High ripple voltage during relay switching with LNK3205

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I designed a AC/DC with a LNK3205

This regulator generate a voltage 12VDC. It supplies a DCDC to generate 3,3V for a microcontroller and a relays.
Every thing works correctly but I have an issue durin the relays switching : there is an high ripple during the switching.
The current consumption is about 90mA

Added file show schematics and ripple.

I don't find the reason of this ripple.
Can I have some help ?

Best regards

첨부 파일Size
Schematics50.23 KB
ripple32.22 KB


Thank you for using power integrations product.
To help you with your concern,
Is it possible for you to provide the schematic in which the relay connection is clear?
Since you are using a DCDC to generate the 3.3V for your application,
can you please verify if the problem is really on the power stage. Have you tried
isolating the power stage by using an external bench DC power supply and
verify the ripple during relay switching?

Is it possible for you to provide switching waveform of the power stage during the relay switching on or off. Thanks