Step Down Converter solution for Industrial application

Adrian Ymeraj

Other Parts Discussed in Thread: TPS54560, LM5145, TPS40200, LM5176, LM5085

Hello team,

We have a device that works at 24Vdc and 3A, this is powered by an 18/36 Vac or 24 Vdc source, so we would need a step-down with a 100% duty and I think also a P-channel mosfet is needed.
Because of the voltage drops on the cables it can sometimes happen that the 24 Vdc become 22V, in this case the dc / dc passes everything (minus the DV on the mosfet) or it creates some problem?
This is because I have to control a valve that accepts 22Vdc as the minimum voltage.

Could you please share your thoughts or any suggestions?

Thank you and best regards,

Adrian

over 5 years ago

0 Adrian Ymeraj over 5 years ago

TI__Expert 3810 points

Just as an example I was look to find alternatives to the LTC3864

Like the TPS40200, TPS54560, LM5145. Do you have any suggestions?

Thank you and best regards,

Adrian

0 Jasper Li over 5 years ago

TI__Mastermind 46905 points

Hi Adrian,

it seem the input voltage could be lower or higher than VOUT. so I would suggest a buck-boost device, such as LM5176.

0 Adrian Ymeraj over 5 years ago in reply to Jasper Li

TI__Expert 3810 points

Jasper,

yes In reality, when the voltage drops below 24 it must do only as a bypass introducing the least possible voltage drop. Also, I asked to the customer and due to cost and size they can't afford to use a buck-boost.

Thus another question is: given the LM5085 which is a 100% duty cycle, I would like to know if with a Vin=22V you can get a Vout of 22V minus the voltage drop on the MOSFET.

Thank you and best regards,

Adrian

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Step Down Converter solution for Industrial application