Overview: CN3125 is a charging chip with constant current/constant voltage function. The input voltage range is 2.7V to 6V, and it can manage the charging of single-cell or double-cell supercapacitors. CN3125 has an internal power transistor and does not require external blocking diodes or current detection resistors. CN3125 requires very few external components, making it ideal for portable applications. A thermal modulation circuit can control the chip temperature within a safe range when the device's power consumption is high or the ambient temperature is high. The constant voltage charging voltage is set by the voltage divider resistor on the FB pin, and the constant current charging current is set by the resistor on the ISET pin. CN3125 has an internal capacitor voltage automatic balancing circuit to prevent capacitor overvoltage during charging. When the input voltage is cut off, CN3125 automatically enters a low-power sleep mode, at which time the current consumption of the TOP pin and MID pin is less than 3 microamps. Other functions include a chip enable input, power undervoltage detection, and supercapacitor ready status output. CN3125 uses a heat-enhanced 8-pin small outline package (eSOP8).

Product Parameters

Main Functions: Linear supercapacitor charging integrated circuit with balancing function

Operating Mode: Linear

Battery Type: Supercapacitor

Number of Batteries: 1-2

Input Voltage: 2.7V-6V

Output Voltage Range: 0V-5.8V

Maximum Charging Current: 1A

Maximum Output Current: 1A

Operating Current: 470uA

Solar Power Supply: No

Thermal Modulation: Yes

Packaging Form: eSOP8

Chip Enable: Yes

Built-in Power Tube: Yes

Applications ：

l Electric meter

l Supercapacitor backup power supply applications

l PC card, USB modem

l Portable instruments

Features ：

l Input voltage range: 2.7V to 6V

l Internal power transistor

l No external current limiting diodes and current detection resistors required

l Constant voltage charging voltage is set by external voltage divider resistors

l Constant current charging current is set by ISET pin resistor

l Continuous charging current up to 1.5A

l Capacitor voltage automatic balancing function to prevent capacitor overvoltage

l Charging using constant current/constant voltage/constant temperature mode, maximizing charging current while preventing chip overheating

l Automatically enters low-power sleep mode when power supply voltage drops

l Supercapacitor voltage ready status output terminal

l Chip enable input terminal

l Uses eSOP8 package

l Lead-free product, RoHS compliant, halogen-free