ACT2801/ACT2801C
Rev 2, 15-Apr-14
programmed by a resistor connected from BLVS
pin to AGND as shown in Figure 6. The following
equation shows the LED4 voltage threshold:
APPLICATIONS INFORMATION
Battery Charge Termination Voltage
VBATLED4(V ) = 3.5(V ) + 0.01(mA)× RBLVS(kΩ )
(2)
Battery charge termination voltage is set by a
resistor Rbtv connected from BTV pin to AGND as
shown in Figure 5. The battery charge termination
voltage is estimated as the following equation:
VBAT (V ) = 4.1(V ) + Rbtv ×4 ×10−6(V )
(1)
Rbtv is selected based on the battery voltage rating.
1% accuracy resistor is recommended for Rbtv.
Figure 6. Battery level voltage shift setting circuit
As long as LED4 is set, all the other 3 LED
thresholds is fixed as shown in the table 3:
Table 3: 4 LED Voltage Thresholds
RBLVS (ohm)
LED1
50K
60K
70K
80K
3.35V
3.60V
3.75V
4.00V
3.45V
3.70V
3.85V
4.10V
3.55V
3.80V
3.95V
4.20V
3.65V
3.90V
4.05V
4.30V
Figure 5. Battery terminal voltage setting circuit
LED2
LED3
LED Status Indication
LED4
4 LEDs ON/OFF and flash show the charge status
and the remained capacity level as shown in the
table 2. The LED status is based on battery voltage
and operation modes. When battery voltage is low,
LED1 is flashing. In charge mode, when a battery is
fully charged, flashing stops and all the 4 LEDs are
solid on.
Input Current Limit
An external resistor is used to set the input current
limit connected from ILIM pin to AGND as shown in
Figure 7. Input current limit has built-in soft startup
and current foldback control loop. The input current
limit is estimated as the following equation:
Battery level voltage shift (BLVS pin)
LED1-4 voltage thresholds are adjusted from HZ
mode during charging and discharging based on
the compensated impedance. Those thresholds are
2.4 (V)
IILIM (A) =
(3)
RILIM (kΩ )
Table2: LED Indication
Charge Mode
PB time>100ms (Boost or HZ Mode)
LED
LED1
Flash
LED2
Off
LED3
Off
LED4
Off
LED1
Off
LED2
Off
LED3
Off
LED4
Off
VBAT<LED1(ACT2801-T0550)
VBAT<LED1
(ACT2801-T1026/ACT2801C)
Flash
Off
Off
Off
Flash
Off
Off
Off
LED1≤VBAT<LED2
LED2≤VBAT<LED3
LED3≤VBAT<LED4
VBAT≥LED4
On
On
On
On
Flash
On
Off
Flash
On
Off
Off
On
On
On
On
Off
On
On
On
Off
Off
On
On
Off
Off
Off
On
On
Flash
Flash
On
On
VBAT≥LED4
(End of Charge)
On
On
On
On
On
On
On
On
Innovative PowerTM
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