SM6780AS

NIPPON PRECISION CIRCUITS—1

NIPPON PRECISION CIRCUITS INC.

Ni-Cd/Ni-MH Battery Charger IC

OVERVIEW

The SM6780AS is a quick charge control IC for Nickel-Cadmium (Ni-Cd) and Nickel Metal Hydride (Ni-MH)

rechargeable batteries. It supports quick charge, supplemental and pulse trickle charging modes. The charging

mode is selected automatically in response to the battery voltage, temperature and charging time.

The quick charge uses either negative delta voltage detection (

−∆V), temperature detection (∆T/∆t), or charg-

ing time cutoff to control the charging process. In addition, the quick charge mode can be placed on hold, if the

battery voltage or battery temperature are abnormal, until normal conditions are restored.

The SM6780AS requires few external components to realize a high-stability quick charge battery charger.

FEATURES

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Ni-Cd/Ni-MH battery quick charge control

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−∆V, ∆T/∆t, and maximum charge time cutoffs

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3 charge modes (quick charge, supplemental,

pulse trickle charge)

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3 selectable charge times (80, 120, and 240 min-

utes)

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Charge condition LED indicator output (on,

pulsed, off)

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Low power dissipation mode

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4.0 to 5.5V operating supply voltage

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300sec (typ)

−∆V detection invalid time

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8mV (typ)

−∆V detection accuracy

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25mV/min (typ)

∆T/∆t detection accuracy

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8-pin SOP package

ORDERING INFORMATION

PINOUT

(Top view)

PACKAGE DIMENSIONS

(Unit: mm)

Device

Package

SM6780AS

8-pin SOP

TIME

CHGN

INH

VDD

TEMP

LEDN

BATT

VSS

5.2 0.3

0.4 0.1

− 0.05

0 to 10

0.695typ

1.27

0.10