UCC28951: Topology selection

Sravan YESKURI

Prodigy 60 points

Part Number: UCC28951

Hi Team

My Design inputs:

input voltage range 1:- Vin min:316 Vdc, Vin nominal:587Vdc, Vin Max: 815Vdc

input voltage range 2:- Vin min:417 Vdc, Vin nominal:700Vdc, Vin Max: 1000Vdc

input voltage range 3:- Vin min:417Vdc, Vin nominal:800Vdc, Vin Max: 1200Vdc

output remains common for 3 diffrent input voltage range

Vout:48Vdc

Iout:13Adc

Pout:626W

Application:Fan power supply

Can you please suggest me which topology is Preferable and can I use PSFB full bridge for this wide range of input.

suggest me the best switching IC.

over 1 year ago

0 Mike O' over 1 year ago

TI__Guru* 86286 points

Hello,

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

Regards,

0 Mike O' over 1 year ago in reply to Mike O'

TI__Guru* 86286 points

Hello,

When it comes to designing any power supply it is recommended that you design for an input range of 3 to 1 max. This is because you can run into limitations with duty cycle. In your 3 different designs the input ranges are less than 3 to 1 so your designs are possible and the UCC28951 in a phase shifted full bridge (PSFB) should work for your design.

If you decide to move forwarded with this design the following link will bring you to an application note that discusses how to design PSFB using the UCC28951. I believe that you will find this application note useful in your design process.

https://www.ti.com/lit/pdf/slua560

Regards,

0 Sravan YESKURI over 1 year ago in reply to Mike O'

Prodigy 60 points

Hi Mike O'

Thank you for your reply, which topology is preferable for high efficiency and low cost & reliable for this wide range of input voltage.

Can you please suggest me the best Topology for isolated output.

0 Mike O' over 1 year ago in reply to Sravan YESKURI

TI__Guru* 86286 points

Hello,

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

Regards,

0 Mike O' over 1 year ago in reply to Mike O'

TI__Guru* 86286 points

Hello,

What efficiency target were you looking to achieve?

Regards,

0 Sravan YESKURI over 1 year ago in reply to Mike O'

Prodigy 60 points

90% Efficiency

0 Mike O' over 1 year ago in reply to Sravan YESKURI

TI__Guru* 86286 points

Hello,

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

Regards,

0 Mike O' over 1 year ago in reply to Mike O'

TI__Guru* 86286 points

Hello,

Typically to get greater than 90% efficiency requires SRs and ZVS to reduce losses.

Your power range is under 1000 W you could achieve this with an LLC. However, because your input range is more than 2 to 1 I would recommend against using this topology.

Since the UCC28951 in a full bridge can control SRs and has ZVS and can handle the input range of 3 to 1 which meets your design requirements. It is most likely the best and most economical choice for your design.

Regards,

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UCC28951: Topology selection