USB type-A to USB type-c

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MaXi_1246331
Level 4
Level 4
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I hope to connect the host computer with my PCB board. The?host computer has USB type-A receptacle. The PCB has USB type-C receptacle. I should use a USB type-A to USB type-C cable with plugs on both endpoints.

Because the?USB type-A do not has a CC pin. The DFP computer would not have a pull-up resistor at the CC pin. How to identify the orientation? Does the cable contains a pull-up resistor itself?

How to do with the USB 2.0 D+ and D- pins. Shoud I just directly connect DP1 with DP2 and DN1 with DP2 at the USB type-c receptacle at the PCB?? This style of connection does not need a switch, will it break the rules of signal integrity and results failure??

I use CyUSB3014 in my old design, is it recommended to use a modern device to accomodate the? USB type-C usage?

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JayakrishnaT_76
Moderator
Moderator
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First question asked 1000 replies posted 750 replies posted

Hello,

Please refer to the following KBA to understand how to design FX3/CX3 based type C products.

https://community.cypress.com/t5/Knowledge-Base-Articles/Designing-FX3-CX3-Based-USB-Type-C-Products...

In your case, I find that the PCB will be having a type C receptacle. So, you can refer to the section FX3 Type-C Receptacle Design of the KBA mentioned above.

In addition to the connections shown in the KBA, some MUXs  (Eg: PI5USBxx) have both mux and re-driver inside. Sometimes, external re-drivers are used along with MUX. For mux + re-driver designs, we recommend that the AC caps should be added on both TX and RX lines and on both sides of the mux. That is, AC caps should be present on both TX and RX lines between mux & receptacle and also between mux & FX3 for a mux + re-driver design.
If it is a mux only design, then AC caps are required only on TX lines on both sides of mux. That is AC caps should be placed only on TX lines between mux & receptacle and also between mux & FX3 for a mux only design.

Regarding the USB 2.0 lines on the receptacle side, you can just short them as shown in the KBA. It will not break the rules of signal integrity.

Regarding the following question:

"Because the USB type-A do not has a CC pin. The DFP computer would not have a pull-up resistor at the CC pin. How to identify the orientation? Does the cable contains a pull-up resistor itself?

>>It is handled by the cable itself.

Best Regards,
Jayakrishna

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JayakrishnaT_76
Moderator
Moderator
Moderator
First question asked 1000 replies posted 750 replies posted

Hello,

Please refer to the following KBA to understand how to design FX3/CX3 based type C products.

https://community.cypress.com/t5/Knowledge-Base-Articles/Designing-FX3-CX3-Based-USB-Type-C-Products...

In your case, I find that the PCB will be having a type C receptacle. So, you can refer to the section FX3 Type-C Receptacle Design of the KBA mentioned above.

In addition to the connections shown in the KBA, some MUXs  (Eg: PI5USBxx) have both mux and re-driver inside. Sometimes, external re-drivers are used along with MUX. For mux + re-driver designs, we recommend that the AC caps should be added on both TX and RX lines and on both sides of the mux. That is, AC caps should be present on both TX and RX lines between mux & receptacle and also between mux & FX3 for a mux + re-driver design.
If it is a mux only design, then AC caps are required only on TX lines on both sides of mux. That is AC caps should be placed only on TX lines between mux & receptacle and also between mux & FX3 for a mux only design.

Regarding the USB 2.0 lines on the receptacle side, you can just short them as shown in the KBA. It will not break the rules of signal integrity.

Regarding the following question:

"Because the USB type-A do not has a CC pin. The DFP computer would not have a pull-up resistor at the CC pin. How to identify the orientation? Does the cable contains a pull-up resistor itself?

>>It is handled by the cable itself.

Best Regards,
Jayakrishna
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