TUSB4020BI: Two Port USB HUB Not detected

THANGA PRABU

Part Number: TUSB4020BI
Other Parts Discussed in Thread: TUSB8020B

Hi,

We are using TUSB4020BIPHPQ1 part as Two port USB HUB. The USB HUB IC (TUSB4020BIPHPQ1) takes the current of 300mA at 3.26V while we are applying the Input Voltage of 3.3V even no device or component is connected in downstream side. And also the USB HUB IC is not detected in device manager. we verified that crystal is operating at frequency of 24MHz. Could you please resolve this problem?

over 5 years ago

0 Malik Barton57 over 5 years ago

TI__Guru 64326 points

Hi,

Please make sure that TUSB4020BI is configured in I2C mode and remove any blank EEPROM that may be attached. This will prevent TUSB42020BI from entering different programming modes.

0 THANGA PRABU over 5 years ago in reply to Malik Barton57

Prodigy 120 points

Hi Malik,

In Our Board, We don,t use EEPROM IC But we are operating at SMBUSz Mode instead of I2C mode. Whether this is reason for Overcurrent consumption in USB HUB IC and also not detected in device manager?

0 Malik Barton57 over 5 years ago in reply to THANGA PRABU

TI__Guru 64326 points

Hi,

Power consumption and behavior is expected when using SMBUS mode. Please refer note form datasheet below. If you do not want to write over SMBUS use I2C mode and keep in mind that programming of TUSB4020BI is not required for default operation in I2C mode.

0 THANGA PRABU over 5 years ago in reply to Malik Barton57

Prodigy 120 points

Hi Malik,

Ok, Thank you for your quick support. I will change to I2C Mode and I will update you.

Thanks,

Thanga Prabu S

0 THANGA PRABU over 5 years ago in reply to THANGA PRABU

Prodigy 120 points

Hi Malik,

Thank you for your support. I changed to I2C mode and also USB Current Consumption is reduced to 40mA at 3.3V as you said. In our design, 2 port the downstream side is connected to two USB to UART IC.

From the Device manager, It shows one Com Port for one USB to UART IC(mcp2221A), one USB HUB and one USB Composite Device. Could you please help on One non detected com port for USB to UART IC in device manager.

For your reference With USB HUB, Device manager looks below

With out USB Hub, Device manger looks below

Thanks,

Thanga prabu s.

0 Malik Barton57 over 5 years ago in reply to THANGA PRABU

TI__Guru 64326 points

Hi Prabu,

It does not seem like your images uploaded correctly, could you repost? If TUSB4020BI enumerated correctly and you are able to see in the device manager then this may be a issue with the downstream device. I recommend using a program like USBView to understand how your devices are enumerating specifically.