BQ27505-J4 Datasheet, PDF (13/38 Pages) Texas Instruments – System-Side Impedance Track™ Fuel Gauge

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bq27505-J4
SLVSA40 – DECEMBER 2009
4.1.1.1.19 SEALED: 0x0020
Instructs the fuel gauge to transition from the UNSEALED state to the SEALED state. The fuel gauge must
always be set to the SEALED state for use in end equipment.
4.1.1.1.20 IT_ENABLE: 0x0021
This command forces the fuel gauge to begin the Impedance Track™ algorithm, sets the active
UpdateStatus n location to 0x01 and causes the [VOK] and [QEN] flags to be set in the
CONTROL_STATUS register. [VOK] is cleared if the voltages are not suitable for a Qmax update. Once
set, [QEN] cannot be cleared. This command is only available when the fuel gauge is UNSEALED.
4.1.1.1.21 CAL_MODE: 0X0040
This command instructs the fuel gauge to enter calibration mode. This command is only available when
the fuel gauge is UNSEALED.
4.1.1.1.22 RESET: 0x0041
This command instructs the fuel gauge to perform a full reset. This command is only available when the
fuel gauge is UNSEALED.
4.1.1.2 AtRate( ): 0x02/0x03
The AtRate( ) read-/write-word function is the first half of a two-function command set used to set the
AtRate value used in calculations made by the AtRateTimeToEmpty( ) function. The AtRate( ) units are in
mA.
The AtRate( ) value is a signed integer, with negative values interpreted as a discharge current value. The
AtRateTimeToEmpty( ) function returns the predicted operating time at the AtRate value of discharge. The
default value for AtRate( ) is zero and forces AtRateTimeToEmpty( ) to return 65,535. Both the AtRate( )
and AtRateTimeToEmpty( ) commands must only be used in NORMAL mode.
4.1.1.3 AtRateTimeToEmpty( ): 0x04/0x05
This read-word function returns an unsigned integer value of the predicted remaining operating time if the
battery is discharged at the AtRate( ) value in minutes with a range of 0 to 65,534. A value of 65,535
indicates AtRate( ) = 0. The fuel gauge updates AtRateTimeToEmpty( ) within 1s after the system sets the
AtRate( ) value. The fuel gauge automatically updates AtRateTimeToEmpty( ) based on the AtRate( )
value every 1s. Both the AtRate( ) and AtRateTimeToEmpty( ) commands must only be used in NORMAL
mode.
4.1.1.4 Temperature( ): 0x06/0x07
This read-only function returns an unsigned integer value of the temperature in units of 0.1K measured by
the fuel gauge.
4.1.1.5 Voltage( ): 0x08/0x09
This read-word function returns an unsigned integer value of the measured cell-pack voltage in mV with a
range of 0 to 6000 mV.
Copyright © 2009, Texas Instruments Incorporated
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GENERAL DESCRIPTION
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