UCC24624: Can it be used for phase shifted full bridge topology?

Part Number: UCC24624
Other Parts Discussed in Thread: UCC28951, UCC28950, UCC256402

Hi. Can I use this part to implement soft switching in secondary synchronous rectifier configured in current doubler configuration in phase shifted full bridge topology? If not then is there any TI SR controller optimized for PFSB and current doubler configuration?

Thanks.

Shashank

over 2 years ago

0 Manikanta Pallantla over 2 years ago

TI__Genius 16155 points

Hi Shashank,

I have assigned this thread to the PSFB expert. He is currently out of office. He will respond to you tomorrow.

Regards

Manikanta P

0 Mike O' over 2 years ago in reply to Manikanta Pallantla

TI__Guru* 86266 points

Hello,

I am reviewing your inquiry and will get back to you shortly.

Regards,

0 Mike O' over 2 years ago in reply to Mike O'

TI__Guru* 86266 points

Hello Shashank,

The UCC24624 was designed for flyback converters and LLC. I would not recommend it for a phase shifted full bridge converter.

You could use the UCC28951 phase shift full bridge controllers that have outputs to control FET drivers to drive the SRs.

The following link will get you to the UCC28951 product folder where you will find the data sheet, application note and design tools.

https://www.ti.com/product/UCC28950?keyMatch=UCC28950&tisearch=search-everything&usecase=GPN-ALT

Regards,

Mike O

0 SS over 2 years ago in reply to Mike O'

Prodigy 75 points

Hi Mike. Thanks for your reply. I tried to read through the datasheet of UCC28951. I am trying to understand if the controller is able to achieve soft switching - ZVS or ZCS in the secondary synchronous rectifier MOSFET.

Are you able to help me with some information on this please?

Thanks,

Shashank

0 Mike O' over 2 years ago in reply to SS

TI__Guru* 86266 points

Hello,

I am reviewing your inquiry and will get back to you shortly.

Regards,

0 Mike O' over 2 years ago in reply to Mike O'

TI__Guru* 86266 points

Hello,

The phase shifted full bridge converter can achieve ZVS on the primary. The topology does not utilize ZCS.

Regards,

0 SS over 2 years ago in reply to Mike O'

Prodigy 75 points

Yes. However, my question is - Can it achieve any form of soft switching on the secondary MOSFETs? For example, it will only switch the secondary MOSFETs after the body diode conducts so that the voltage across the MOSFET is minimum before it switches.

+1 Mike O' over 2 years ago in reply to SS

TI__Guru* 86266 points

Hello,

The UCC28950 was designed for ZVS on the primary of a PSFB and hard switching on the secondary.

Designing an LLC (UCC256402) will give you ZVS on the primary and ZCS on the secondary at resonance.

Regards,

Power management

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UCC24624: Can it be used for phase shifted full bridge topology?