Linear Technology LTC4002ES8-4.2, LTC4002EDD-4.2 Datasheet

LTC4002-4.2

Final Electrical Specifications

Standalone Li-Ion

Switch Mode Battery Charger

FEATURES

■

Wide Input Supply Range: 4.7V to 24V

■

High Efficiency Current Mode PWM Controller with
500kHz Switching Frequency

■

±1% Charge Voltage Accuracy

■

End-of-Charge Current Detection Output

■

3 Hour Charge Termination Timer

■

Constant Switching Frequency for Minimum Noise

■

±5% Charge Current Accuracy

■

Low 10µA Reverse Battery Drain Current

■

Automatic Battery Recharge

■

Automatic Shutdown When Input Supply is Removed

■

Automatic Trickle Charging of Low Voltage Batteries

■

Battery Temperature Sensing and Charge
Qualification

■

Stable with Ceramic Output Capacitor

■

8-Lead SO and 10-Lead DFN Packages

U

APPLICATIO S

■

Portable Computers

■

Charging Docks

■

Handheld Instruments

U

June 2003

DESCRIPTIO

The LTC®4002-4.2 is a complete battery charger controller
for single cell 4.2V lithium-ion batteries. With a 500kHz
switching frequency, the LTC4002-4.2 provides a small,
simple and efficient solution to fast charge Li-Ion batteries
from a wide range of supply voltages. An external sense
resistor sets the charge current with ±5% accuracy. An
internal resistor divider and precision reference set the
final float voltage to 4.2V with ±1% accuracy.

When the input supply is removed, the LTC4002-4.2
automatically enters a low current sleep mode, dropping
the battery drain current to 10µA. An internal comparator
detects the near end-of-charge condition while an internal
timer sets the total charge time and terminates the charge
cycle. After the charge cycle ends, if the battery voltage
drops below 4.05V, a new charge cycle will automatically
begin.

The LTC4002-4.2 is available in the 8-lead SO and 10-lead
DFN packages.

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

TYPICAL APPLICATIO

BAT

2k

CHARGE

STATUS

2.2k

Figure 1. 1.5A Single Cell Li-Ion Battery Charger

0.1µF
CER

0.47µF

U

V

IN

5V TO 24V

B330B-13

2

V

CC

LTC4002ES8-4.2

5

CHRG

COMP

NTC GND

10k

T

NTC

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen­tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

3

GATE

7

SENSE

61

BAT

48

NTC: DALE NTHS-1206N02

Si6435ADQ

L1

6.8µH

68mΩ

22µF
CER

+

10µF
CER

B330B-13

Li-Ion
BATTERY

400242 F01

100

I

CHRG

R

SENSE

(CURVES INCLUDE
INPUT DIODE)

90

80

EFFICIENCY (%)

70

60

5

Efficiency vs Input Voltage

= 1.5A

= 68mΩ

= 4V

V

BAT

V

= 3.8V

BAT

10

15

INPUT VOLTAGE (V)

20

400242 TA02

25

400242i

1

LTC4002-4.2

1

2

3

4

8

7

6

5

TOP VIEW

NTC
SENSE
BAT
CHRG

COMP

V

CC

GATE

GND

S8 PACKAGE

8-LEAD PLASTIC SO

TOP VIEW

11

DD PACKAGE

10-LEAD (3mm × 3mm) PLASTIC DFN

10

9

6

7

8
4
5

3

2

1

NC
NTC
SENSE
BAT
CHRG

COMP

V

CC

GATE
PGND
SGND

WW

W

ABSOLUTE AXI U RATI GS

U

(Note 1)

Supply Voltage (VCC) .............................................. 24V

GATE .................................................. (VCC –8V) to V

CC

BAT, SENSE .............................................. –0.3V to 14V

CHRG, COMP, NTC ..................................... – 0.3V to 8V

UUW

PACKAGE/ORDER I FOR ATIO

ORDER PART

NUMBER

LTC4002EDD-4.2

DD PART MARKING

T

= 125°C, θJA = 43°C/W

JMAX

EXPOSED PAD IS GND (PIN 11)

MUST BE SOLDERED TO PCB

Consult LTC Marketing for parts specified with wider operating temperature ranges.

