3 Replies Latest reply on Dec 13, 2018 1:33 AM by SananyaM_56

    Powering tablet with 5V - 3A supply....



      I am working on a hardware (which acts as host) where it has USB 2.0 ports and connects to tablet over USB 2.0 (tablet acts as device).


      I am able to communicate with tablet (using RNDIS) and need to supply the power it as well. Need of the power supply is 3A at 5V which I would not be able to do from my hardware.


      I have a separate power source which can give me 5V - 3A and wnated to know if there is any way I can combine with USB (as there is only USB micro getting connected to tablet) using some thing like Y connector. Or do you have any suggestion using any hub (like cypress HX3 or similar) which can do this?


      With best regards,


        • 1. Re: Powering tablet with 5V - 3A supply....



          If you use HX3 with your 2.0 host, you could configure the downstream port as a CDP or DCP and connect to your host but it can support upto 1.5A as per BCv1.2. Please use a higher current adapter for HX3 to satisfy the higher charging current of your downstream port.

          Please refer to the KBA for more details on the charging implementations for HX3.


          Best Regards,


          • 2. Re: Powering tablet with 5V - 3A supply....

            Hi Sananya,


            Thanks for your reply!!! I downloaded the link (

            http://www.cypress.com/file/134011/download) you sent and seems it suits my



            Couple of questions

            1. By default this would be supporting the CDP right? I mean I do not need

            any I2C flash or so to configure HX3? Any way table 3 says, by default it

            is CDP mode.

            2. Table 6 says (for CY4609) downstream maximum charging current is 4.8A

            for all downstream ports (also note 3 says, it should not exceed 3A). So is

            it ok, if I use only one DS (downstream port) in CDP mode and if I can use

            this to charge my tablet (which will take at max 3A)?

            3. Is this HX3 DVK for CY4609 is available in India? If yes, how much time

            it will take to ship it to Bangalore?


            With best regards,


            • 3. Re: Powering tablet with 5V - 3A supply....

              Hi P.,


              1. Yes by default it is set as CDP but for 3A requirement it is recommended to set it as a DCP. However, the exact current drawn will depend on your device.

              2. According to the note, the current should not exceed 3A in each downstream port so it is alright if you use the 5V-4A adapter that comes with the kit for charging only your tablet. Please ensure that the power switch in DVK is set to the appropriate current limit with variable resistor.

              3. You can only order the DVK from the Cypress website and since it is shipped from outside India, it may take around a week to be delivered.


              Best Regards,