This device supports four operational modes, to support optimized features and power
dissipation, with the device able to transition between modes either autonomously or
controlled by a host processor.
- NORMAL mode: In this mode, the device performs frequent measurements of system
current, cell voltages, internal and thermistor temperature, and various other
voltages, operates protections as configured, and provides data and status
updates. Battery protections are enabled, and the FET drivers are typically
enabled (in the absence of any protection fault).
- SLEEP mode: In this mode, the device performs
measurements, calculations, and data updates at adjustable time intervals.
Between the measurement intervals, the device is operating in a reduced power
stage to minimize total average current consumption. Battery protections are
still enabled, and the FET drivers are typically enabled (in the absence of any
protection fault).
- DEEPSLEEP mode: In this mode, the FET drivers are
disabled, all battery protections are disabled, and no current or voltage
measurements are taken. The REGOUT LDO can be kept powered, in order to maintain
power to external circuitry, such as a host processor. Communications using
I2C are still active.
- SHUTDOWN mode: The device is
completely disabled (including the internal 1.8 V and REGOUT LDO), the CHG and
DSG FETs are both disabled, all battery protections are disabled, and no
measurements are taken. This is the lowest power state of the device, which may
be used for shipment or long-term storage. All register settings are lost when
in SHUTDOWN mode.
The device also includes a CONFIG_UPDATE mode,
which is used for parameter updates. Transitioning between operational modes is
shown in BQ76907 Operational Power Modes.