Product Introduction

Product parameters

Funtion：PFM Step-up 2-cell Lithium Battery Charger IC

Opration Mode：Switch

Battery：Lithium-ion

Battery No.：2

Vout Range：0V-8.4V

Vin Range：≥4.5V

Operating Current：380uA@VIN=5V

Solar Panel charge：No

Chip Temperature Regulation：Yes

Package：eSOP8

Chip Enable：No

On-chip Power MOSFET：No

General Descriptions:

CN3322 is a PFM mode step-up 2-cell Li-ion battery charging controller IC with minimum operating voltage down to 4.5V. CN3322 adopts trickle, constant current (CC) and quasi-constant voltage(Quasi-CV^TM) mode to charge battery.

On power up, CN3322 enters charging mode, the external N-channel MOSFET is turned on first, inductor current rises. When inductor current reaches upper limit, the N-channel MOSFET is turned off, the energy stored in inductor is transferred to battery. When the inductor current is discharged to its lower limit, the N-channel MOSFET is turned on again, and so forth. When BAT pin voltage reaches 8.4V(Typ.) for the first time, CN3322 enters quasi-CV mode, in which the charge current is reduced. The charge process will not be terminated until BAT voltage reaches 8.4V for the second time. In termination mode, the N-channel MOSFET is turned off. If BAT pin voltage falls below recharge threshold, CN3322 enters charge mode again. CN3322’s switching frequency can be up to 1MHz, which makes a small-profile inductor usable.

The other features include self-adaptive function to input supply, JEITA-compliant battery temperature monitoring, chip over temperature protection and status indication, etc.

CN3322 is available in thermally-enhanced 8-pin SOP package.

Applications:

l Standalone 2-cell Battery Charger

l Electrical Appliance

l Audio Systems

l POS, etc.

Features:

l Minimum Operating Voltage: 4.5V

l Fixed Charge Termination Voltage: 8.4V

l Self-adaptive to Input Supply

l Operating Current: 380uA@VIN=5V

l Inductor Current Sensing