Exp: 8-bit exponent stored with an offset bias of 127. The values 00 and FF have special meaning.
Fract: 23-bit fraction. If the exponent is > 0, then the mantissa is 1.fract. If the exponent is zero, then the
mantissa is 0.fract.
The floating point value depends on the special cases of the exponent:
• If the exponent is FF and the fraction is zero, this repr/– infinity.
• If the exponent is FF and the fraction is non-zero this represents "not a number" (NaN).
• If the exponent is 00 then the value is a subnormal number represented by (–1)
sign
× 2
–126
× 0.fraction.
• Otherwise, the value is a normalized number represented by (–1)
sign
× 2
(exponent – 127)
× 1.fraction.
13.1.4 Hex
Bit register definitions are stored in unsigned integer format.
13.1.5 String
String values are stored with length byte first, followed by a number of data bytes defined with the length byte.
0
1
. . .
N
Length
Data0
. . .
DataN
13.2 Calibration
13.2.1 Voltage
Class
Subclass
Name
Type
Min
Max
Default
Unit
Description
Calibration
Voltage
Cell Gain
I2
–32768
32767
12101
—
VC[n]–VC[n–1] gain
Calibration
Voltage
PACK Gain
U2
0
65535
49669
—
PACK–VSS gain
Calibration
Voltage
VC2 (BAT) Gain
U2
0
65535
48936
—
VC2 (BAT)–VSS gain
(1)
Setting this value to 0 causes the gauge to use the internal factory calibration default.
13.2.2 Current
Class
Subclass
Name
Type
Min
Max
Default
Description
Calibration
Current
CC Gain
F4
1.00E–001
4.00E+000
3.58422
Coulomb Counter Gain
Calibration
Current
Capacity Gain
F4
2.98E+004
1.19E+006
106903.5
Capacity Gain
13.2.3 Current Offset
Class
Subclass
Name
Type
Min
Max
Default
Unit
Description
Calibration
Current Offset
CC Offset
I2
–32768
32767
0
—
Coulomb Counter Offset
Calibration
Current Offset
Coulomb Counter
Offset Samples
U2
0
65535
64
—
Coulomb Counter Offset Samples used for
averaging
Calibration
Current Offset
Board Offset
I2
–32768
32767
0
—
PCB board offset
Calibration
Current Offset
CC Auto Config
H1
00
07
03
hex
Bit 0: AUTO_CAL_EN: Auto
CC Offset
calibration
enable
0 = Disabled Auto CC calibration offset
1 = Firmware will perform auto CC calibration on
entry into SLEEP mode. A min auto CC calibration
interval is set to 10 hrs to prevent false wear out.
The result is saved to
CC Auto Offset
.
Bit 1: AUTO_NESTON: NEST Circuit ON
0 = HW NEST circuit is always on. Individual cell
current measurement may have an error relative
to
Current()
, but the
Current()
accuracy is not
impacted.
1 = When
[OFFSET_TAKEN]
= 1, FW
automatically controls the HW NEST circuit for best
current and cell current measurements.
Bit 2: OFFSET_TAKEN:
CC Auto Offset
is taken.
0 =
CC Auto Offset
has not been measured.
1 =
CC Auto Offset
has been measured.
Bit 3 to Bit 7: Reserved
Calibration
Current Offset
CC Auto Offset
I2
–10000
10000
0
CC Offset
collected via
CC Auto Calibration
.
Used for cell current measurement and is different
than
CC Offset
.
Data Flash Values
96
BQ28Z610-R2
Copyright © 2022 Texas Instruments Incorporated
