SLUUCA6 October 2021 BQ27Z746
In SHIP mode, the device measures voltage and temperature very infrequently and at shorter ADC conversion times, and current is not measured or coulomb counted. Current is assumed to be and reported as 0 mA. Therefore, the device tracks the battery's state-of-charge from OCVs. The measurements performed at each interval are:
Firmware processing is minimized by reducing the number of calculations. Some calculations are performed less frequently: only after voltage and temperature are measured. These less frequent calculations include updating firmware-based protections, lifetime data, and the voltage and temperature range of the advanced charge algorithm. Other calculations, such as updating RemainingCapacity() and FullChargeCapacity, are not performed at all with the assumption the system is off and will not communicate with the gauge.
SHIP mode is entered based on voltage through SLEEP or by command through NORMAL or SLEEP. Exit from this mode is through a current level or command.
Status | Condition | Action |
---|---|---|
Activate | (OperationStatusA()[SLEEP] =
1 AND Voltage() < Shipmode Voltage Threshold for Shipmode Voltage Delay) OR (OperationStatusB()[SHIPM] = 1 for Shipmode Command Delay AND |Current()| ≤ Sleep Current) |
OperationStatusA()[SHIP] =
1 The device enters RELAX mode. Current() = 0 mA, AverageCurrent() = 0 mA The device wakes up every Shipmode Measure Time to measure voltage and temperature.(1) The device does NOT coulomb count or measure current. |
Exit | (Hardware-based IWAKE threshold
surpassed AND DA Configuration[IWAKE_EXIT] = 1) OR (Voltage() ≥ Shipmode Voltage Threshold AND OperationStatusB()[SHIPM] = 0) OR (OperationStatusB()[SHIPM] = 1 AND MAC ShipmodeDisable() received) |
OperationStatusA()[SHIP] =
0 OperationStatusB()[SHIPM] = 0 Return to NORMAL mode |
If the gauge is UNSEALED and the MAC ShipmodeEnable() command is sent twice in a row, the gauge enters SHIP mode immediately and skips the normal delay sequence.
The configuration options for SHIP are in the following data flash.
Class | Subclass | Name | Type | Min | Max | Default | Unit | Description |
---|---|---|---|---|---|---|---|---|
Power | Shipmode | Shipmode Voltage Threshold | I2 | 0 | 32767 | 2300 | mV | Cell based SHIP voltage trip threshold |
Power | Shipmode | Shipmode Voltage Delay | U2 | 0 | 255 | 10 | s | Cell based SHIP voltage trip delay |
Power | Shipmode | Shipmode Measure Time | U1 | 1 | 30 | 30 | s | Determines the wake interval to measure voltage and temperature in SHIP mode |
Power | Shipmode | Shipmode Command Delay | U1 | 0 | 255 | 0 | s | Delay time to enter SHIP mode after MAC ShipmodeEnable() is received. The device takes an additional 1-2 seconds to enter SHIP mode for command processing |