1.

General Description

The FS3871 Lithium-Ion (Li-Ion) and Lithium-Polymer

(Li-Pol) linear charge-management ICs are designed for

cost sensitive and compact portable electronics. They

combine high-accuracy current and voltage regulation,

battery conditioning, temperature monitoring, charge

termination, charge-status indication, and Automatic

charge-rate compensation in a single 8-pin IC. TSSOP

package is offered to fit a wide range of end applications.

The FS3871 continuously measures battery temperature

using an external thermistor. For safety, the FS3871

inhibits charge until the battery temperature is within

user-defined thresholds. The FS3871 then charges the

battery in three phases: conditioning, constant current and

constant voltage. If the battery voltage is below the

low-voltage threshold, V(min), the FS3871 pre-charges

using a low current to condition the battery. The

conditioning charge rate is approximately 10% of the

regulation current. The conditioning current also minimizes

heat dissipation in the external pass element during the

initial stage of the charge. After conditioning, the FS3871

applies a constant current to the battery. An external

sense-resistor sets the current. The sense-resistor can be

on either the high or low side of the battery without

additional components. The constant-current phase

continues until the battery reaches the charge-regulation

voltage.

The available 8-pin TSSOP-8/MSOP-8 package is offered

for balanced area and cost effective requirements for

size-sensitive applications.

The FS3871 is suitable for the control of charge sequences

of a variety of portable battery-powered applications, such

as cellular phone’s travel and base charger devices, digital

camera, digital-video camcorder (DV), MP3 player ,etc.

2.

Features

Ideal for Single (4.1 V or 4.2 V) and Dual-Cell (8.2 V or 8.4

V) Li-Ion or Li-Poly Packs. (Dual-Cell is not available now)

0.3 V dropout voltage for minimizing heat dissipation.

Better than

1% voltage regulation accuracy with preset

voltages.

Automatic Dynamic Compensation of battery pack’s

internal impedance to reduce charge time.

Optional cell-temperature monitoring before and during

charge.

Integrated

voltage

and

current

regulation

with

programmable charge-current and high or low-side current

sensing.

Integrated cell conditioning for reviving deeply discharged

cells and minimizing heat dissipation during initial stage of

charge.

Charge status output for single or dual LED or host

processor interface.

Automatic battery-recharge feature.

Charge termination by minimum current.

Automatic low-power sleep mode when VCC is removed.

Low-cost peripheral components of capacitor and resistor

combinations for minimum BOM cost in manufacturing

considerations.

Evaluation (EV) board is available for quick evaluation.

TSSOP-8/MSOP-8 Green Package.

3.

Applications

Cellular phone external base or built-in charger

MP3/MP4 player

External charger through USB

Digital still camera (DSC)

Digital video camcorder (DV)

Portable electronic device charger, etc.