BQ2013H Datasheet, PDF (13/24 Pages) Texas Instruments – Gas Gauge IC for Power- Assist Applications

bq2013H
Table 10. Temperature Register Contents
TMP3 TMP2 TMP1 TMP0 Temperature
0
0
0
0
T < -30°C
0
0
0
1 -30°C < T < -20°C
0
0
1
0 -20°C < T < -10°C
0
0
1
1
-10°C < T < 0°C
0
1
0
0
0°C < T < 10°C
0
1
0
1
10°C < T < 20°C
0
1
1
0
20°C < T < 30°C
0
1
1
1
30°C < T < 40°C
1
0
0
0
40°C < T < 50°C
1
0
0
1
50°C < T < 60°C
1
0
1
0
60°C < T < 70°C
1
0
1
1
70°C < T < 80°C
1
1
0
0
T > 80°C
Temperature and Gas Gauge Register
(TMPGG)
TMPGG Temperature Bits
7
6
5
4
3210
TMP3 TMP2 TMP1 TMP0 - - -
The read-only TMPGG register (address=02h) contains
two data fields. The first field contains the battery tem-
perature. The second field contains the available charge
from the battery.
The bq2013H contains an internal temperature sensor.
The temperature is used to set charge efficiency factors
as well as to adjust the self-discharge coefficient. The
temperature register contents may be translated as
shown in Table 10.
The bq2013H calculates the available charge as a func-
tion of NAC and a full reference, either LMD or PFC.
The results of the calculation are available via the dis-
play port or the gas gauge field of the TMPGG register.
The
register
is
used
to
give
available
capacity
in
1
16
in-
crements from 0 to ¹⁵¹⁶.
TMPGG Gas Gauge Bits
7 65 4
3
2
1
0
-
--
- GG3 GG2 GG1 GG0
Nominal Available Charge Register (NAC)
The NACH register (address=03h) and the NACL regis-
ter (address=17h) are the main gas gauging registers for
the bq2013H. The NAC registers are incremented dur-
ing charge actions and decremented during discharge
and self-discharge actions. The correction factors for
charge/discharge efficiency are applied automatically to
NAC. NACH and NACL are set to 0 during a bq2013H
reset.
Battery Identification Register (BATID)
The read/write BATID register (address=04h) is avail-
able for use by the system to determine the type of bat-
tery pack. The BATID contents are retained as long as
V_RBI is greater than 2V. The contents of BATID have no
effect on the operation of the bq2013H. There is no de-
fault setting for this register.
Last Measured Discharge Register (LMD)
LMD is a read/write register (address=05h) that the
bq2013H uses as a measured full reference. The
bq2013H adjusts LMD based on the measured discharge
capacity of the battery from full to empty. In this way
the bq2013H updates the capacity of the battery. LMD
is set to PFC during a bq2013H reset.
Secondary Status Flags Register (FLGS2)
The read-only FLGS2 register (address=06h) contains
the secondary bq2013H flags.
The charge rate flag (CR) is used to denote the fast
charge regime. Fast charge is assumed whenever a
charge action is initiated. The CR flag remains asserted
if the charge rate does not fall below 2 NAC counts/s.
The CR location is:
FLGS2 Bits
7
65
4
3
2
1
0
CR - -
-
-
-
-
-
Where CR is:
0 When charge rate falls below 2 counts/sec
1 When charge rate is above 2 counts/sec
The fast charge regime efficiency factors are used when
CR = 1. When CR = 0, the trickle charge efficiency fac-
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