TPS62933O: SW frequency on light load and no load

Amber Si

Part Number: TPS62933O

Tool/software:

Hi team,

My customer want use TPS62933O(VIN 24V, VOUT 5.5V) which has OOA feature, datasheet specify SW frequency can always be >=30kHz.

But my customer test when device is in no load or light load(50mA), the SW frequency will drop in around 20kHZ as below SW waveform, is that normal? or How we can increase frequency on no load?

Amber

3 months ago

0 Alla Ushasri 3 months ago

TI__Expert 3400 points

Hi Amber,

I can observe that measurement of frequency through SW node is not correct, ask them to measure the frequency through Inductor current.

Best regards,

Usha.

0 Amber Si 3 months ago in reply to Alla Ushasri

TI__Intellectual 2305 points

Hi Usha，

yellow waveform is inductor current

Is that correct？not sure the frequency from inductor current is 15k or 29.7khz？

0 Alla Ushasri 3 months ago in reply to Amber Si

TI__Expert 3400 points

Hi Amber,

Yeah, it is correct, so the frequency is nearly around 30kHz.

Best regards,

Usha.

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TPS62933O: SW frequency on light load and no load