Datasheet

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bq20z80-V102
SLUS681B – NOVEMBER 2005 – REVISED JANUARY 2007
CHANGE bq20z80 bq20z80-V101 COMMENTS
Improved thermal model A preliminary thermal mode was An updated thermal model is used. Improved thermal compensation of
used. Impedance Track™ algorithm
Improved cell capacity measurement Valid voltage measurements for cell Valid voltage measurements for cell Improves capacity estimation
by limiting valid temperature ranges capacity estimation can occur at any capacity estimation must occur within
temperature. a defined temperature range.
Improved cell capacity measurement After a full reset, it may take several Settling time of voltage Improves initial voltage reading
minutes for voltage reading to settle measurements after a full reset is accuracy
to the most accurate reading. reduced.
Improved default resistance tables A preliminary default resistance mode An updated default resistance mode Improved thermal accuracy of
was used. is used. Impedance Track™ algorithm
Prevented lifetime updates until IT is Data flash lifetime data is updated Data flash lifetime data is not updated Improves suitability of lifetime data
enabled under all conditions. until Impedance Track™ is enabled.
Aligned SBS.RemainingCapacity( ) SBS.RemainingCapacity( ) could be Forces SBS.RemainingCapacity( ) to Improves alignment between
with DF:Terminate Voltage above zero when SBS.Voltage( ) zero when SBS.Voltage( ) is below reporting and system status
reaches DF:Terminate Voltage. terminate voltage
Disabled LEDs for undervoltage When SBS.OperationStatus( ) [CUV When SBS.OperationStatus( ) [CUV Reduces risk of deeply discharging
conditions or PUV] is set, then the LED display or PUV] is set, the LED display is the battery
could be activated. disabled.
Clear SBS.BatteryStatus( ) [RCA] SBS.BatteryStatus( ) [RCA] is not SBS.BatteryStatus( ) [RCA] is now Corrected to meet SBS specification
when not SBS.BatteryStatus( ) [DSG] cleared when SBS.BatteryStatus( ) cleared when SBS.BatteryStatus( )
[DSG] is cleared. [DSG] is cleared.
Allowed sleep mode for undervoltage When SBS.OperationStatus( ) [CUV When SBS.OperationStatus( ) [CUV Reduces risk of deeply discharging
conditions or PUV] is set, then entry to sleep or PUV] is set, then entry to sleep the battery
mode is disabled. mode is allowed.
Improvements made to Lifetime data Does not save maximum and Saves maximum and minimum Improves lifetime data
minimum lifetime AverageCurrent or lifetime AverageCurrent and
AveragePower. Only saves lifetime AveragePower. Lifetime data is saved
data when new values exceed old after a defined period of time even if
values by defined delta values new values do not exceed old values
by defined delta values
Changes made to pulse charging Voltages for pulse charging are Voltages for pulse charging are Improves pulse charging
sampled once a second. sampled 4 times a second.
Changes made to charging timeouts The precharge timeout timer runs The fast charge and precharge Improves operation of fast charge and
when the charging current is below a timeout timers only run when precharge timeout timers
defined threshold; so, it is possible precharging or charging, as indicated
that the precharge timer will run by FCHG and PCHG bits in
during charging taper current and ChargingStatus.
cause an undesired precharge
timeout during charging taper.
Changes made to discharge faults Discharging fault is indicated Discharging fault is indicated for any Improves indication of discharging
whenever BatteryStatus [TDA] is set. safety condition resulting in turning off fault conditions
Current discharging fault is not the discharge FET. Current
indicated for current faults detect by discharging fault is indicated for all
AFE. Separate discharging faults are detected overcurrent conditions,
indicated for voltage and temperature. including overcurrent detected by
AFE. Temperature and voltage
discharge faults are not indicated
separately.
Improvements made to calibration Voltage calibration functions may Voltage calibration functions are Improved voltage calibration accuracy
functions cause error in voltage calibration of capable of accuracy within 1 millivolt.
several millivolts.
Protect against simultaneous writes to A SMBus-initiated data flash write A SMBus-initiated data flash write Increased robustness of data flash
data flash may occur at the same time as a data cannot occur at the same time as any writes
flash write initiated by the AGG, which other data flash write.
my cause a data flash write error.
Corrected SBS.ManufacturerAccess( ) access of SBS.ManufacturerAccess( ) access of Allows host to determine bq20z80
SBS.ManufacturerAccess( ) access of silicon revision is not functional. silicon revision is functional. silicon revision
silicon revision
Corrected data flash checksum The data flash checksum includes The data flash checksum only Data flash checksum operation works
operation non-accessible portions of the data includes data flash that does not correctly.
flash that change when writing the change when writing an updated data
data flash checksum, invalidating the flash checksum.
checksum.
Corrections made to LED display Fixed LED thresholds cannot be Fixed LED thresholds can be Correct operation of LED threshold
selected. selected. settings
Erroneous readings are corrected that Erroneous SBS voltage, current, and No erroneous SBS voltage, current, Improve reliability of lifetime data
occurred after offset calibration when temperature readings occur after and temperature readings occur after
sleep mode is not entered. current offset calibration if sleep mode current offset calibration if sleep mode
is not entered, corrupting the lifetime is not entered.
data.
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