8 Replies Latest reply on Aug 23, 2018 2:04 PM by savic_3623846

    UFP HDMI input PD design over USB type C HDMI Alt mode

      Hi All,

       

      I am designing a HDMI sink device (UFP) over USB type C alt mode. I was reading through CCG3 tech notes and datasheets and I am still confused how I can design the HDMI sink for usb type C using CCG3 type C port controller (if at all we can do that)

       

      I have attached a block diagram of what I think will be the design for UFP HDMI input design over USB type C.

      1. Could you guys let me know if my understanding is correct?

      2. And even in the block diagram (assuming it is correct), I am not sure how the +5V from the HDMI source will be connected to my HDMI chipset. Could you also comment on that?

       

      And on the cable side (from my USB type C receptacle) I saw  a reference design from Cypress using CYPD3120 (link: http://www.cypress.com/documentation/reference-designs/ez-pd-ccg3-based-hdmi-over-type-c-cable-reference-design?source=s… )  - but again this for HDMI output over USB type C.

       

      3. Can this cable be used for HDMI input over USB type C i.e. USB type C on one end which is HDMI input and HDMI connector on other end which is HDMI output?

       

       

      Thank you in advance.

       

      Regards

      SarathUFP HDMI input over USB type C HDMI alt mode.png

        • 1. Re: UFP HDMI input PD design over USB type C HDMI Alt mode
          ShifangZ_26

          Hi Sarath,

           

          1. Could you guys let me know if my understanding is correct?

          >> Your understanding about cable side which a reference design from Cypress using CYPD3120 is incorrect. This is UFP and HDMI sink design. Which is means the HDMI interface will be looking for HDMI monitor.

           

          2. And even in the block diagram (assuming it is correct), I am not sure how the +5V from the HDMI source will be connected to my HDMI chipset. Could you also comment on that?

          >> You are correct that the +5V will be connect to your HDMI chip-set. But the +5V will be comes from VBUS. You can refer to the reference design you have been shared the link.

           

          3. Can this cable be used for HDMI input over USB type C i.e. USB type C on one end which is HDMI input and HDMI connector on other end which is HDMI output?

          >> Refer to #1.

           

          Best Regards,

          Lisa

          • 2. Re: UFP HDMI input PD design over USB type C HDMI Alt mode

            Hi Lisz,

             

            Thank you for your reply. I understand that the reference cable design shown in the link I shared is from USB type C display source to HDMI display sink.

             

            What I wanted to confirm is that the if the UFP design that I showed using CYPD3122 is correct?

            My device is a display sink (like monitor) that has USB type C receptacle connector and wanted use HDMI over alt mode protocol.

             

            1. I have attached the updated block diagram to reflect the +5V from HDMI source connection.  Please have a look and confirm if this block diagram can be used for display sink design of USB type C over HDMI alt mode. As per my block diagram, CC1 and VCONN from USB type C connector will be connected to the CYPD3122. CYPD3122 then provides SCL and SDA lines for communication to HDMI input chipset. Also it provides GPIO lines to switch the data mux. 

             

            2. If there is any changes in terms of connections/pin outs, etc, is needed please let me know.

             

            3. Do you have any reference cable design for the USB type C to HDMI connector where USB type C is connected to a UFP device (display sink) and HDMI is connected to a Display source? I assume the cable reference design link that I had, can not be used in this scenario. 

             

             

            Thank you

            Sarath

             

             

            UFP HDMI input over USB type C HDMI alt mode.png

            • 3. Re: UFP HDMI input PD design over USB type C HDMI Alt mode

              Hi All,

               

              Could any of you help me to confirm if my design is correct?

              It would be great if some one can reply to my questions above.

               

              Thank you very much in advance.

               

              Regards

              Sarath

              • 4. Re: UFP HDMI input PD design over USB type C HDMI Alt mode

                Hi All,

                 

                I hope there will be some reply for my query.  If you need time, please do let me know. I even called your technical support number, but to know that the USB type C support team is in India and can not be emailed or called.

