LM5116: Spike pulse issue of LM5116

user5973782

Part Number: LM5116

Hi,

I use the LM5116 in our DC/DC design, the input voltage is 9-92V, output voltage is 5V, output current is 0.2A, inductance is 65uH, the switching frequency is 150KHz, we check the voltage of inductance with

oscilloscope(picture 1), there are the noise interfrence in the chopper switch(picture 2 & 3), we use the design the same as the reference in the datahsheet, can you help to check the oscillogram and advise

your comment for this issue.

over 6 years ago

0 Samuel Jaffe over 6 years ago

TI__Mastermind 25590 points

User,

Please share the full schematic and the full layout.

Are you using the tip and barrel method to measure VOUT? Sometimes the measurement technique shows noise that isn't really there so it's important to use the tip and barrel method.

-Sam

0 user5973782 over 6 years ago in reply to Samuel Jaffe

Prodigy 70 points

Hi Samuel,

Thanks for your quickly reply.

Yes, we use the tip and barrel method to measure the ripple circuit and the schematic and layout for your evaluating.

0 Samuel Jaffe over 6 years ago in reply to user5973782

TI__Mastermind 25590 points

User,

Please provide the full layout. I'm not finding the LM5116 on the layout you provided. Please also share all layers.

-Sam

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LM5116: Spike pulse issue of LM5116