LP8866-Q1: EMI

Chen Ching Yi

Part Number: LP8866-Q1

Hi Expert:

I have two questions regarding the LP8866-Q1 SNVA964 Application note.

The first question is whether the Figure 7 (b) on page 5 depicts the spread spectrum disabled or spread spectrum enabled with ±3.3% variation?

The second question is, why in (b), the switch frequency harmonics measured values for peak and average at 1.2MHz are the same?

Typically, even with spread spectrum disabled, the average value should be lower than the peak value. Do you have the raw data for this?

Thank you.

0 Zhiqian Wu 11 months ago

Hi, Ching yi

I think there is a typo here, the figure 7(c) is for 3.3% variation and the figure 7(b) is for disable.

0 Chen Ching Yi 11 months ago in reply to Zhiqian Wu

Hi Zhiqian,

Thanks for your reply question 1

How about question 2 ?

The second question is, why in (b), the switch frequency harmonics measured values for peak and average at 1.2MHz are the same?

Typically, even with spread spectrum disabled, the average value should be lower than the peak value. Do you have the raw data for this?

Thank you.

0 Zhiqian Wu 11 months ago in reply to Chen Ching Yi

Hi, Chingyi

If you zoom in, the peak value is still higher than average value.

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