LP3921

SNVS580A – AUGUST 2008 – REVISED MAY 2013

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Charger Electrical Characteristics (continued)

Unless otherwise noted, VCHG-IN = 5V, VIN (=VIN1=VIN2=BATT=VDD) = 3.6V.CCHG_IN = 10 µF. Charger set to default settings

unless otherwise noted. Typical values and limits appearing in normal type apply for TJ = 25°C. Limits appearing in boldface

type apply over the entire junction temperature range for operation, TA = TJ = −25°C to +85°C.

(1)(2)

Limit

Symbol

Parameter

Condition

Typ

Units

Min

Max

VTERM

Battery Charge Termination

Default

4.2

V

voltage

VTERM voltage tolerance

TJ = 0°C to 85°C

-1

+1

%

ICHG

Fast Charge Current Accuracy

ICHG = 450 mA

-10

+10

%

Programmable full-rate charge

6.0V

≥ VCHG_IN ≥ 4.5V

50

950

mA

current range (default 100 mA)

VBATT < (VCHG_IN - VOK_CHG)

VFULL_RATE < VBATT < VTERM

(4)

Default

100

Charge current programming

50

step

IPREQUAL

Pre-qualification current

VBATT = 2V

50

40

60

mA

ICHG_USB

CHG_IN programmable

5.5V

≥ VCHG_IN ≥

Low

current in USB mode

4.5V

100

VBATT < (VCHG_IN

- VOK_CHG)

mA

VFULL_RATE <

High

450

VBATT < VTERM

Default = 100 mA

100

VFULL_RATE

Full-rate qualification threshold VBATT rising, transition from pre-qual to full-rate

3

2.9

3.1

V

charging

IEOC

End of Charge Current, % of

0.1C option selected

10

%

full-rate current

VRESTART

Restart threshold voltage

VBATT falling, transition from EOC to full-rate

4.05

3.97

4.13

V

charge mode. Default options selected - 4.05V

IMON

IMON Voltage 1

ICHG = 100 mA

0.247

V

IMON Voltage 2

ICHG = 450 mA

1.112

0.947

1.277

TREG

Regulated junction

(5)

115

°C

temperature

Detection and Timing(5)

TPOK

Power OK deglitch time

VBATT < (VCC - VOK_CHG)

32

mS

TPQ_FULL

Deglitch time

Pre-qualification to full-rate charge transition

230

mS

TCHG

Charge timer

Precharge mode

1

Hrs

Charging Timeout

5

TEOC

Deglitch time for end-of-

230

mS

charge transition

(4)

Full-charge current is specified for CHG_IN = 4.5 to 6.0V. At higher input voltages, increased power dissipation may cause the thermal

regulation to limit the current to a safe level, resulting in longer charging time.

(5)

Specified by design.

12

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