BQ24100 Datasheet, PDF (16/26 Pages) Texas Instruments – SYNCHRONOUS SWITCHMODE, LI-ION AND LI-POL CHARGE MANAGEMENT IC WITH INTEGRATED POWERFETS

bq24100, bq24103
bq24105, bq24108
bq24113, bq24115
SLUS606C – JUNE 2004 – REVISED SEPTEMBER 2005
www.ti.com
FUNCTIONAL DESCRIPTION FOR STAND-ALONE VERSION (bq2410x) (continued)
A new charge cycle is initiated when one of the following conditions is detected:
• The battery voltage falls below the V_RCH threshold.
• Power-on reset (POR), if battery voltage is below the V_RCH threshold
• CE toggle
• TTC pin, described as follows.
In order to disable the charge termination and safety timer, the user can pull the TTC input below the V_{TTC_EN}
threshold. Going above this threshold enables the termination and safety timer features and also resets the timer.
Tying TTC high to VTSB disables the safety timer only.
Sleep Mode
The bqSWITCHER enters the low-power sleep mode if the VCC pin is removed from the circuit. This feature
prevents draining the battery during the absence of VCC.
Charge Status Outputs
The open-drain STAT1 and STAT2 outputs indicate various charger operations as shown in Table 1 and Table 2.
These status pins can be used to drive LEDs or communicate to the host processor. Note that OFF indicates that
the open-drain transistor is turned off.
Table 1. Status Pins Summary
Charge State
Charge-in-progress
Charge complete
Charge suspend, timer fault, overvoltage, sleep mode, battery absent⁽¹⁾
(1) bq2411x ICs do not have timer-fault or battery-absent modes
STAT1
ON
OFF
OFF
Table 2. Status Pins Summary (bq24108 only)
Charge State
Battery absent
Charge-in-progress
Charge complete
Battery over discharge, V_I(BAT) < V_(SC)
Charge suspend, (due to TS pin and internal thermal protection)
Precharge timer fault
Fast-charge timer fault
Sleep mode
STAT1
OFF
ON
OFF
ON/OFF (0.5 Hz)
ON/OFF (0.5 Hz)
ON/OFF (0.5 Hz)
ON/OFF (0.5 Hz)
OFF
STAT2
OFF
ON
OFF
STAT2
OFF
OFF
ON
OFF
OFF
OFF
OFF
OFF
PG Output
The open-drain PG (power good) indicates when the AC-to-DC adapter (i.e., V_CC) is present. The output turns on
when sleep-mode exit threshold, V_SLP-EXIT, is detected. This output is turned off in the sleep mode. The PG pin
can be used to drive an LED or communicate to the host processor.
CE Input (Charge Enable)
The CE digital input is used to disable or enable the charge process. A low-level signal on this pin enables the
charge and a high-level V_CC signal disables the charge. A high-to-low transition on this pin also resets all timers
and fault conditions. Note that the CE pin cannot be pulled up to VTSB voltage. This may create power-up
issues.
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