SLUUCP8 June 2024 BQ41Z50
To minimize power consumption and to avoid draining the battery, the device can be configured to shut down at a programmable stack voltage threshold. This function also works in PERMANENT FAILURE mode. When the device is in PERMANENT FAILURE mode, the parameters PF Shutdown Voltage and PF Shutdown Time configure the shutdown threshold.
Status | Condition | Action |
---|---|---|
Enable | Min cell voltage < Shutdown Voltage | OperationStatus()[SDV] = 1 |
Trip | Min cell voltage < Shutdown Voltage for Shutdown Time | Turn DSG FET off |
Shutdown | Voltage at PACK pin < Charger Present Threshold | Send device into SHUTDOWN mode |
Exit | Voltage at PACK pin > VSTARTUP | OperationStatus()[SDV] = 0 Return to NORMAL mode |
Class | Subclass | Name | Format | Size in Bytes | Min Value | Max Value | Default Value | Unit |
---|---|---|---|---|---|---|---|---|
Power | Shutdown | PF Shutdown Voltage | Int | 2 | 0 | 32767 | 1750 | mV |
Class | Subclass | Name | Format | Size in Bytes | Min Value | Max Value | Default Value | Unit |
---|---|---|---|---|---|---|---|---|
Power | Shutdown | PF Shutdown Time | Unsigned Int | 1 | 0 | 255 | 10 | s |
The BQ41Z50 device goes through a full reset when exiting from SHUTDOWN mode, which means the device will reinitialize. On power up, the gauge will check some special memory locations. If the memory checksum is incorrect, or if the gauge or the AFE watchdog has been triggered, the gauge will do a full reset.
If the memory checksum is good, for example, in a case of a short power glitch, the gauge will do a partial reset. The initialization is faster in a partial reset, and certain memory data will not be reinitialized (for example, all SBS registers, last known FET state, last ADC and CC readings, and so on), and so a partial reset is usually transparent to the host.