BQ27530-G1: Not Responding

Hi Wyatt

I can't probe the pins directly but the input cap on that pin is connected to the battery. This is what SDA and SCL look like when trying to address the chip and there seems to be no acknowledge

Hello Anthony,

The gauge is either not getting power or it is damaged. From your schematic and cannot tell where the other power nodes are connected.

Are you using bqStudio to communicate with the gauge?

Sincerely,

Wyatt Keller

I am not using bqstudio to communicate. We are communicating with the device through a Nordic IC.

Also, I probed the BI/TOUT pin and it was at 2.6V, so I assume that the chip is being powered but I don't know. Does this seem like a normal operational voltage for that pin?

Hello Anthony,

Make sure the gauge is not is ROM mode as well, if you had just programmed it it may still be in ROM mode.

Without the measurements on CE and REGIN it will be hard to know the state of the guage is. I would also try using the EV2400 since it should also detect if it's in ROM it will readout fffff_ffffff as the device version. You will need an EV2400 regardless to program the chem ID.

Sincerely,

Wyatt Keller

What is ROM mode? I did not see that in the datasheet.
"I would also try using the EV2400 since it should also detect if it's in ROM it will readout fffff_ffffff as the device version". We aren't able to get any response from the IC at all. The IC is giving a NACK to the initial address byte of the I2C transmission. 

We tried changing the address to 0x16 but we are still receiving NACK on the address byte. 

Hi Wyatt,

We are able to get the IC to acknowledge i2c messages now, but we are running into other issues. It looks like the IC is performing some sort of clock stretching techniques, but this is confusing the micro. Can you confirm from these screenshots of the sda and scl lines what is happening/is there anyway to suppress clock stretching on the IC? The datasheet makes it sound like clock stretching is a non-configurable characteristic of the device. There will be a screenshot of a full sequence of messages followed by zoomed in screenshots of individual message for visibility. The sequence of messages is an attempt to read the voltage register of the device. Thanks.