LNK306DGTL Audible noise issue
Posted by: Arun
on
Hi,
We are using the LNK306DGTL in our project to generate a 5V, 250mA output and using this power to drive relays and microcontroller
During prototype testing, we observed audible noise coming from the power circuitry.
I’ve attached the schematic for your reference.
Could you please review it and let us know if any component changes are needed to eliminate the noise?
Thanks in advance for your support.
Files
LNK306-5V.png
(31.07 KB)
Hi Arun,
Good day. Thank you for choosing Power Integrations.
You can try adding a series resistor connected with your feedback capacitor (C2) to eliminate the audible noise, similar to the example shown in the attached photo below (C4 - feedback capacitor, R5 - series resistor). We also recommend that you change your controller into LinkSwitch-TN2 which is an improved version of LinkSwitch-TN.
For more details, you may refer to this application note on page 20.
AN: https://www.power.com/sites/default/files/documents/an-70_linkswitch-tn2_design_guilde.pdf
I hope this information helps. Kindly let me know if you have further questions and clarifications.
Thank you and have a great day ahead.