LAGG

Operating Temperature Range (Note 2) .. – 40°C to 85°C

Storage Temperature Range ................. –65°C to 150°C

Lead Temperature (Soldering, 10 sec).................. 300°C

ORDER PART

NUMBER

LTC4002ES8-4.2

S8 PART MARKING

T

= 125°C, θJA = 110°C/W

JMAX

400242

ELECTRICAL CHARACTERISTICS

temperature range, otherwise specifications are at TA = 25°C. VCC = 10V unless otherwise noted.

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
DC Characteristics

V

CC

I

CC

V

BAT

V

SNS(CHG)

V

SNS(TRKL)

V

TRKL

V

UV

∆V

UV

V

MSD

V

ASD

I

COMP

I

CHRG

V

CHRG

R

EOC

t

TIMER

2

VCC Supply Voltage ● 4.7 24 V
VCC Supply Current Current Mode 3 5 mA

Battery Regulated Float Voltage 5V ≤ VCC ≤ 24V (Note 2) 4.168 4.2 4.232 V

Constant Current Sense Voltage 3V ≤ V

Trickle Current Sense Voltage V
Trickle Charge Threshold Voltage V
VCC Undervoltage Lockout Threshold Voltage VCC Rising 3.9 4.2 4.5 V
VCC Undervoltage Lockout Hysteresis Voltage 200 mV
Manual Shutdown Threshold Voltage COMP Pin Falling 200 360 500 mV
Automatic Shutdown Threshold Voltage VCC – V
COMP Pin Output Current V
CHRG Pin Weak Pull-Down Current V
CHRG Pin Output Low Voltage I
End-of-Charge Ratio V
Charge Time Accuracy 10 %

The ● denotes the specifications which apply over the full operating

Shutdown Mode 3 5 mA
Sleep Mode 10 20 µA

● 4.158 4.242 V

≤ 4V (Note 3) 0°C ≤ TA ≤ 85°C ● 93 100 107 mV

BAT

= 0V (Note 3) 5 10 15 mV

BAT

Rising 2.75 2.9 3.05 V

BAT

BAT

= 1.2V 100 µA

COMP

= 1V 15 25 35 µA

CHRG

= 1mA 0.15 0.3 V

CHRG

SNS(EOC)/VSNS(CHG)

–40°C ≤ T

≤ 85°C ● 90 110 mV

A

250 mV

10 25 32 %

400242i

LTC4002-4.2

TEMPERATURE (°C)

–50

f

OSC

(kHz)

25

400242 G03

500

–25 0 50

450

550

75 100 125

ELECTRICAL CHARACTERISTICS

The ● denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at TA = 25°C. VCC = 10V unless otherwise noted.

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

I

NTC

V

NTC-HOT

V

NTC-COLD

∆V

RECHRG

I

LEAK

Oscillator

f

OSC

DC Maximum Duty Cycle 100 %

Gate Drive

t

r

t

f

∆V

GATE

∆V

GATEHI

∆V

GATELO

Note 1: Absolute Maximum Rating are those values beyond which the life
of a device may be impaired.

NTC Pin Output Current V
NTC Pin Threshold Voltage (Hot) V

= 0.85V ● 75 85 95 µA

NTC

Falling ● 340 355 370 mV

NTC

Hysteresis 25 mV

NTC Pin Threshold Voltage (Cold) V

Rising ● 2.428 2.465 2.502 V

NTC

Hysteresis 170 mV

Recharge Battery Voltage Offset from Full V

BAT(FULLCHARGED)

– V

RECHRG

, V

Falling 100 150 200 mV

BAT

Charged Battery Voltage
CHRG Pin Leakage Current V

= 8V, Charging Stops 1 µA

CHRG

Switching Frequency 450 500 550 kHz

Rise Time C
Fall Time C
Output Clamp Voltage VCC – V
Output High Voltage ∆V
Output Low Voltage ∆V

= 2000pF, 10% to 90% 20 ns

GATE

= 2000pF, 90% to 10% 50 ns

GATE

, VCC ≥ 9V ● 8V

GATE

GATEHI

GATELO

= VCC – V

= VCC – V

, VCC ≥ 7V ● 0.3 V

GATE

, VCC ≥ 7V ● 4.5 V

GATE

Note 2: The LTC4002-4.2 is tested with Test Circuit 1.
Note 3: The LTC4002-4.2 is tested with Test Circuit 2.

