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USB EZ-PD™ Type-C Forum Discussions

Swang4004
Level 1
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First question asked Welcome!

I am looking to make use of the CYPD3177 chip and need the specifications relating to the VBUS_FET_EN and SAFE_PWR_EN pins. The datasheet states that I should contact support for details.  I am planning on using around 60w of USB PD power but an exact amount has not yet be determined.

 

Additionally the pin description listing shows a GPIO pin but I see nothing in the datasheet regarding it or the HPI interface pins. Is there a separate document that goes into detail about the capabilities of these pins?

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Abhilash_P
Moderator
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25 likes received 250 replies posted 250 sign-ins

Hi,

 

  VBUS_FET_EN: The VBUS_FET_EN pin is a PFET gate driver that drives to either 0 V or VBUS_IN depending on the state of the Type-C connection. The internal structure of VBUS_FET_EN is just like the VBUS_P_CTRL of CCG3PA. 

The internal MOS has its own Rds(on) which cause the VBUS_FET_EN not exactly 0V or VBUS_IN voltage. And CYPD3177 do not have other pins to display whether a PD contract is established.  If you want customized usage of GPIO, you should switch to CCG3PA instead of BCR since it is a fixed-firmware part.

Abhilash_P_0-1630855890760.png

 

SAFE_PWR_EN: SAFE_PWR_EN is a PFET gate driver that can be used to provide power to the system when an incompatible power adapter is attached to the system. SAFE_PWR_EN is driven to 0V when the Type-C power adapter cannot supply a voltage within VBUS_MIN and VBUS_MAX settings and/or supply a current of at least ISNK_COARSE + ISNK_FINE value. In this case, the EZ-PD BCR device negotiates for a 5V@ ISNK contract with the USB-PD Power Adapter when possible. SAFE_PWR_EN pin is left floating (High-Z) in all other conditions.

DC Specifications:

Abhilash_P_1-1630856127055.png

 

AC Specifications:

Abhilash_P_2-1630856173987.png

 

"Additionally the pin description listing shows a GPIO pin but I see nothing in the datasheet regarding it or the HPI interface pins. Is there a separate document that goes into detail about the capabilities of these pins?"

  Yes, please refer the HPI document that can be found in this link.

Let me know if you require any additional details.

 

Regards,

Abhilash P

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Abhilash_P
Moderator
Moderator
Moderator
25 likes received 250 replies posted 250 sign-ins

Hi,

 

  VBUS_FET_EN: The VBUS_FET_EN pin is a PFET gate driver that drives to either 0 V or VBUS_IN depending on the state of the Type-C connection. The internal structure of VBUS_FET_EN is just like the VBUS_P_CTRL of CCG3PA. 

The internal MOS has its own Rds(on) which cause the VBUS_FET_EN not exactly 0V or VBUS_IN voltage. And CYPD3177 do not have other pins to display whether a PD contract is established.  If you want customized usage of GPIO, you should switch to CCG3PA instead of BCR since it is a fixed-firmware part.

Abhilash_P_0-1630855890760.png

 

SAFE_PWR_EN: SAFE_PWR_EN is a PFET gate driver that can be used to provide power to the system when an incompatible power adapter is attached to the system. SAFE_PWR_EN is driven to 0V when the Type-C power adapter cannot supply a voltage within VBUS_MIN and VBUS_MAX settings and/or supply a current of at least ISNK_COARSE + ISNK_FINE value. In this case, the EZ-PD BCR device negotiates for a 5V@ ISNK contract with the USB-PD Power Adapter when possible. SAFE_PWR_EN pin is left floating (High-Z) in all other conditions.

DC Specifications:

Abhilash_P_1-1630856127055.png

 

AC Specifications:

Abhilash_P_2-1630856173987.png

 

"Additionally the pin description listing shows a GPIO pin but I see nothing in the datasheet regarding it or the HPI interface pins. Is there a separate document that goes into detail about the capabilities of these pins?"

  Yes, please refer the HPI document that can be found in this link.

Let me know if you require any additional details.

 

Regards,

Abhilash P

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