Hi
I'm usign the BQ27210 to monitor the battery charge of a custom device we're developing, but we're having some problems related to the BQ27210 operation. According to the datasheet, I can see the following expected behaviour:
PAGE 11: Gas Gauge Operation;
NAC is adjusted by charge and discharge coulometric measurements except when battery full or empty
conditions are detected. NAC = LMD is forced when IMIN = 1 (full detection) unless Temperature ≤
TCOMP[2:0]*2 (°C)
PAGE 15: Status Flag Register (FLAGS):
IMIN: Li-ion taper current detection flag. A 1 indicates that the charge current has tapered to less than
the value set in EEPROM and that the battery voltage is greater than or equal to the value
selected by the QV0 and QV1 bits in the PKCFG register (see EEPROM Data Register description
for more details). Taper current detection is disqualified if AI < 8 (28.6 µV across sense resistor).
The taper detection conditions must be maintained for 4 successive average current
measurements (20-25 s) to qualify as a valid taper current detection. This bit is cleared to 0 on all
resets.
According to this, when battery is charged at full capacity, the charging current will drop below TAPER current, and this condition is detected as full charged, so NAC will be forced to LMD. My problem is the IMIN flag is never set. I've been monitoring the AI register in order to know how much current is entering into the battery, and I can see its value is below the TAPER current value, but the IMIN flag is never set.
What coud be happening? Any suggestion would be appreciated.
Regards,
Eduardo
