BQ2014_15 Datasheet, PDF (6/27 Pages) Texas Instruments – Gas Gauge IC with External Charge Control

Not Recommended For New Designs
bq2014
determined by multiplying the rated battery capac-
ity in mAh by the sense resistor value:
Battery capacity (mAh) _* sense resistor (Ω) =
PFC (mVh)
Selecting a PFC slightly less than the rated capac-
ity for absolute mode provides capacity above the
full reference for much of the battery's life.
Example: Selecting a PFC Value
Given:
Sense resistor = 0.1Ω
Number of cells = 6
Capacity = 2200mAh, NiCd battery
Current range = 50mA to 2A
Relative display mode
Serial port only
Self-discharge = ^C64
Voltage drop over sense resistor = 5mV to 400mV
Therefore:
2200mAh ∗ 0.1Ω = 220mVh
Select:
PFC = 33792 counts or 211mVh
PROG1 = float
PROG2 = float
PROG3 = float
PROG4 = low
PROG5 = float
DONE = low
Pin Connection
H
Z
L
Table 1. bq2014 Programming
PROG5 Self-Discharge Rate
Disabled
NAC
64
NAC
47
DISP Display State
LED disabled
LED enabled on discharge when
VSRO < -4mV or during a valid charge
LED on
Table 2. bq2014 Programmed Full Count mVh Selections
PROGx
12
Programmed
Full
Count
(PFC)
PROG3 = H
PROG4 = L
PROG3 = Z
PROG3 = L
PROG3 = H
PROG4 = Z
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
HH
49152
614
307
154
76.8
38.4
19.2
mVh
HZ
45056
563
282
141
70.4
35.2
17.6
mVh
HL
40960
512
256
128
64.0
32.0
16.0
mVh
ZH
36864
461
230
115
57.6
28.8
14.4
mVh
ZZ
33792
422
211
106
53.0
26.4
13.2
mVh
ZL
30720
384
192
96.0
48.0
24.0
12.0
mVh
LH
27648
346
173
86.4
43.2
21.6
10.8
mVh
LZ
25600
320
160
80.0
40.0
20.0
10.0
mVh
LL
22528
282
141
70.4
35.2
17.6
8.8
mVh
VSR equivalent to 2
counts/s (nom.)
90
45
22.5
11.25
5.6
2.8
mV
6