TUSB2E221: eUSB repeater power consumption in active and idle modes

Hi Jack,

The maximum power consumption in idle, LS/FS, and worst-case is listed in the datasheet.  

The power consumption will vary based on USB bus activity.  The best way to get an estimate on the power is by using an EVM. ~26mW during HS idle as shown in the datasheet, and I have measured 144mW in the lab while actively transferring data to a USB stick.

Regards,

Nicholaus

Hi Nicholaus,

Yes, I checked the datasheet and saw these data.

I am concerned that implementing more eUSB2 repeater ICs in personal systems in the future will cause extra power consumption in both active and idle modes.

For example, if a personal system is designed with 3 USB ports, a camera, a fingerprint scanner, and a card reader, we will need at least 3 dual-port eUSB2 repeater ICs. The idle power consumption will be 78mW (26mW x 3), and the active power consumption will be 432mW (144mW x 3).

If there is anything I misunderstand, please advise or provide your estimation for the above design case.

Thanks.

Jack

Hi Jack,

Yes, you understand correctly.  If you use 3x the devices it will consume 3x the power.

However, if all of those devices you mentioned are USB devices.  Then I would expect you to only use 1 eUSB repeater between the SoC and a USB hub.  The USB hub would create the additional USB ports.  

SoC->eUSB repeater->USB HUB

Regards,

Nicholaus

Hi Nicholaus,

Thank you for the information.

I'd like to confirm with you where the 144mW you mentioned is defined in the datasheet.

26mW is "PHS_IDLE_LP_1", correct?

Jack

Hi Jack,

The 144mW is not in the datasheet.  The power consumption will change based on the USB bus activity, so it is difficult to provide a typical value for TUSB2E221 power consumption.   I measured 144mW in my test setup in the lab with 1 EVM during data transfer, but that value is not representative of all devices across voltage, temperature, and system.  It is meant to be a rough estimate.

Regards,

Nicholaus

Hi Nicholaus,

Thanks for your feedback.

I understand that this is a rough estimation based on EVM measurements.

Is "during data transfer" similar to the condition described below?

Jack

Hi Jack,

Can you tell me the customer and project name?

Thanks,

Nicholaus

Hi Nicholaus,

There is no project name now.

The investigation is for HP products with Intel next generation platforms that supports eUSB2.

Thanks.

Jack