1

LTC1729 Series

s

Built-In Termination: 3-Hour Time-Out

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C/10 Detection with Status Indicator

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Trickle Charge Preconditioning If Cell < 2.7V

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Charging Enabled When 0

°C < T < 50°C

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Automatic Charger Present Detection

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Automatic Battery Present Detection

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1- or 2-Cell, 4.1V/Cell or 4.2V/Cell Options

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Precision Internal 0.2% Voltage Feedback Divider

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Compatible with LT1505/LT1510/LT1511/

LT1512/LT1513/LT1769

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Small Footprint/Low Profile

The LTC

controllers for lithium-ion battery chargers. These ICs

provide trickle charge preconditioning, temperature charge

qualification, time or charge current termination, auto-

matic charger and battery detection and status output.

Combining the LTC1729 series part with the LT

(1.5A), LT1769 (2A), LT1511 (3A) and LT1505 (> 4A)

step-down chargers is a simple operation. Connecting six

pins from the LTC1729 series part to the step-down

chargers completes the integration. The LTC1729 termi-

nation controllers are also compatible with step-down/

step-up (SEPIC) chargers, including the LT1512 (2A switch)

and LT1513 (3A switch).

The LTC1729 series is available in the 8-pin MSOP and SO

packages.

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Cellular Phones

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PDAs

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Cradle Chargers

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Camcorders

Figure 1. 500kHz Li-Ion Cell Phone Charger (0.8A)

Li-Ion Battery Charger

Termination Controllers

, LTC and LT are registered trademarks of Linear Technology Corporation.

OVP

BAT

SENSE

GND

STATUS

NTC

SW

SENSE

OVP

GND

BOOST

PROG

BAT

1

2

3

4

8

7

6

5

LTC1729-4.2

LT1510-5

1

µF

0.22

µF

L1**

10

µH

0.1

µF

1729 F01

OPTION: TIE RESISTOR TO STATUS FOR

CHARGE TERMINATION AT

LOW CHARGING CURRENT

* TOKIN OR MARCON SURFACE MOUNT

** COILTRONICS TP3-100, 10

µH, 2.2mm HEIGHT

(0.8A CHARGING CURRENT)

COILTRONICS TP1 SERIES, 10

µH, 1.8mm

HEIGHT (<0.5A CHARGING CURRENT)

*** PANASONIC EEFCD1B220

10k NTC THERMISTOR, NTHS1206N02 VISHAY/DALE

NOTE: EITHER A THERMISTOR OR 10k RESISTOR MUST BE PRESENT

0.1

µF

1

µF

1k

22

µF

4.2V

200

Ω

300

Ω

6.19k

+

10

µF

MBRM120T3

INPUT POWER

8.2V TO 20V

CHARGE STATUS

MBRM120T3

MMBD914L

1.4k

+

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO