Datasheet

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 =
C
64
Voltage drop over sense resistor = 5mV to 400mV
Therefore:
2200mAh ∗ 0.1
Ω
= 220mVh
Select:
PFC = 33792 counts or 211mVh
PROG
1
= float
PROG
2
= float
PROG
3
= float
PROG
4
= low
PROG
5
= float
DONE = low
6
bq2014
PROG
x
Programmed
Full
Count
(PFC)
PROG
4
= L PROG
4
= Z
Units
1 2 PROG3 = H PROG3 = Z PROG3 = L PROG3 = H PROG3 = Z PROG3 = L
-- -
Scale =
1/80
Scale =
1/160
Scale =
1/320
Scale =
1/640
Scale =
1/1280
Scale =
1/2560
mVh/
count
H H 49152 614 307 154 76.8 38.4 19.2 mVh
H Z 45056 563 282 141 70.4 35.2 17.6 mVh
H L 40960 512 256 128 64.0 32.0 16.0 mVh
Z H 36864 461 230 115 57.6 28.8 14.4 mVh
Z Z 33792 422 211 106 53.0 26.4 13.2 mVh
Z L 30720 384 192 96.0 48.0 24.0 12.0 mVh
L H 27648 346 173 86.4 43.2 21.6 10.8 mVh
L Z 25600 320 160 80.0 40.0 20.0 10.0 mVh
L L 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
Table 2. bq2014 Programmed Full Count mVh Selections
Pin Connection PROG
5
Self-Discharge Rate DISP Display State
H Disabled LED disabled
Z
NAC
64
LED enabled on discharge when
V
SRO
< -4mV or during a valid charge
L
NAC
47
LED on
Table 1. bq2014 Programming