My goal is to create a very low-cost converter that charges a USB Type C device from an existing 20V DC supply. My converter will have 20V input and USB Type C output. The device to be charged will then plug into my converters USB Type C output. I expect the hard part to be the analog power converter, which I can do. So, I am looking for a low-cost controller that will do the negotiating with the device to be charged and send control signals to my power converter circuits. If it matters, the device to be charged is capable of consuming the full 100W. However, I presume there is a trade-off between cost and power output. I should also mention that the device being charged is a laptop or something similarly beefy that expects to be a host normally.
Please direct me to a reference design for how to use a Cypress chip to charge a USB Type-C device from a steady voltage supply. Ideally, easy-to-understand documentation about the cost trade-offs between a 15W "Type-C only" solution vs. a full "Type-C PD" 100W solution would be included.
If a reference design is not possible, I would love a brief introduction as to how to achieve something like this. For example, do I need to create a host down-stream facing port (DFP) or can I get everything I need in a simpler/cheaper EMCA controller? If I create a DFP, then I hope I don't need an EMCA even if I want the full 100W.
