BQ26501_16 Datasheet, PDF (16/33 Pages) Texas Instruments – HANDHELD APPLICATIONS

bq26501
Not Recommended For New Designs
ą
SLUS586B − OCTOBER 2003 − REVISED MARCH 2004
APPLICATION INFORMATION
Initial Last Measured Discharge High Byte (ILMD) – Address 0x76
This register contains the scaled design capacity of the battery to be monitored. The equation to calculate the
initial LMD is:
Design Capacity (mAh)
ILMD +
(256 3 mVh)
R_S(mW)
(4)
where R_S is the value of the sense resistor used in the system. This value is used as the high byte for the initial
LMD values. The initial low byte value is “0”.
Scaled EDVF Threshold (SEDVF) – Address 0x77
This register contains the scaled value of the threshold for zero battery capacity. To calculate the value to
program, use the following equation:
SEDVF
+
Design
EDVF
8
(mV)
*
256
(5)
Scaled EDV1 Threshold (SEDV1) – Address 0x78
This register contains the scaled value of the voltage when the battery has 6.25% remaining capacity. When
the battery reaches this threshold during a valid discharge, the device learns the full battery capacity, including
the remaining 6.25%. To calculate the value to program, use the following equation:
SEDV1
+
Design
EDV1
8
(mV)
*
256
(6)
Initial Standby Load Current (ISLC) – Address 0x79
This register contains the scaled end equipment design standby current. A capacity learning cycle is disqualified
if average current is less than or equal to two times the initial standby load when the EDV1 threshold voltage
is reached. The equation for programming this value is:
Design Standby Current (mA)
ISLC +
6 (mV)
R_S (mW)
(7)
where R_S is the value of the sense resistor used in the system.
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