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USB EZ-PD Type-C

New Contributor

Hi,

Does setting a requested current mean that only PDO within the requested current range

will be allowed? I want to request a max of 5A but do not mind current all the way down to

1A. The datasheet does not specify what happens in this instance and seems to suggest

that at max it will allow a PDO with a current of 4.1A as a minimum as the fine current

setting can adjust for up to 900mA.

Regards,

Kenny

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Moderator
Moderator

Hi Kenny,

You can check the Capability Mismatch part in PD Spec:

In this case the Sink Shall make a Valid request from the offered capabilities and Shall set the Capability Mismatch bit

What happens next depends on the policy of the power adapter you use.

Regards,
Eddie

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Moderator
Moderator

Hi Kenny,

The minimum current depends on the PDP of power source. Please see Chapter 10 of Power Delivey Spec:

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Regards,
Eddie

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New Contributor

Hi Eddie,

Let me rephrase my question. I am aware of that ultimately the current delivered depends on the PDP

of the power source. I am concerned that if I request 5A and the PDP can only deliver 3A, that no contract

will be negotiated and that the CYPD3177 will default to 5V_SAFE_PWR_EN. Is that the correct behavior?

Regards,

Kenny

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Moderator
Moderator

Hi Kenny,

You can check the Capability Mismatch part in PD Spec:

In this case the Sink Shall make a Valid request from the offered capabilities and Shall set the Capability Mismatch bit

What happens next depends on the policy of the power adapter you use.

Regards,
Eddie

View solution in original post

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