TUSB2046B: not working

Hi Shinu:

  Here are issues I found form schemaiic:

1:  pin 26 EXTMEM should be directly pulllup to 3.3v.

2:  there are two 1.5k pullup to 3.3v on DP0, only one is needed.

3: No 1.5k pullup needed on DP1.

4: There is no 5v for downstream port 4.

5:  what status on pin6 GANG mode?

Regarsd

Brian

Hi Brian,

Thanks for the inputs. Customer done the correction and below are the feedback. 

1. Pin26  EXTEMEM pin I pulled up through 4.7K ohm, I already made R368 #4.7K DNP.
2. Additional 1.5K on DP0 removed
3. DP1 pullup 1.5K removed
4. Pin 6# ganged pin is grounded, I’ve made R366 # 33 ohm DNP.
5. There is no 5v for downstream port 4. ? 

What does it exactly? Is it HUB port4 or TPS2044 pin 10? As I’m using only 3 down stream port for USB device and one port is for FT230 IC which is running on board 3.3V supply. 

I implemented but result is same. Now whenever I removed keyboard  port 2 device, COM port is also get disconnected

(I don’t see any com port on device manager, once I connect keyboard back to port 2 then again COM port gets detected) 

What could be other issue?

Regards, Shinu. 

Maybe that keyboard has issue, did you try other keyboards on port 2 ?  or try that special keyboard on port 3?

Do you have USB analyer to take the USB trace?

Regards

Brian

Thanks Brian,

I will check with customer.

Thanks.