EZ-PD BCR - different behaviour Type-C vs. PD

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AlKo_4405501
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Hello,

I'm using the CYPD3177 BCR Kit. I experience different behaviour of the DC_OUT port (controlled by P-MOSFET / VBUS_FET_EN) when I'm either using a PD capable source (PDO 5V 1A) or a 'simple' Type-C source (10k pull-ups on CC lines to 5V -> 5V 3A). I can read the PD_STATUS and the TYPE-C_STATUS registers via I2C. As far as I can tell the port controller detects the type-c source correctly (port is connected, source is attached, Rp of partner device suggests current level 3A, etc.).

With the Type-C source the P-MOSFET is activated rather late. We are talking about approx. 3.5 seconds between making a connection and enabling the output.

With the PD capable source the output is at 5V rather quick (< 1s).

What are the conditions for the CYPD3177 port controller to activate the MOSFET / the power output?

Is there a difference in decision making or with the timings based on the power source?

Best regards
Alexander

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1 Solution
YiZ_31
Moderator
Moderator
Moderator
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Hi Alexander,

For a full-featured Type-C source with PD communication, the PD contract could be estbalished very quickly.

For a dummy Type-C source with cc pulled up, it is not capable of PD communication. Then BCR have to wait for PD message until time out, then it will recognize it as a  dummy source.

Regards,
Eddie

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1 Reply
YiZ_31
Moderator
Moderator
Moderator
1000 replies posted 750 replies posted 500 replies posted

Hi Alexander,

For a full-featured Type-C source with PD communication, the PD contract could be estbalished very quickly.

For a dummy Type-C source with cc pulled up, it is not capable of PD communication. Then BCR have to wait for PD message until time out, then it will recognize it as a  dummy source.

Regards,
Eddie