Design Low Power Design Isolated 5VDC/1W

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Good Morning all
I am an industrial electronic engineer; I want to develop a low cost and isolated stabilized power source:
-Input AC Voltage Universal (85V-265V)-
-Out CC Voltage 5V DC
-Output Power 1W
-Output current 200mA
I have already used your tools PI expert to design this Feedback Power based of integer circuit LNK623.
I need your recommendations to anticipate risks and optimization if possible?
Is there another equivalent of the transformer PC40EE13-Z?
You can find attached my concept and BOM.
Also, I search to make all components type SMD.
Best Regards

AttachmentSize
BOM Components234.22 KB
schematic of Low Power Source 40.19 KB

Hi Walidayari!

Thank you for contacting us. If you are looking to design a constant voltage converter LNKCV (LNK623) is the perfect chip for you.

Based on the schematic attached,

1. The BP cap should be connected to the bias winding to lessen the no load consumption.

2. You can refer to the application note or design guide for LNKCV Family on the link below

https://ac-dc.power.com/design-support/product-documents/application-notes/an-45-linkswitch-cv-design-guide/

3. And also you can you DER831 as a design example for you.

https://ac-dc.power.com/design-support/reference-designs/design-examples/der-831-25-w-non-isolated-flyback-power-supply-using-linkswitch-cv/

4. You can use a dog bone inductor for the power inductor for cost reduction.

5. As for the transformer material core there are many type of core materials you can use PC45, PC47 depending on the transformer application (temperature, Bmax) You can use the reference below

https://www.ferrite.com.ua/power_cores/images/tdk_pc40_pc47.pdf

If you have further questions, please feel free to ask me again. Thank you.

Best Regards,

PI-Bucky

This is also a good reference for the transformer materials

https://product.tdk.com/info/en/catalog/datasheets/ferrite_mn-zn_material_characteristics_en.pdf

PI-Bucky