QN908x is not getting recognized as a USB device 1.8V

[kishansa]

Tested this behavior by using the QN908x development board, where configured the QN908x power supply voltage to 1.8V by configuring Jumper JP7.
After this if we connect the QN908x USB port to the PC directly then it gets recognized with out any hick ups.
But when we connect the QN908x USB port output to the USB Hub which was connected to the PC, then QN908x not gets recognized. This setup works fine when we change the QN908x power supply voltage to 3.0V.

Is there any way to make QN908x work at 1.8V (considering user going to use USB Hub with QN908x) because we already designed the system with low power.

[kishans]

Hi Ricardo,

Thank you am doing good. 

I have tried multiple USB HUB and the result are same across. 
I have used CR2032 battery to power up the QN908x module of QN908x Development board. And when I connect this board to any USB hub D5 diode turns ON just like when I insert the dev board directly to the USB slot of the mother board but USB stack is not getting initialized (in usb_device_hid_mouse_freertos example code - when the QN908x gets recognized by the host system ,we can see mouse cursor automatically moving around - this behavior can only be seen when the QN908x modules supply voltage set to 3v. 

[Ricardo_Zamora]

Hi,

Could you try the same scenario but without the coin battery? (Getting the power Supply by the USB interface).

The JP7 Selects the VCC PWR (3.3V or 1.8V), but these two voltages come from a voltage regulation of the USB_VBUS.

The Voltage of the Battery goes "almost directly" to the QN VCC pin. (There are no voltage regulators).

When you use a Battery, you need to let JP16 Open.

You can find more information about the internal connections of our board in the Design files for QN9080-DK (QN9080DK).

Regards,

Ricardo

[kishans]

Hi Ricardo,
I tried with out coin cell and tested this on a three USB hubs and the result is the same as before. Can you share the USB Hub details so that will try to get that here and test it.

Regards,  
  kishan

[Ricardo_Zamora]

Hi kishan,

What is the scenario you tested? With the battery and with JP16 Open?

I have tested with multiple scenarios and everything works fine. (with Battery, JP16 Open/Close, JP7 3/1.8).

I would recommend to test it with other USB Hub from a different manufacturer, and also with another computer.

Regards,

Ricardo

[kishansa]

The above scenario tested using the QN908x SDK Example - usb_device_hid_mouse_freertos. And tested this in MAC OS and Windows OS and the results are the same - ie, its not getting recognized when we use the USB HUB ( which has the option to connect 4 usb device). It looks like when we run QN908x with 1.8V its not able to drive the communication with the host. 

[Ricardo_Zamora]

Hi,

Hope you are doing well. Have you tried another USB Hub? What else are you connecting on the Hub? Have you tried another USB cable?

We have tested it with different computers and Hubs, and it can work on 1.8V. So it seems to be something in your hardware environment, which cannot work with 1.8V, so I would recommend that you try it with another Hub.

Regards,

Ricardo