BQ78350-R1: BQ78350R1 and BQ76940

Hi March Jasper,

If you do now want to detect the inrush current that you have in your lifetime, there are a few settings that you can configure:

Overcurrent in charge (In the BQ78350-R1 TRM Rev. C Section 3.4):
There is a current limit.
You will see there is also a OCC Delay setting that can configured.

By default, the delay is set to 6s but can modified up to a maximum 255s. If the duration of your inrush charge current is longer than this, then I don't think I would consider that an inrush current but more of a normal operating condition.
In the flash of BQ78350-R1, the OCC delay setting is located at address 0x44D8 (found Table 19-1. Data Flash Summary Table in the TRM)

You have two options in terms of BQ78350:
Increase your time to detection: You will have to determine whether in all other circumstances (when not charging the first time), the longer delay is acceptable.
Increase the current limit: Since the inrush current is just above the 11A limit, increasing to say 11.5A should not be a major issue.

Regards,
Michel

Hi March Jasper,
As Michel indicates, you can change the OCC Threshold and Delay in the configuration, see section 3.4 of the bq78350-R1 TRM.
a) Lifetime current is the maximum of the "Current", which as shown in 17.12 is the average of 4 CC values. The CC values are available every 250ms. So if the inrush results in a CC value of 10000 on one sample and the others are 0, this should give a Current of 2500 for one value before returning to 0 and the LT Max Charge Current should be updated to 2500 mA. The OCC Threshold and delay should be able to be set to avoid trigger, default would not trigger. If you do want to detect the inrush with OCC, the success will depend on your system behavior. You can set the threshold low and delay to minimum, but eventually this may interfere with normal current.
The lifetime max charge current will update to the peak value, it does not have a filter to disqualify inrush peaks.

b). Detection of the charge surge would need to be done by the OCC in the bq78350. The bq76940 does not have a hardware detection for OCC.

In the discharge direction the current measurement and lifetime work similarly. The bq78350 OCD settings will also work similarly. The bq76940 does have hardware OCD and SCD settings configured in the bq78350-R1 as AOLD and ASCD some of which can respond faster than the CC, but those don't show up in lifetimes, it is the CC values filtered into Current which are recorded as lifetime maximums.