ACE4702

2 Cell Li-ion Battery Charger IC

VER 1.1

12

Diode Selection

The diodes D1 and D2 in Figure 1 are schottky diode, the current rating of the diodes should be at least

the charge current limit, the voltage rating of the diode should exceed the maximum expected input

voltage. The diode that is much larger than that is sufficient can result in larger transition losses due to

their larger junction capacitance.

Disable Charging with TEMP Pin

The charging can be disable with TEMP pin, as shown in Figure3:

Figure3 Disable Charging Whth TEMP Pin

When control signal is high, N-channel MOSFET M1 is turned on, the voltage at TEMP pin is pulled

down to GND, which will disable the charging;

When control signal is low, N-channel MOSFET is turned off, the voltage at TEMP pin is determined by

NTC thermistor, which performs normal battery temperature monitoring function.

About Battery Current in Sleep Mode

In the typical application circuit shown in Figure 1, when input voltage is powered off or lower than

battery voltage, ACE4702 will enter sleep mode. In sleep mode, the battery current includes:

erratic operation, a resistor in parallel with capacitance C1 may be needed to discharge the

capacitance, the

resistor value is determined by diode D1’s leakage, generally speaking, a 20KΩ

resistor can achieve the task.

The current from battery to GND via diode D2, which is also determined by D2’s leakage current.

ACE4702