LM5122: 5.5kW Boost Design

Ken Yeap76

Expert 4565 points

Part Number: LM5122
Other Parts Discussed in Thread: LM5170

Need advice on below boost design.

Boost design with Po = 5500W . Vin =24V-46V and Vo=48V

Exploring if 6x of 48V@20A can be done with one LM5122 ?

What complexities we will run into in terms of driving more mosfets etc.

Thank you.

over 7 years ago

0 Youhao Xi over 7 years ago

TI__Guru* 78110 points

I think I already made an recommendation for this 5500W in an internal email earlier today: please look into the LM5170 instead for solution with fewer phases and better power sharing among multi phases.

The LM5122 driver is 3A limited. The number of FETs that can be driven without incurring much switching losses is determined by the total gate charge. Usually we would like not limit the FET turn-on and off times <100ns.

0 Youhao Xi over 7 years ago in reply to Youhao Xi

TI__Guru* 78110 points

Sorry for the typo: we would like TO limit the turn-on and off time...

0 user23874 over 7 years ago

Prodigy 10 points

Thank you Ken, will review this and get back soon.

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LM5122: 5.5kW Boost Design