24V to 24V design.

Marc Figliuolo

Prodigy 100 points

Other Parts Discussed in Thread: TPS54260, LMR33620, LM3409HV

Hello

I need to design a dcdc power supply with mainly four operation modes:

1. Vin 48V -> Vout 24V

2. Vin 48V -> Vout 24V..12V (adjustable)

3. Vin 24V -> Vout 24V

4. Vin 24V -> Vout 24V..12V (adjustable)

In all modes Iout ranges from 50mA to 2A.

I have no problem with the 48V operation and the adjustable output. (TPS54260)

Can you propose me the buck chip which can produce an outputvoltage as close as possible to the input voltage?

The aim is to produce an output voltage as close as possible to the 24V input.

Is there a design where I can switch the input directly to the output without regulation?

Thanks, greets Marc

over 5 years ago

0 Samuel Jaffe over 5 years ago

TI__Mastermind 25590 points

Marc,

You can use the LMR33620 for a 36V rated 2A output. This part has dropout frequency foldback. It reduces the switching frequency in dropout conditions to increase the effective duty cycle. If you need better performance consider adding a load switch from the input to the output.

-Sam

0 Samuel Jaffe over 5 years ago in reply to Samuel Jaffe

TI__Mastermind 25590 points

Marc,

I see you've clicked that my response did not resolve your issue. Please let me know what further questions you have regarding your initial question.

Thank you,

-Sam

0 Marc Figliuolo over 5 years ago in reply to Samuel Jaffe

Prodigy 100 points

Sam,

Yes this is correct.

The regulator you proposed is rated for use with Vin max 36V, but I need 48V.

The actual solution of our design is to do this with a Loadswitch.

The question is:

Is there a chip where its possible to swich the input directly to the output without regulation (an integrated solution)?

Thank you

GreetsMarc

0 Samuel Jaffe over 5 years ago in reply to Marc Figliuolo

TI__Mastermind 25590 points

Marc,

We have the LM3409HV which is a 70V rated PFET buck controller (external FETs) which operates at 100% duty cycle during dropout conditions. Does this satisfy your conditions?

-Sam

Power management

Power management forum

24V to 24V design.