TPS25730: TPS25730DREFR

Hi Tirthal,

VIN3V3 is used for IC power when the IC is powered by the system (internal power).

If you only intend on using power from VBUS and VIN_3V3 is unused, please Bypass the pin with the CVIN3V3 capacitance. The pin can be left unused and there should be no impact other than the IC being disabled if a USB-C source is not connected to the port.

Thanks and Regards,

Chris

Hi Tirthal,

We do not recommend using LDO_1V5 for powering any peripherals. The pin exists for adding the capacitance.

For LDO3V3, it is only intended to be used for the GPIO and I2C pullup resistors required by the TPS25730. It can also be used to power a CC-line protection device like the TPD2s300 and TPD4s311A. You should not be powering much else from LDO3V3.

Please see the DS for more information on the GPIOs.

Any output, open-drain GPIOs need a pullup resistor to LDO3V3 when used. They can be floating if unused.

The Fault_In pin should be pulled up to LDO3V3 through a 10k resistor when used or unused to ensure it is pulled high.

Thanks and Regards,

Chris

Hi Tirthal,

1. This is fine
2. This is fine
3. Sink_EN_N is an open drain output. It does not need to be pulled down low. You should leave it pulled up to LDO3V3, not pulled low. This just indicates if the sink path is enabled. It defeats the purpose of the pin to tie it to GND through a resistor.
4. All open drain outputs should either be pulled up to LDO3V3 or left floating. CAP_MIS should not be pulled down. 
   1. 
   2. It indicates if a caps mismatch event has occured. This will occur if the USB-C PD source advertises a max power less than the power required by the minimum voltage and operating current.
5. 
   1. This indicates if the connected device is a Debug accessory.

The CC lines should have 330pF of filtering capacitance on each line.

As mentioned earlier, If the pin is an open drain output, it should either be pulled up to LDO3V3 through a pullup resistor, or left floating if unused. If they are outputs, they do not require any controlling and are intended to indicate connection status.

Thanks and Regards,

Chris

Hi Tirthal,

The TPS25730 does not support VCONN, which is only needed for source applications and data applications. The TPS25730 is meant to be a barrel jack replacement that only support the sink power role.

I primarily reviewed the changes requested in the last thread, everything recommended their looks fixed now.

For pins 26,27, and 36. You can tie these directly to ground, they do not need 10k pulldowns.

The VBUS node (anything connected between the VBUS pin of the type-c connector and the VBUS pins of the TPS25730) should have max 10uF cap. It seems like you have more than 34.7uF between C51, C77, C78, and C56, not including all the other caps you have on the bus. The total cap must be 10uF max which is defined by the USB-C PD spec for sinking ports.

The schematic looks good otherwise.

Thanks and Regards,

Chris

Hi Tirthal,

Just to clarify, the C59,C60,C61,C62, and C54 caps to "place near the pins"  should be placed near the J2 connector VBUS pins. The recommendation is for the connector VBUS pins, not the PD controller PD pins. As long as the 4.7uF is near the TPS25730, it should be fine.

VBUS Cap looks better now, but you still have >10 (14.7uF with C56 and C51). We still recommend it stays under 10uF.

Thanks and Regards,

Chris