Datasheet

PORorRECHARGE
Enable 125mA Charge,
Start 0.5stimer
VFB > V
RECH
No
BatteryPresent,
BeginCharge
0.5stimer
expired
Yes
No
Yes
Disable 125mA
Charge
Apply 8mA discharge
current, start 1stimer
VFB < V
LOWV
No
BatteryPresent,
BeginCharge
1stimer
expired
Yes
No
Yes
Disable 8mA
dischargecurrent
Thebatterydetectionroutinerunson
powerup, orifVFBfallsbelowVRECH
duetoremovingabatteryor
dischargingabattery
Battery Absent
bq24600
SLUS891A –FEBRUARY 2010– REVISED OCTOBER 2011 www.ti.com
Battery Detection
For applications with removable battery packs, bq24600 provides a battery-absent detection scheme to reliably
detect insertion or removal of battery packs. CE must be HIGH to enable the battery-detection function.
Figure 16. Battery Detection Flowchart
Once the device has powered up, an 8-mA discharge current is applied to the SRN terminal. If the battery
voltage falls below the LOWV threshold within 1 second, the discharge source is turned off, and the charger is
turned on at low charge current (125 mA). If the battery voltage rises above the recharge threshold within 500
ms, no battery is present and the cycle restarts. If either the 500-ms or 1-second timer times out before the
respective thresholds are hit, a battery is detected and a charge cycle is initiated.
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Product Folder Link(s): bq24600