BQ2050_15 Datasheet, PDF (8/27 Pages) Texas Instruments – Lithium Ion Power Gauge™ IC

Not Recommended For New Designs
bq2050
Table 3A. Graphite Anode
Approximate
Discharge Rate
< 0.5C
≥ 0.5C
Discharge
Compensation
Factor
1.00
1.05
Efficiency
100%
95%
Table 3B. Graphite Anode
Temperature
≥ 10°C
0°C to 10°C
-10°C to 0°C
≤ -10°C
Temperature
Compensation
Factor
1.00
1.10
1.35
2.50
Efficiency
100%
90%
74%
40%
Table 4A. Coke Anode
Approximate
Discharge Rate
<0.5C
≥ 0.5C
Discharge
Compensation
Factor
1.00
1.15
Efficiency
100%
86%
Table 4B. Coke Anode
Temperature
≥ 10°C
0°C to 10°C
-10°C to 0°C
≤ -10°C
Temperature
Compensation
Factor
1.00
1.25
2.00
8.00
Efficiency
100%
80%
50%
12%
Charge Compensation
The bq2050 applies the following temperature compen-
sation to NAC during charge:
Temperature
Temperature
Compensation
Factor
Efficiency
< 10°C
0.95
95%
≥ 10°C
1.00
100%
This compensation applies to both types of Li-Ion cells.
Self-Discharge Compensation
The self-discharge compensation is programmed for a
nominal
rate
of
1
512
*
NAC
per
day.
This is the rate for a
battery within the 20°C–30°C temperature range. This
rate varies across 8 ranges from < 10°C to > 70°C, chang-
ing with each higher temperature (approximately 10°C).
See Table 5 below:
Table 5. Self-Discharge Compensation
Temperature Range
< 10°C
10–20°C
20–30°C
30–40°C
40–50°C
50–60°C
60–70°C
> 70°C
Typical Rate
PROG5 = Z or L
NAC
2048
NAC
1024
NAC
512
NAC
256
NAC
128
NAC
64
NAC
32
NAC
16
Self-discharge may be disabled by connecting PROG5 = H.
Digital Magnitude Filter
The bq2050 has a digital filter to eliminate charge and dis-
charge counting below a set threshold. The bq2050 setting
is 200µV for VSRD and 210µV for VSRQ.
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