SLUUAQ3A April 2016 – October 2022 BQ4050
The device provides an option for removable packs (that is, DA Config[NR] = 0) to enter SLEEP mode in-system. When the DA Config[IN_SYSTEM_SLEEP] = 1, the device will enter SLEEP mode even if the OperationStatus()[PRES] = 1. This option ignores the PRES pin status only. All the other sleep conditions must be met for the device to enter SLEEP mode.
In the IN SYSTEM SLEEP mode, it is possible to read the [SLPAC] and [SLPCC] flags if [IN_SYSTEM_SLEEP] = 1 and Bus Timeout = 0. This setting allows the gauge to enter SLEEP mode with active communication in progress.
Setting the Bus Timeout = 0 with [IN_SYTEM_SLEEP] can be used for testing purposes, but it is not recommended to set the Bus Timeout = 0 in the field. If Bus Timeout = 0, the device's sleep and wake conditions are strictly controlled by current detection. If the host system performs a low load operation periodically (for example, wireless detection in a tablet application), this small load current may be missed, introducing an error into remaining capacity tracking. Having a non-zero Bus Timeout setting enables the gauge to wake up by a communication and capture the current measurement.