BQ76952: BQ76952 can't communicate with EV2400 module (BQ Studio) using I2C protocol

Hi Subhrajit,

What has changed in your setup from a few weeks ago? Are you using the same EV2400 module. Is the EV2400 module updated to the latest EV2400 firmware? Can you show a picture of your connections between the EV2400 and your board?

Matt

Hello sir,

We connect exactly same setup with the same EV2400 module. We connect SDA, SCL & GND from BQ76952 to EV2400.

Our EV2400 firmware version is 0.32 (Latest one).

This is the screen when we open the BQ Stdio.

We successfully able to the latest version of firmware to EV2400 (Version 0.32) but still it's not work. My hardware (BQ76952) works properly. Our I2C pull-up registers connect with REG1 pin. The REG 1 generate 3.3 volt & the voltage between SRP & SRN pin 1.8 volt. CP1 show (battery voltage + 10v). 

Please help

Can you show a picture of your connections between the EV2400 and your board?

Sir you can see we attach SCL, SDA & GND pin of BQ76952 to the EV2400 module port 2 (12C). 

The same way we connect it with EV2400 before. The SDA & SCL line have 3.3 volt (connected with REG1 through Pull-up registor 1.5k).

Thanks for sharing the picture. The EV2400 also has internal pullup resistors to 3.3V.

Are you able disconnect and reconnect the batter from the PCB to power cycle the BQ76952? 

We  tryed disconnect and reconnect the batter from the PCB but still we are not able to connect sir. 

Do you have anything else connected to the I2C pins (like the microcontroller on your board)?

No sir. Nothing connected with I2C pin except Pull-up.. No microcontroller connected with it.

Can you connect a scope or logic analyzer to the SDA and SCL signals? It would be good to confirm there is activity on these pins when you start BQStudio. Also, you may want to try removing the 1.5k pullups (since the EV2400 has internal 10k pullups to 3.3V).

We connect DSO at I2C pins. No activity ovserve at the time of  connection with EV2400

Okay, so maybe the EV2400 needs to be replaced. Do you have another EV2400 module you can try?

Or if you have a BQ76952 EVM, you can remove the I2C jumpers and connect the signals from the microcontroller from the EVM to your board.

Sir our EV2400 detected by computer at the time of firmware update. We can show recent firmware version of EV2400. All three LEDs are turned ON of the EV2400.
Sir how can we identify that our EV2400 need to replace?

Have you tried removing the 1.5k pullup resistors? There should be activity on the I2C pins, so this is why I suggest trying a different EV2400 module if you do not see activity. Or maybe disconnect the EV2400 from your board and then monitor activity on the EV2400 I2C pins.

Something is definitely wrong especially since you say that this worked previously.

Sure sir. I will remove the pullup and inform you shortly sir. 

I am really thankful for your guidance.

Sir I remove 1.5k pull-up resistor then also it not work. Please help.

I suspect the EV2400 might be the issue if there is not I2C activity. You can also try replacing the BQ76952 IC just in case it is damaged and is holding the I2C signals low.