4

Pin Configurations

Package Type

Pin Configurations

SOP-8

Pin Description

PIN

SOP-8

DESCRIPTION

SENSE

1

Current Amplifier Sense Input. A sense resistor, RSENSE, must be connected between

the SENSE and BAT pins. The maximum charge current is equal to 100mV/RSENSE.

NTC

2

NTC (Negative Temperature Coefficient) Thermistor Input. With an external 10k NTC

thermistor to ground, this pin senses the temperature of the battery pack and stops the

charger when the temperature is out of range. To disable the temperature qualification

function, ground the NTC pin.

COMP

3

Compensation, Soft-Start and Shutdown Control Pin. Charging begins when the COMP

pin reaches 850mV. The recommended compensation components are a 2.2µF (or larger)

capacitor and a 0.5k series resistor (or small). A 100µA current into the compensation

capacitor also sets the soft-start slew rate. Pulling the COMP pin below 280mV will shut

down the charger.

VCC

4

Positive Supply Voltage Input.

SW

5

Power Switching Output.

GND

6

IC Ground.

CHRG

7

Charge Status Output.

BAT

8

Battery Sense Input. A bypass capacitor of 22µF is required to minimize ripple voltage.

HM4066-4.2 /8.4/ 8.34