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In the DataSheet for the CCG3 it shows a 10 μF capacitor on the VBUS line for DRP and DFP designs. It is 1 μF for UFP. I'm designing a DRP device and I find that when I'm sinking power, this 10 μF capacitance causes a 5 second delay if the power source is turned off and turned back on. Can I reduce the size of this capacitor?
The VBUS_DISCHARGE pin doesn't seem to be able to discharge the capacitor below 1.8 V. The two power sources I've tested won't provide 5V until the line drops to 0.8 V.
My last resort is to use a 10 kΩ resistor in parallel to the capacitor, but I would rather use a smaller capacitor.
Solved! Go to Solution.
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The USB-PD specification says "Source Bulk Capacitance" must be added to the VBUS.
And the capacitance value is specified as follows.
So, 10uF is required for DFP or power source.
I am referring "USB Power Delivery Specification Revision 2.0, Version 1.1"
Regards,
Noriaki
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The USB-PD specification says "Source Bulk Capacitance" must be added to the VBUS.
And the capacitance value is specified as follows.
So, 10uF is required for DFP or power source.
I am referring "USB Power Delivery Specification Revision 2.0, Version 1.1"
Regards,
Noriaki
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Hi,
Kindly refer below explain as per PD3.0 SPEC:
1. 10 μF capacitor on the VBUS line for DRP and DFP designs, USB Power Delivery Specification Revision 3.0, Version 1.2
2. The two power sources I've tested won't provide 5V until the line drops to 0.8 V.
Best Regards,
Lisa
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I've decided leave the 10 μF in place and add a 33 kΩ resistor. This is the largest resistance that can discharge the capacitor from 5 V to 0.8 V in tSafe0V (650 ms).