BQ76940: BQ76940: How to activate to 1 DEVICE_XREADY (Bit 5): Internal chip fault indicator.

Valerio Sell

Part Number: BQ76940

Dear TI,

i'm Valerio.I have application with BQ76940,BMS maangement in litium cell.

I try to simulate internal chip fault indicator in demo board with short across to C2 or C3 cap.

i have to simulate internal fault in i2c receive flags :

DEVICE_XREADY (Bit 5): Internal chip fault indicator. When this bit is set to 1, it should be cleared by
the host. May be set due to excessive system transients. This bit may only be cleared (and not set) by
the host.
0 = Device is OK.
1 = Internal chip fault detected, recommend that host microcontroller clear this bit after waiting a
few seconds. Remains latched high until cleared by the host.

I don't view in comunication I2C this bit don't go to 1,how to in demoboard for set to 1 this bit flga?

Thanks

Best Regards

Vale

over 5 years ago

0 WM5295 over 5 years ago

TI__Guru 54715 points

Hi Vale,
See the suggestions in your other post e2e.ti.com/.../2568725
Shorting CAP2 or CAP3 for 1 to 2 seconds should produce XREADY. On the demo board this is easy to do with the test points on the right side. For example connect CAP3 to VC10X. Once XREADY has appeared, remove the short.
When using a power supply with the demo board you could set your supply to a reduced voltage such as 35V (if you are using a bq76940 with 15 cells), then short the cell 10 input to the cell 15 input at the terminal blocks. This will remove voltage from the top cell group and it should have a permanent XREADY until the short is removed.

0 Valerio Sell over 5 years ago in reply to WM5295

Intellectual 310 points

Dear TI,thanks for help me.I try to simulate this bit indicator in demo board.Please select this post as resolved.Thanks.Best regards Vale

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BQ76940: BQ76940: How to activate to 1 DEVICE_XREADY (Bit 5): Internal chip fault indicator.