UW

TYPICAL PERFOR A CE CHARACTERISTICS

Supply Current vs Temperature Supply Current vs V

4.0

3.5

(mA)

CC

I

3.0

2.5
–50

–25 0

50 100 125

25 75

TEMPERATURE (°C)

400242 G01

(mA)

CC

I

4

3

2

CURRENT MODE

5

10

15

VCC (V)

CC

20

TA = 25°C, VCC = 10V unless otherwise noted.

Oscillator Frequency
vs Temperature

25

400242 G02

400242i

3

LTC4002-4.2

VCC (V)

5

22

I

CHRG

(µA)

25

28

10 15 20 25

400242 G11

V

CHRG

= 8V

UW

TYPICAL PERFOR A CE CHARACTERISTICS

TA = 25°C, VCC = 10V unless otherwise noted.

Oscillator Frequency vs V

510

(kHz)

500

OSC

f

490

5

10

VCC (V)

Trickle Charge Voltage
vs Temperature

3.0

(V)

2.9

TRKL

V

Current Mode Sense Voltage

CC

15

20

25

400242 G04

vs Temperature

104

V

= 4V

BAT

(mV)

100

SNS

V

96

–25 0 50

–50

25

TEMPERATURE (°C)

75 100 125

400242 G05

Trickle Charge Voltage
vs V

CC

3.0
V

= 4V

BAT

(V)

2.9

TRKL

V

Current Mode Sense Voltage
vs V

CC

102

V

= 4V

BAT

(mV)

100

SNS

V

98

5

10

15

VCC (V)

CHRG Pin Output Low Voltage
vs V

CC

150

I

= 1mA

LOAD

(mV)

140

CHRG

V

20

25

400242 G04

2.8
–25 0 50

–50

25

TEMPERATURE (°C)

75 100 125

400242 G07

CHRG Pin Output Low Voltage
vs Temperature

180

I

= 1mA

LOAD

(mV)

140

CHG

V

100

–25 0 50

–50

4

25

TEMPERATURE (°C)

75 100 125

400242 G10

2.8
5

10

15

VCC (V)

CHRG Pin Weak Pull-Down
Current vs Temperature

29

V

= 8V

CHRG

(µA)

25

CHRG

I

21

–25 0 50

–50

25

TEMPERATURE (°C)

20

400242 G08

75 100 125

400242 G23

25

130

5

10

15

VCC (V)

20

25

400242 G09

CHRG Output Pin Weak Pull-Down
Current vs V

CC

400242i

TEMPERATURE (°C)

–50

I

NTC

(µA)

25

400242 G17

85

–25 0 50

81

89

75 100 125

V

NTC

= 0V

TEMPERATURE (°C)

–50

R

EOC

(%)

25

400242 G20

25

–25 0 50

21

29

75 100 125

UW

TYPICAL PERFOR A CE CHARACTERISTICS

LTC4002-4.2

TA = 25°C, VCC = 10V unless otherwise noted.

Trickle Charge Sense Voltage
vs Temperature

10.4
V

= 2.5V

BAT

(mV)

10.0

SNS

V

9.6
–25 0 50

–50

25

TEMPERATURE (°C)

COMP Pin Output Current
vs Temperature

104

V

= 0V

COMP

75 100 125

400242 G12

Trickle Charge Sense Voltage
vs V

CC

11

V

= 2.5V

BAT

(mV)

10

SNS

V

9

5

10

15

V

(V)

CC

NTC Pin Output Current
vs V

CC

86

V

= 0V

NTC

COMP Pin Output Current
vs V

CC

102

V

= 0V

COMP

(µA)

100

COMP

I

20

25

400242 G13

98

5

10

15

VCC (V)

20

25

400242 G14

NTC Pin Output Current
vs Temperature

(µA)

100

COMP

I

96

–25 0 50

–50

25

TEMPERATURE (°C)

75 100 125

400242 G15

Recharge Voltage Offset from Full
Charged Voltage vs Temperature

190

(mV)

150

RECHRG

∆V

110

–25 0 50

–50

25

TEMPERATURE (°C)

75 100 125

400242 G18

(µA)

85

NTC

I

84

5

10

15

VCC (V)

Recharge Voltage Offset from Full
Charged Voltage vs V

160

(mV)

150

RECHRG

∆V

140

5

10

CC

15

VCC (V)

20

25

400242 G16

End-of-Charge Ratio
vs Temperature

20

25

400242 G19

400242i

5