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USB EZ-PD Type-C

ScottK_91
Employee

Hello,

It is understood that the CYPD-3177 (BCR) does not support legacy or PPS charging profiles. 

If the BCR enabled product is resistor set for 5V@2A and is plugged into various charging options below, what would be present on the BCR output, or at the FAULT pin?

USB Ports on Laptops using Type-A to Type-C cable

    Dell laptop USB A port – 5.08V  0.50A

    ThinkPad USB A port – 5.09V  0.48A

    ThinkPad USB A SS port – 4.85V  1.15A

Adapters with only 5V Output using Type-A to Type-C cable

    Apple 12W USB power adapter – 4.92V  1.61A

    Samsung 5V 2A USB power adapter – 5.33V  1.76A

    Saltillo 15W USB power adapter (no resistors on D+/D-) – 5.11V  0.44A

    Saltillo 15W USB power adapter (75K/25K resistors on D+/D-) – 5.01V  1.62A

Adapters with Adaptive Power

    Samsung 5V 2A, 9V, 1.67A Adaptive USB power adapter – 8.91V  1.60A

    ANKER 30W USB-C PD – 9.0V  1.4A

    KunX PD/QC 30W adapter – 9.0V  1.6A

   

Thanks,

Scott

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1 Solution
YiZ_31
Moderator
Moderator

Hi,

I don't have all these device but they should follow the Spec of Type-C.  Please check USB Type-C Specification 4.5.3.2.2.

In this situation, all the proceduce follows Type-C spec not Power Delivery Spec, so the PDO set by resistor won't work. Fault will not be triggered.

All the power adaper should have at least one vSafe5V PDO. That is the request of PD spec.

BCR has two default PDO:

PDO #1: Fixed Supply, 5V, 900mA, Higher_Capability = Yes if VBUS_MAX > 5V else No

PDO #2: Variable Supply, Minimum Voltage = VBUS_MIN, Maximum_Voltage = VBUS_MAX, Operational Current = ISNK_COARSE + ISNK_FINE

If your power adapter do not have PDO that can support 5V/2A, the fault LED will be on. Based on the maximum power of your adapter, I think they can all supply 5V/2A. So I guess they will not trigger fault LED. If your power adapter can only supply 5V/1.5A, the fault LED will be on.

Regards,
Eddie

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3 Replies
YiZ_31
Moderator
Moderator

Hi,

I don't have all these device but they should follow the Spec of Type-C.  Please check USB Type-C Specification 4.5.3.2.2.

In this situation, all the proceduce follows Type-C spec not Power Delivery Spec, so the PDO set by resistor won't work. Fault will not be triggered.

All the power adaper should have at least one vSafe5V PDO. That is the request of PD spec.

BCR has two default PDO:

PDO #1: Fixed Supply, 5V, 900mA, Higher_Capability = Yes if VBUS_MAX > 5V else No

PDO #2: Variable Supply, Minimum Voltage = VBUS_MIN, Maximum_Voltage = VBUS_MAX, Operational Current = ISNK_COARSE + ISNK_FINE

If your power adapter do not have PDO that can support 5V/2A, the fault LED will be on. Based on the maximum power of your adapter, I think they can all supply 5V/2A. So I guess they will not trigger fault LED. If your power adapter can only supply 5V/1.5A, the fault LED will be on.

Regards,
Eddie

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ScottK_91
Employee

Thanks, Eddie.

It's not clear how the BCR will function when it see voltage/current from legacy chargers using a Type-A to Type-C cable.

Example:  If the BCR output is set at 5V and 1.5A, and it is connected to a legacy charger or laptop that supports 5V at 1A, what is present on the BCR output?

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YiZ_31
Moderator
Moderator

Hi,

Sorry for late reply.

A standard USB port would only have 5V/0.9A 5V/1.5A or 5V/3A.

If connected to a legacy charger, BCR will open VBUS gate due to no PD communication. It's behaviour is based on Type-C mechanism.

Regards,
Eddie

Hi
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