BQ2083-V1P3 Datasheet, PDF (26/56 Pages) Texas Instruments – SBS-COMPLIANT GAS GAUGE IC FOR USE WITH THE bq29311

bq2083-V1P3
SLVS508 − OCTOBER 2003
www.ti.com
The following functions are calculated on the basis of capacity and may be calculated differently depending on
the CAPACITY_MODE bit:
D AtRateOK( )
D AtRateTimeToEmpty( )
D AtRateTimeToFull( )
D RunTimeToEmpty( )
D AverageTimeToEmpty( )
D AverageTimeToFull( )
D Remaining Time Alarm( )
D BatteryStatus( )
The bq2083−V1P3 updates the non-AtRate related register values within 1 s of changing the state of the
CAPACITY_MODE bit. The AtRate( ) values are updated after the next AtRate value is written to the
bq2083−V1P3 (or after the next 1 s scheduled refresh calculation).
AtRate( ) (0x04)
Description: The AtRate( ) function is the first half of a two-function call-set used to set the AtRate value used
in calculations made by the AtRateTimeToFull( ), AtRateTimeToEmpty( ), and AtRateOK( ) functions. The AtRate
value may be expressed in either current (mA) or power (10 mW) depending on the setting of the BatteryMode( )
CAPACITY_MODE bit.
Purpose: Since the AtRate( ) function is the first half of a two-function call-set, it is followed by the second function
of the call-set that calculates and returns a value based on the AtRate value and the battery’s present state.
D When the AtRate( ) value is positive, the AtRateTimeToFull( ) function returns the predicted time to full-charge
at the AtRate value of charge.
D When the AtRate( ) value is negative, the AtRateTimeToEmpty( ) function returns the predicted operating time
at the AtRate value of discharge.
D When the AtRate( ) value is negative, the AtRateOK( ) function returns a boolean value that predicts the
battery’s ability to supply the AtRate value of additional discharge energy (current or power) for 10 seconds.
The default value for AtRate( ) is zero.
SMBus protocol: Read or write word
Input/Output: Signed integer-charge or discharge; the AtRate( ) value is positive for charge, negative for
discharge, and zero for neither (default).
Units
Charge range
Discharge range
Granularity
Accuracy
BATTERY MODES
CAPACITY_MODE
BIT = 0
CAPACITY_MODE
BIT = 1
mA
10 mW
1 to 32,767 mA
1 to 32,767 10 mW
−1 to −32,768 mA
−1 to −32,768 10 mW
1 Unit
NA
AtRateTimeToFull( ) (0x05)
Description: Returns the predicted remaining time to fully charge the battery at the AtRate( ) value (mA).
Purpose: The AtRateTimeToFull( ) function is part of a two-function call-set used to determine the predicted
remaining charge time at the AtRate value in mA. The bq2083−V1P3 updates AtRateTimeToFull( ) within 5 ms
after the SMBus host sets the AtRate value. The bq2083−V1P3 automatically updates AtRateTimeToFull( ) based
on the AtRate( ) value every 1 s.
SMBus protocol: Read word
Output: Unsigned integerpredicted time in minutes to fully charge the battery.
Units: Minutes
26