                 

                 

                Its been almost 10 days since I posted my queries and I am stuck now to find a solution. If anyone can suggest an alternate method to contact (Email, call, support ticket) that will be greatly appreciated.

                 

                Hope to get at least an acknowledgment or a response!

                 

                Regards

                Sarath

                • 5. Re: UFP HDMI input PD design over USB type C HDMI Alt mode
                  ShifangZ_26

                  Hi Sarath,

                   

                  1. The reference design (link: http://www.cypress.com/documentation/reference-designs/ez-pd-ccg3-based-hdmi-over-type-c-cable-reference-design?source=s… ) we have been discussed is UFP design but Type-C plug. The difference with your requirements is Type-C interface, the others are the one you are looking for.

                  2. You are designing a UFP design with Type-C receptacle. I do not recommend you design such design, since the Type-C receptacle is much complex than Type-C plug. The limitation is not on CCG3 end from Cypress. It is because the Type-C receptacle have to responsible for Type-C orientation detection, which is means the Data MUX need to support flip-flop the data signals.

                  3. Based on #2, the CCG3's firmware have to customize it as per the hardware design. But the firmware of those type design is not ready, the HEX on the link above (in #1) is only for Type-C plug to HDMI with fixed pin assignments. And SDK of CCG3 is not support HDMI Alt Mode so far, you have to develop the firmware from zero.

                  4. If you could like to design a Type-C receptacle to HDMI dongle, recommend you adapt DisplayPort Alt Mode over Type-C, and then you can refer PS8742B as data MUX.

                   

                  Best Regards,

                  Lisa

                  • 6. Re: UFP HDMI input PD design over USB type C HDMI Alt mode

                    Hi Lisa,

                     

                    Thank you very much for  your reply. I have a few more questions and I am so sorry to bother you.

                     

                    1. So If I understand correctly, if I were to use the block diagram I had shown earlier for HDMI input over USB type C alt mode, we will need to create our own firmware from scratch and there wont be any support from Cypress. Am I correct here?

                     

                    2. If #1 is true, we can go ahead with display port alt mode. Please see the block diagram with display port input over USB type C alt mode i.e. my monitor (with USB type C receptacle) will get the display port data over USB type C and will use cypress CYPD3125 for USB PD control. Please let me know if the block diagram is correct and I can use Cypress CYPD3125 to start my design  

                     

                    3. How will be the hot plug detect out (since our's is the display sink, we will be providing HDP out 5V) be connected for this application? Does it connects to CYPD3125? If yes, then how does the display source get this signal?

                     

                    4. Is there any more signal connections to the CYPD3125?

                     

                    Thank you in advance and I hope to get a reply soon.

                     

                    UFP display port input over USB type C alt mode.png

                    Regards

                    Sarath

                    • 7. Re: UFP HDMI input PD design over USB type C HDMI Alt mode
                      ShifangZ_26

                      Hi Sarath,

                       

                      If you are monitor design, recommend you refer the reference design as below:

                      1. Based on CCG3,

                      a. If you are UFP and Power sink role, You can select CYPD3120 and refer the schematic: http://www.cypress.com/documentation/reference-designs/ez-pd-ccg3-usb-type-c-hdmi-adapter-solution , based on the reference design, we just need add PS8742 into your design. And firmware use CYPD3120-40LQXI_dp_dongle example project.

                      b. If you are UFP and power source role, you can select CYPD3123 for your project. CYPD3125 can support your project, but it is I2C bootloader and billboard is not enabled in notebook reference design. For your design, you need USB bootloadering and Enable Billboard internal. So that, you can use CYPD3123 and customize the code based on CCG3 CTD SDK firmware. The HPD signal shall be pin#35 for CCG3.

                      2. Based on your requirements, you also can refer Cypress reference design: http://www.cypress.com/documentation/reference-designs/ez-pd-ccg4-usb-type-c-monitordock-solution , If so, you can just need to cut cut and cut from the reference design.

                       

                      3. Your block diagram looks fine from my end.

                       

                      Best Regards,

                      Lisa