LM5001: LM5001 Vout problem

Hi,

Using the alligator clip GND wire of your oscilloscope probe forms a nice loop antenna will pick up radiated noise.

It's suggested to measure directly across the output capacitor when measuring the output voltage ripple. You can remove the ground clip lead on the probe and measure right across the capacitor. A better way to measure is to use a wrapped ground wire around the barrel of the scope probe. This will greatly reduce the noise pickup.

You can look at this blog to know the details of how to measure the output voltage ripple: e2e.ti.com/.../2243.understanding-measuring-and-reducing-output-voltage-ripple

Best Regards,
Zack

Dear Zack
We have the test method according to TI's requirements，our test method is no problem. Can you help to check the if there a problem with the schematic? For Switching frequency，resistance ratio?

Hi,
The frequency in this schematic is 680kHz?
These noise comes from the switch node. You can add some 1uF ceramic capacitors to absorb high frequency noise or change the RCD circuit parameters to decrease SW spikes.

Dear Zack
Thank you~