VBUS supply timing in HX3

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
TeMa_2997106
Level 6
Level 6
Distributor - TED (Japan)
10 likes received 10 solutions authored 250 replies posted

Is there a Power-up sequence for VBUS_DS and VBUS_US in HX3?

Can it supply 5V regardless of the rise of 1.2V or 3.3V?

Thanks,
Tetsuo

0 Likes
1 Solution

Hi Tetsuo-san,

There is no Power sequencing requirement for VBUS_US.

After Power-up, HX3 will provide the termination resistor(on the data lines) for enumeration only when VBUS_US is high.

Thanks,
Ajeeth

View solution in original post

0 Likes
4 Replies
Ajeethkumar_P
Moderator
Moderator
Moderator
50 likes received 500 replies posted 100 solutions authored

Hi Tetsuo-san,

Thanks for posting in the Infineon Developer community.

VBUS_US and VBUS_DS are the PWR pins.

VBUS_US pin is used for detecting VBUS from the US port and when VBUS Detection is not needed(For Ex. Embedded Hub), this pin should be tied to VCC_5V with 10K Resistor divider.

VBUS_DS pin is used to power the Apple-charging circuit in HX3. 

For more details, please refer to the HX3 datasheet.

Thanks,
Ajeeth

0 Likes
TeMa_2997106
Level 6
Level 6
Distributor - TED (Japan)
10 likes received 10 solutions authored 250 replies posted

Ajeeth-san,

If it connects VBUS_US to a local 5V, is there a power-up sequence?

Thanks,
Tetsuo

0 Likes

Hi Tetsuo-san,

There is no Power sequencing requirement for VBUS_US.

After Power-up, HX3 will provide the termination resistor(on the data lines) for enumeration only when VBUS_US is high.

Thanks,
Ajeeth

0 Likes
TeMa_2997106
Level 6
Level 6
Distributor - TED (Japan)
10 likes received 10 solutions authored 250 replies posted

Ajeeth-san,

Thank you for your support.
I could understand.

Thanks,
Tetsuo

0 Likes