TPS23750EVM-107: TPS23750 output voltage ripple

Mason Noh

Expert 2490 points

Part Number: TPS23750EVM-107

Hi~ TI expert

I measured output voltage ripple of TPS23750EVM-107.

And there was too much ripple at no load condition.

and no change when adding a dummy resistor (120ohm).

It can be improve? or is it normal??

over 6 years ago

0 Thomas Amlee over 6 years ago

TI__Genius 9230 points

Hello Mason,

Could you tell me where & how they are measuring the ripple? The ground lead should be very short.

Thanks,
Thomas A.

0 Thomas Amlee over 6 years ago in reply to Thomas Amlee

TI__Genius 9230 points

Additionally, what output BOM are you using? Also, the measurement should be taken across the caps C11 or C12 on the EVM.

0 Mason Noh over 6 years ago in reply to Thomas Amlee

Expert 2490 points

Output option is 3.3V.

And we already measured across the caps C11 or C12 on the EVM.

Do you have another solution?

0 Thomas Amlee over 6 years ago in reply to Mason Noh

TI__Genius 9230 points

Hi Mason,

While I look for additional solutions, here are some resources that may be helpful:

Output Ripple Voltage for Buck Switching Regulator App Note: www.ti.com/.../slva630a.pdf
E2E Blog Post about Buck Output Voltage Ripple:
e2e.ti.com/.../2243.understanding-measuring-and-reducing-output-voltage-ripple

Best,
Thomas A.

0 Thomas Amlee over 6 years ago in reply to Thomas Amlee

TI__Genius 9230 points

Hello Mason,

Is the voltage spike present at full load (~1.3ohm)? To confirm, did you only just change R10 & R6 on the EVM for the 3.3V BOM? I will take a look at this in lab.

Thanks,
Thomas A.

0 Mason Noh over 6 years ago in reply to Thomas Amlee

Expert 2490 points

The voltage spike is present at light load (133ohm).

And I changed just R10 & R6 on the EVM for the 3.3V BOM.

Thanks to your support~

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TPS23750EVM-107: TPS23750 output voltage ripple