LM25085: LM25085

brg barg

Prodigy 35 points

Part Number: LM25085

Hello,

We need your advice for selecting a High side switch buck converter ic with similar functional as LM25085.

Requirements are: vin 8 to 20v+-, Vout 6v, 4A and lowest frequency posiible.

Thank you in advance

over 2 years ago

+1 Henry Kou over 2 years ago

TI__Expert 3766 points

Hi,

This quickstart spreadsheet attached will allow you to form a solution with your design parameters. In addition, TI's buck converter filtering site will allow you to narrow down similar parts. For EMC mitigation I highly recommend you take a look at the following input filter app notes and consider buck converters with spread spectrum and more optimized for low EMC.

Regards,

Henry

Quickstart calculator: https://www.ti.com/tool/LM25085-5085QUICK-CALC

Filtering strategies: https://www.ti.com/power-management/non-isolated-dc-dc-switching-regulators/engineers-guide-low-emi-dcdc-regulators.html?keyMatch=EMI

https://www.ti.com/power-management/non-isolated-dc-dc-switching-regulators/engineers-guide-low-emi-dcdc-regulators.html?keyMatch=EMI

https://www.ti.com/power-management/non-isolated-dc-dc-switching-regulators/step-down-buck/products.html

0 brg barg over 2 years ago in reply to Henry Kou

Prodigy 35 points

Hi Henry,

Regarding using lm25085 that feeds from a 12v battery, in the data sheet p#24, its reccommended to add a bulk capacitor parallel& priore Cin if distance is more than a few inches. Can you please check and advice if a 100uf is enough? if not, can you reccomend other value?

Details are: Vin 8-16v, vout 6v, Iout=5A.

Thank you

0 Henry Kou over 2 years ago in reply to brg barg

TI__Expert 3766 points

Hi,

It is good practice to include the CBulk to handle input transients among other things and the amount varies by design. I recommend reading through the following resources to help you choose the best CBulk for your application.

https://www.ti.com/lit/pdf/slyt670

https://www.ti.com/lit/pdf/slta055

Regards,

Henry

0 brg barg over 2 years ago in reply to Henry Kou

Prodigy 35 points

Thank you

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LM25085: LM25085