BQ2060SS Datasheet, PDF (46/59 Pages) Texas Instruments – SBS V1.1-COMPLIANT GAS GAUGE IC

bq2060
SLUS035E – JANUARY 2000 – REVISED OCTOBER 2005
www.ti.com
EEPROM PROGRAMMING (continued)
∆T/ ∆t Rate Programming
The ∆T portion of the ∆T/∆t rate is programmed in DeltaT, the low nibble of MaxT DeltaT EE 0x45 (least
significant nibble). The ∆t portion is programmed in DeltaT Time EE 0x4e.
ƪ ƫ DTńDt
+
[DeltaT 2
[320 * DeltaT
) 16]ń10
Time 20]
°C
s
(22)
DeltaT
∆ (°C)
DeltaT_Time
t (s)
0
1.6
00
320
1
1.8
01
300
2
2.0
02
280
3
2.2
03
260
4
2.4
04
240
5
2.6
05
220
6
2.8
06
200
7
3.0
07
180
8
3.2
08
160
9
3.4
09
140
a
3.6
0a
120
b
3.8
0b
100
c
4.0
0c
80
d
4.2
0d
60
e
4.4
0e
40
f
4.6
0f
20
∆T/ ∆t Holdoff Timer Programming
The holdoff timer is programmed in the lower nibble of Holdoff Time EE 0x4f. The holdoff time is 320 s minus 20
times the Holdoff Time value.
Holdoff
Time
00
01
02
03
04
05
06
07
Holdoff
Time (s)
320
300
280
260
240
220
200
180
Holdoff
Time
08
09
0a
0b
0c
0d
0e
0f
Holdoff
Time (s)
160
140
120
100
80
60
40
20
Current Taper Termination Characteristics
Two factors in the EEPROM set the current taper termination for Li-ion battery packs. The two coded locations
are Current Taper Qual Voltage EE 0x4f and Current Taper Threshold EE 0x4e. Current taper termination occurs
during charging when the pack voltage is above the charging voltage minus CELLV (mV) and the charging
current is below the threshold coded in Current Taper Threshold for at least 40 s.
Current
Taper
Qual
Voltage
+
CELLV
2
(23)
Current
TaperThreshhold
+
R_s i
0.5625
(24)
where i = the desired current termination threshold in mA, and R_S = VFC sense resistor in ohms.
46