TPS25830A-Q1: Can the output be used to power USB hub IC?

Also, can upstream VBUS be used to power TPS25830A-Q1?

Hi Wei,

Can you please provide a block diagram so I am 100% aligned on the system architecture?

BR,

Seong

Please see attached. It's not complete but shows what we want to do.

Hello Wei Xao,

Table 10-7 in the TPS25830A-Q1 datasheet shows that for the BUCK REGULATOR/VBUS to output 5V, CC1/CC2 must sense Rd and Ra termination resistors.

This means that unless you are using discrete resistors, you will not get output on VBUS unless a type-c Sink device is connected to the type-c port and exposes Rd and Ra resistors.

If I understand the diagram correctly, are you planning to connect the TPS25830A-Q1 VBUS to the USB HUB IC and 4 type-c ports?

BR,

Seong

Yes. If this IC doesn’t work that way, can you please recommend one that would work? Thank you.

Basically, the output can power hub IC and downstream ports, and at least one of the downstream port support battery charging.

Hello Wei,

This means that the HUB IC and the 3 ports will only get VBUS when there is a Sink device connected to the type-c port labeled "USB4". The TPS25830A-Q1's recommended max output current is 3.5A. Is 3.5A enough to distribute to all 4 ports and the HUB IC? 

BR,

Seong

3.5A is adequate. However，we don’t want the VBUS to depend on the CC1, CC2 connection.

Hello Wei,

What do you need to trigger VBUS then?

BR,

Seong

VCC power or VBATT present, which we can use switched power like ACC

Will it cause any problems if the type-C port connects to a device? Can it still support type-C(3A) + CDP? What’s the charging current if a type-C to lightning cable is used to connect, say, an iPhone 13?

Another quick question. The datasheet says 4.5-36V input power supported, but eval board says 6v at least. Will 5v from upstream port work in this case?