Hello,
I've got another issue concerning the BQ78350-R1 shutdown mode.
On its technical reference manual I read the condition for entering into the Voltage Based Shutdown:
Min(Cell Voltage in Voltages()) continuous < Shutdown Voltage for Shutdown Time
I've noted on some samples that if the red current value is not closed to 0mA the BQ78350 doesn't enter in shutdown. It happes also by sendind the MAC Shutdown on SMBus.
To be more precise, after sending the MAC command or reaching the low voltage condition (i.e. voltage less than Shutdown Voltage value) on a cell, the following sequence of action normally happen:
- the SDM or SDV flags (Operation Status register) switch to high
- after a few seconds both CHG and DSG FETs are switched off (and CHG and DSG flags switch to low)
- after a few second the system enters in shutdown mode
For some samples it happens that the red current sudenly increase to 10-20mA after switching FETs off (of course, such a current should be zero!). We can also suppose it is not a real current, but the problem is that because of such a value, the system does not complet the shutdown sequence and doesnt enters in shutdown mode: it remains in the state at the second step of the above reported sequence.
If I force a CC Offset calibration in such a state, the red current properly drops to zero and immidiately the system complete the shutdowm operation with the real shutdown.
So my questio is: is there any constraint also about the red current for entering in shutdown mode?
Thank you
Matteo
