MAX17050EVKIT# Maxim Integrated, MAX17050EVKIT# Datasheet - Page 10

• Manufacturer Part Number: MAX17050EVKIT#
• Description: Power Management IC Development Tools MAX17050 Eval Kit
• Manufacturer: Maxim Integrated
• Type: Voltage Protectionr
• Series: MAX17047, MAX17050r

Specifications of MAX17050EVKIT#

• Rohs: yes
• Product: Evaluation Kits
• Tool Is For Evaluation Of: MAX17050
• Input Voltage: 2.5 V to 4.5 V
• Interface Type: I2C
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Part # Aliases: 90-BT07K#D00
• For Use With: MAX17050

The core of the ModelGauge m3 algorithm is a mixing
algorithm that combines the OCV state estimation with
the coulomb counter. After power-on reset of the IC,
coulomb-count accuracy is unknown. The OCV state
estimation is weighted heavily compared to the coulomb-
count output. As the cell progresses through cycles in
the application, coulomb-counter accuracy improves
and the mixing algorithm alters the weighting so that
the coulomb-counter result is dominant. From this point
forward, the IC switches to servo mixing. Servo mixing
provides a fixed magnitude continuous error correction to
the coulomb count, up or down, based on the direction
of error from the OCV estimation. This allows differences
between the coulomb count and OCV estimation to be
corrected quickly. See
Figure 3. ModelGauge m3 OCV and Coulomb-Count Mixing
Figure 4. ModelGauge m3 Algorithm Mixing Conceptual Illustration
Maxim Integrated
OCV Estimation and Coulomb-Count Mixing
100%
0%
0
INFLUENCE
OCV
0.50
COULOMB-COUNT INFLUENCE
CELL CYCLES
Figure
1.00
3.
1.50
ERROR AS CELL IS CYCLED
2.00
TYPICAL OCV ESTIMATION
SERVO MIXING
ModelGauge m3 Fuel Gauge
TIME
OCV + COULOMB-COUNT MIXING
The resulting output from the mixing algorithm does
not suffer drift from current measurement offset error
and is more stable than a stand-alone OCV estimation
algorithm; see
relaxation state of the cell. The highest initial accuracy is
achieved with a fully relaxed cell.
As the temperature and discharge rate of an applica-
tion changes, the amount of charge available to the
applica tion also changes. The ModelGauge m3 algo-
rithm dis tinguishes between remaining capacity of the
cell (RemCap
cation (RemCap
The device periodically makes internal adjustments
to cell characterization and application information to
remove initial error and maintain accuracy as the cell
ages. These adjustments always occur as small under-
corrections to prevent instability of the system and
prevent any noticeable jumps in the fuel-gauge outputs.
Learning occurs automatically without any input from the
host. To maintain learned accuracy through power loss,
the host must periodically save learned information and
then restore after power is returned. See the
and Power-On Reset
• Full Capacity Available to Application (FullCAP).
MAXIMUM ERROR RANGE
(SHADED AREA)
ModelGauge m3
This is the total capacity available to the application
at full. FullCAP is updated near the end of charging
when termination is detected. See the
Detection
MAX17047/MAX17050
MAXIMUM COULOMB-COUNTER ERROR
section.
MIX
Fuel-Gauge Empty Compensation
Figure
AV
) and remaining capacity of the appli-
) and reports both results to the user.
section for details:
4. Initial accuracy depends on the
Fuel-Gauge Learning
End-of-Charge
Power-Up
10