CN3323 PFM Boost Three-cell Lithium Battery Charging Control IC - SOP-8

CN3323 PFM Boost Three-cell Lithium Battery Charging Control IC - SOP-8

CN3323 is a PFM boost type three-cell lithium battery charge management integrated circuit.  CN3323 uses trickle current, constant current and quasi-constant voltage mode (Quasi-CV TM ) to manage the charge of three lithium batteries. It integrates a reference voltage source, an inductor current detection unit, a control circuit and an off-chip field effect transistor drive circuit, etc. It has the advantages of few external components and simple circuit.

When the input power is turned on, CN3323 enters the charging state, controls the off-chip N- channel MOSFET to turn on, and the inductor current rises. When it rises to the upper limit set by the external current detection resistor, the off-chip N- channel MOSFET is turned off, the inductor current drops, and the energy in the inductor is transferred to the battery. When the inductor current drops to the lower limit set by the external current detection resistor, the off-chip N - channel MOSFET is turned on again, and the cycle continues. When the BAT pin voltage reaches 12.6V ( typical value ) for the first time , CN3323 enters the quasi-constant voltage charging mode and charges the battery with a small current. Only when the BAT pin voltage reaches 12.6V for the second time , the charging process ends, and the off-chip N- channel MOSFET remains in the off state. At the end of charging, when the BAT pin voltage drops to the recharge threshold, CN3323 enters the charging state again. The maximum operating frequency of CN3323 can reach 1MHz , and the operating temperature range is from -40 ℃ to + 85 ℃.

Other features include input power adaptation, battery temperature monitoring in compliance with JEITA standards, battery overvoltage protection, chip overtemperature protection, two open-drain status indication outputs, etc.