1

2

3

4

8

7

6

5

SNS

LED

BAT

VSS

MOD

VCC

TS

RC

bq24400

www.ti.com

SLUS498A – SEPTEMBER 2001 – REVISED FEBRUARY 2010

Programmable NiCd/NiMH Fast-Charge Management IC

Check for Samples: bq24400

1

FEATURES

GENERAL DESCRIPTION

•

Safe Management of Fast Charge for NiCd and

NiMH Battery Packs

The bq24400 is a programmable, monolithic IC for

fast-charge management of nickel cadmium (NiCd)

•

High-Frequency Switching Controller for

and nickel metal-hydride (NiMH) in single or multi-cell

Efficient and Simple Charger Design

applications.

•

Pre-Charge Qualification for Detecting

The bq24400 provides these charge termination

Shorted, Damaged, or Overheated Cells

criteria:

•

Fast-Charge Termination by Peak Voltage

•

Peak voltage, PVD

(PVD), Maximum Temperature, and Maximum

•

Maximum temperature

Charge Time

•

Maximum charge time

•

Selectable Top-Off Mode for Achieving

Maximum Capacity in NiMH Batteries

For safety, the bq24400 inhibits fast charge until the

battery

voltage

and

temperature

are

within

•

Programmable Trickle-Charge Mode for

user-defined limits. If the battery voltage is below the

Reviving Deeply Discharged Batteries and for

low-voltage

threshold,

the

bq24400

uses

Postcharge Maintenance

trickle-charge to condition the battery. For NiMH

•

Built-in Battery Removal and Insertion

batteries, the bq24400 provides an optional top-off

Detection

charge to maximize the battery capacity.

•

Sleep Mode for Low Power Consumption

The integrated high-speed comparator allows the

bq24400

to

be

the

basis

for

a

complete,

APPLICATIONS

high-efficiency battery charger circuit for nickel-based

•

Nickel Charger

chemistries.

•

High-Power, Multi-Cell Charger

spacer between para and illustration

8-Pin DIP or Narrow SOIC or TSSOP

Pin Names

SNS

Current-sense input

System ground

LED

Charge-status output

BAT

Battery-voltage input

TS

Temperature-sense input

RC

Timer-program input

Supply-voltage input

MOD

Modulation-control output

1

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas

Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date.

Copyright © 2001–2010, Texas Instruments Incorporated

Products conform to specifications per the terms of the Texas

Instruments standard warranty. Production processing does not

necessarily include testing of all parameters.