LP28013A-01

Oct.-2018

www.lowpowersemi.com

Page 5 of 7

Preliminary Datasheet

LP28013A

Application Information

Input Voltage Range

The LP28013A has built-in input voltage surge protection as

high as +28V. The charger IC will be automatically disabled

when the input voltage is lower than 3.3V or higher than 7.0V.

The open-drain PG Pin is used to indicate an input power

good condition (3.3V<VIN<7.0V). If the input voltage is lower

than the battery voltage, the IC is also disabled to prevent the

battery from draining.

A charge cycle begins when the voltage at the VIN pin rises

above the UVLO threshold level, when a battery is connected

to the charger output. If the BAT pin is less than 2.6V, the

charger enters trickle charge mode. In this mode, the

LP28013A

supplies

approximately

1/10

the

ISET

programmed charge current to bring the battery voltage up to

a safe level for full current charging. When the BAT pin

voltage rises above 2.6V, the charger enters constant-current

mode(CC), where the ISET programmed charge current is

supplied to the battery. When the BAT pin approaches the

final float voltage, the LP28013A enters constant-voltage

mode(CV) and the charge current begins to decrease, and the

battery full indicator is set when the charge current in CV

mode is reduced to 1/10 of the CC mode.

ISET programming Charge Current

connecting from the ISET pin to GND. The relationship of the

charge current and the programming resistance is established

by the following formula:

Termination charge current programmed

Battery Temperature Detection

The NTC function for the LP28013A is designed to follow the

new JEITA temperature standard for Li-Ion. There are now

three thresholds, 60°C, 10°C, and 0°C. Normal operation

occurs between 10°C and 60°C. If between 0°C and 10°C the

charge current level is cut in half. Above 60°C or below 0°C

the charge is disabled.

The NTC feature is implemented using an internal 48μA

current source to bias the thermistor connected from the NTC

terminal to GND (designed for use with a 10k NTC β = 3370

[SEMITEC 103AT-2 or Mitsubishi TH05-3H103F]). If NTC

feature is not needed, a fixed 10kΩ can be placed between

current is fixed along with the temperature thresholds, it is not

possible to use thermistor values other than the 10k NTC (at

25°C).