BQ2092_15 Datasheet, PDF (21/30 Pages) Texas Instruments – Gas Gauge IC with SMBus-Like Interface

Obsolete Device
bq2092
Table 9. Example Register Contents (Continued)
Description
EEPROM
Address
Low High
Byte Byte
EEPROM
Hex
Contents
Low High
Byte Byte
Temperature
Offset¹
0x12
32
Example
Values
5.0°C
Notes
The default value is 0x80 (12.8° + nominal value).
Actual temp (20°C) = Nominal temp. (15°C) - temp.
offset (5°C) where temperature determined by the
bq2092 can be adjusted from 0° to 25.5° (Tempera-
ture offset (0-255) ∗ 0 .1) + nominal value temp.
Maximum
Charge
Temperature,
0x13
87
∆Temp.
Self-
Discharge Rate
0x14
dd
Digital
Filter
0x15
96
Current
Integration
Gain¹
0x16 0x17 40
Full Charge
Percentage
0x18
a0
Charge
Compensation
0x19
bd
Battery
Voltage
Offset¹
(VOFF)
Voltage
Gain¹
Serial
Number
0x1a
0a
0x1b 0x1c 09
0x1d 0x1e 12
MaxT = 61.2°C
(74 - (8 * 1.6))
∆T = 3°C
((7*2) + 16)/10
Maximum charge temperature is 74 - (mt x 1.6)°C
(mt = upper nibble). The ∆T step is (dT*2+16)/10°C
(dT = lower nibble).
1.5%
This packed field is the two's complement of
52.73/x, where x = %/day is the self-discharge rate
desired at room temperature.
0.3mV
This field is used to set the digital magnitude filter
as described in Table 2.
This field represents the following: 3.2/sense resis-
tor in ohms. It is used by the bq2092 to scale the
00
3.2/0.05
measured voltage values on the SR pin in mA and
mAh. This register also compensates for variations
in the reported sense resistor value.
96% = 60h
2’s (60h) = a0h
This packed field is the two’s complement of the
desired value in RM when the bq2092 determines
a full charge termination. If RM is below this
value, RM is set to this value. If RM is above this
value, then RM is not adjusted.
This packed value is used to set the fast charge and
85% = mainte-
nance comp.
95% = fast
charge comp.
maintenance charge efficiency for nickel-based batter-
ies. The upper nibble adjusts the maintenance charge
compensation; the lower nibble adjusts the fast
charge compensation.
Maintenance, upper nibble = (eff% ∗ 256 - 128)/8
Fast charge, lower nibble = (eff% ∗ 256 - 192)/4
10mV
This value is used to adjust the battery voltage offset
according to the following:
Voltage () = (VSB (mV) + VOFF) ∗ Voltage Gain
Voltage gain is packed as two units. For example,
17
9.09
(R4 + R5)/R4 = 9.09 would be stored as: whole num-
ber stored in 0x1b (=09h) and the decimal compo-
nent stored in 0x1c as 256 x 0.09 = 23.
27
10002
This contains the optional pack serial number.
21