BQ79731Q1EVM-060: GUI Connection Problem

Hi Viktor,

I tried but doesn't work. I send wake signal but it doesn't work. Do you have any other suggestions? Thanks.

Best Regard,

KT

Hi Korcan,

When you power up the EVM, do you see the AVDD_LED turned on?

Regards,

Viktor

Hi Viktor,

Yes, I can see. Can I send wake up signal with usb2any? I don't have other EVM(bq79718 or bq79600). EVM is shutdown mode until come to wake up signal. Wake up signal is only send with COMH and COML, isn't it? Thanks for support. 

BR,

KT

Hi KT,

Yes, you can wake the device with USB2ANY. The wake up signal is also at the RX pin as well. This is described in the BQ79731 Datasheet.

Can you please do an oscilloscope measurement on the RX pin in order to see if you are receiving this signal?

You can do this at J2 of the evaluation board.

Regards,

Viktor.

Hi Viktor,

When I can check the J2(RX pin) with oscilloscope measurement, I'm showing 5V signal and there is no chance during sending signal. Why can I sent wake up signal with usb2any? Can you have any suggestion about that? Thanks for support.

Regards,

KT

Hi KT,

You should see the 5v - 0v - 5V transition in order for the BQ79731 to wake up. If you don't that means that there is either something wrong with the USB2ANY or the ISO7xxx chip on board U3.

You can measure the same RX signal on the USB2ANY side of the isolation by probing pin 3 of U3. It should be the same signal with 3.3V logic level.

Again, is your jumper J15 removed? This is usually the problem in most cases.

Regards,

Viktor.

Hi Viktor,

Pin 3 of U3 is 0V logic level. There is something wrong with usb2any. J15 jumper is removed. usb2any is connected successfully in the picture below. 

Can you have any suggestion about that? Thanks for support.

Regards,

KT

Hi KT,

It is ok for Pin3 of U3 to be 0V this is just the clock for the SPI interface, but I see from the jumpers configuration that you are using the EVM in UART mode.

Can you tell me what logic level are pins 7 and 10 of the U3?

Also pins 4 and 13 should be High, where pin 4 is 3.3V while pin 13 is 5V.

You can also check the VIO test point, which is pin 16 on U3, this one should also be 5V.

Regards,

Viktor.

Hi Viktor,

 Pin16 is 0V.  Pin 13 is 4.8V and other results are shown below. Yes, you are right. I'm using Uart configuration. What can you suggest ?

pin7 of U3

pin10 of U3

pin4 of U3

Hi KT,

All results here seem normal, I am not sure why can't you wake up the EVM.

Can you order another EVM and try again.

Hi Viktor,

Pin 16,13 and 10 of U3 is low. VIO is low. How can I fix that? 

Thanks for support.

Hi KT,

VIO is supplied from AVDD in the default EVM configuration. You mentioned the AVDD LED is on so this means AVDD and VIO should be high.

Please check the following again.

- Is AVDD = 5V ?

- Is VIO = 5V ?

If AVDD is 5V but VIO is not 5V then check resistor R7 - It needs to be 0 Ohms (short).

Pins 16, 10 and 13 of U3 should all be high when the USB2ANY is connected and the GUI is running.

Without the USB2ANY connected at least pins 16 and 10 should be high (5V).

Regards,

Viktor.