TUSB8041: Power consumption clarification

Hi Pratham:

   It seems pretty high, what current for 1.1v supply?

Best

Brian

Hi Brian Zhou ,

The current we measured at 1.1V suppply is around 0.220 A (220mA), and at 3.3V supply its 0.075 A (75mA). Looks quite high without any device connected to the port. Can you tell what could be consuming this much?

Best Regards,

Pratham

Is SMBUS pin low?

Best

Brian

Hi Brian Zhou ,

Here's the snap from our schematic design,

We are not using any i2c or smbus to program the hub. Also the FULLPWRMGMT,PWRCTLx, and OVERCURx gpio all are low. We are not configuring any of those.

What voltage on USB_VBus, it should be around 500mv.

Best

brian

Hi Brian Zhou 
On USB_Vbus we are getting 1.1V. 
 
Also can you please suggest how we can power down the ports when no device is connected? Also the port should be powered up after the device detection is that possible? 

Best Regards,

Pratham

Hi Pratham:

  USB_VBUS should be around 500mV.

 If  FULLPWRMGMT is low, power switching is supported and OVERCURR signal should be high. If OVERCURR is low , means overcurrent happened.

   Did you see any USB detection issue? something is wrong for the system.

Best

Brian

Hi Brian Zhou ,

We have tried setting the 500mV on USB_VBUS and no difference was seen in the power consumption.

I believe the hub is not going to suspend mode. Also when we tried toggling the reset gpio  the current consumption reduces only by ~40mA when gpio is low.

Is there any method using which we can put all the ports to suspend mode using linux?

Let me check on TI EVM and see what happens.

Best

brian

I only saw  33ma on 1.1v and  2 ma on 3.3v supply when there is no USB device attached. 

Do you have a good soldering on thermal pad?

Regards

Brian