BQ2010_15 Datasheet, PDF (6/26 Pages) Texas Instruments – Gas Gauge IC

Not Recommended For New Designs
bq2010
Example: Selecting a PFC Value
Select:
Given:
Sense resistor = 0.1Ω
Number of cells = 6
Capacity = 2200mAh, NiCd battery
Current range = 50mA to 2A
Absolute display mode
Serial port only
Self-discharge = ^C ₆₄
Voltage drop over sense resistor = 5mV to 200mV
Therefore:
PFC = 33792 counts or 211mVh
PROG₁ = float
PROG₂ = float
PROG₃ = float
PROG₄ = low
PROG₅ = float
PROG₆ = float
The initial full battery capacity is 211mVh
(2110mAh) until the bq2010 “learns” a new capac-
ity with a qualified discharge from full to EDV1.
2200mAh _* 0.1Ω = 220mVh
Table 1. bq2010 Programming
Pin
Connection
H
Z
L
PROG₅
Self-Discharge Rate
Disabled
NAC
64
NAC
47
PROG₆
Display Mode
Absolute
NAC = PFC on reset
Absolute
NAC = 0 on reset
Relative
NAC = 0 on reset
Note:
PROG₅ and PROG₆ states are independent.
DISP
Display State
LED disabled
LED-enabled on discharge or charge
when equivalent |V_SRO| ≥ 4mV
LED on
Table 2. bq2010 Programmed Full Count mVh Selections
PROG_x
12
Pro-
grammed
Full
Count
(PFC)
--
-
HH
49152
HZ
45056
HL
40960
ZH
36864
ZZ
33792
ZL
30720
LH
27648
LZ
25600
LL
22528
VSR equivalent to 2
counts/sec. (nom.)
PROG₄ = L
PROG₄ = Z
PROG3 = H PROG3 = Z PROG3 = L PROG3 = H PROG3 = Z PROG3 = L Units
Scale =
1/80
Scale =
1/160
Scale =
1/320
Scale =
1/640
Scale =
1/1280
Scale =
1/2560
mVh/
count
614
307
154
76.8
38.4
19.2
mVh
563
282
141
70.4
35.2
17.6
mVh
512
256
128
64.0
32.0
16.0
mVh
461
230
115
57.6
28.8
14.4
mVh
422
211
106
53.0
26.4
13.2
mVh
384
192
96.0
48.0
24.0
12.0
mVh
346
173
86.4
43.2
21.6
10.8
mVh
320
160
80.0
40.0
20.0
10.0
mVh
282
141
70.4
35.2
17.6
8.8
mVh
90
45
22.5
11.25
5.6
2.8
mV
6