USB-PD AC/DC reference design following DER-803

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We are looking into designing a USB-C-PD power supply and want to make use of the INN3379C with GAN FET. I have found the reference design DER803 really useful. If I would use 2x flyback converter would it be enough to use one EMI filter and rectifier bridge like in the DER-803 reference design or two. Basically would like to have 2x USB-C-PD outputs controlled. That means 2x individually 5V/3A 12V/3A 20V/3A controlled via a USB-C-PD controller.
I'm open for any advice for a compact and powerful design.

With Regards,

Hi pittner,

Thank you for considering Power Integrations products.
A power supply with two flyback converters using one input rectifier stage is possible, you may refer to a previous design DER-551.
It is important to properly size the input bulk capacitors such that the rectified DC voltage ripple is acceptable when both converters are at full load, especially at low line input.
To meet EMI, values of the CMCs, x-cap, and y-cap must be evaluated.
Shield winding in the transformer generally helps, and of course proper PCB layout.
You may also want to check our recent, ultra-compact design DER-600 45W USB PD
The total output power for your design would exceed 75W. If power factor correction circuit is required, you may want to consider HiperPFS-4, our PFC controller product family.
A reference design for a 100W USB PD with PFC stage is in the link below.