to Dmax=50% (less in practice and more like 45%). You cannot control the duty cycle of each output independently, if this is your intent. Likely we will not find a refence design example for such a use case but you can always search the TI Reference Design database here.

Regards,

Steve

0 Conor over 1 year ago in reply to Steven Mappus1

Guru 11690 points

Hi Steve,

I understand that the LM5039 cannot be controlled independently.

I also searched the database, but could not find any actual reference circuits. There is no detailed documentation on how to connect and control the LM5039 HO/LO to separate converter FETs, so I don't know how to design it. Any advice would be greatly appreciated.

Thanks,

Conor

0 Steven Mappus1 over 1 year ago in reply to Conor

TI__Mastermind 32205 points

Conor,

You are proposing to use the controller in a way it was not intended. This is why you will not find any guidance or reference design examples. There are many issues that must be overcome with your proposed LM5039 use but that's not to say it can't be made to work by designing external circuits. You have not stated what you are ultimately trying to accomplish so I am unable to make a good suggestion.

"one LM5039 to operate two single-ended forward converters?"

Regards,

Steve

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LM5039: Application circuit using LM5039