Analog Devices ADP3806 b Datasheet

High Frequency Switch Mode

Li-Ion Battery Charger

ADP3806

FEATURES
Li-Ion Battery Charger
Three Battery Voltage Options

Selectable 12.525 V/16.700 V
Selectable 12.600 V/16.800 V
Adjustable

High End-of-Charge Voltage Accuracy

ⴞ0.4% @ 25ⴗC
ⴞ0.6% @ 5ⴗC to 55ⴗC
ⴞ0.7% @ 0ⴗC to 85ⴗC

Programmable Charge Current with Rail-to-Rail

Sensing
System Current Sense with Reverse Input Protection
Soft-Start Charge Current
Undervoltage Lockout
Bootstrapped Synchronous Drive for External NMOS
Programmable Oscillator Frequency
Oscillator SYNC Pin
Low Current Flag
Trickle Charge

APPLICATIONS
Portable Computers
Fast Chargers

FUNCTIONAL BLOCK DIAGRAM

GENERAL DESCRIPTION

The ADP3806 is a complete Li-Ion battery-charging IC. The
device combines high output voltage accuracy with constant
current control to simplify the implementation of constant­current, constant-voltage (CCCV) chargers. The ADP3806 is
available in three options: The ADP3806-12.6 guarantees the
final battery voltage selected is 12.6 V or 16.8 V ± 0.6%, the
ADP3806-12.5 guarantees 12.525 V/16.7 V ± 0.6%, and the
ADP3806 is adjustable using two external resistors to set the
battery voltage. The current sense amplifier has rail-to-rail inputs
to accurately operate under low dropout and short-circuit condi­tions. The charge current is programmable with a dc voltage on
ISET. A second differential amplifier senses the system current
across an external sense resistor and outputs a linear voltage
on the ISYS pin. The bootstrapped synchronous driver allows
the use of two NMOS transistors for lower system cost.

BSTREG

SD

LC

VCC BST

VREF + VREG

UVLO

BIAS

LOGIC

CONTROL

DRVH DRVL

SW

BOOTSTRAPPED

SYNCHRONOUS

DRIVER

SD IN DRVLSD

VREF

PGND

DRVLSD

+

+

–

–

OSCILLATOR

ADP3806

AGND

REG

SYNC

CT

REV. B

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CS+

CS–

+–

AMP1

–

+

+

V

–

TH

–

gm1

+

–

gm2

+

VREF

COMPREF

One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] www.analog.com
Fax: [phone] © 2004 Analog Devices, Inc. All rights reserved.

SYS+ SYS– ISYS

+–

AMP2

2.5V

SELECT

12.6/16.8

BATSEL

–

+

LIMIT

ISET

BAT

ADP3806–SPECIFICATIONS

Parameter Conditions Symbol Min Typ Max Unit

BATTERY SENSE INPUT

ADP3806-12.6 V and 16.8 V
ADP3806-12.525 V and 16.7 V

= 25∞C, 13 V £ VCC £ 20 V V

T

A

5∞C £ T
0∞C £ T

Input Resistance Part in Operation R
Input Current Part in Shutdown I

BATTERY SENSE INPUT

ADP3806

= 2.5 V TA = 25∞C, 13 V £ VCC £ 20 V V

V

BAT

0∞C £ T
Input Current Operating BATSEL = Open, Part in Operation 0.2 1.0 mA
Input Current Shutdown BATSEL = 100 kW to GND, Part in Shutdown 0.2 1.0 mA

OSCILLATOR

Maximum Frequency
Frequency Variation

2

3

CT = 180 pF f
CT Charge Current I
0% Duty Cycle Threshold @ COMP Pin 1.0 V
Maximum Duty Cycle Threshold @ COMP Pin 2.5 V
SYNC Input High SYNC
SYNC Input Low SYNC
SYNC Input Current I

GATE DRIVE

On Resistance IL = 10 mA R
Rise, Fall Time C
Overlap Protection Delay DRVL Falling to DRVH Rising, t

DRVH Falling to DRVL Rising
SW Bias Current Part in Shutdown, V
BST Cap Refresh Threshold V

CURRENT SENSE AMPLIFIER

Input Common-Mode Range V
Input Differential Mode Range V
Input Offset Voltage

5

Gain

5

0 V £ V

Input Bias Current 0 V £ V
Input Offset Current 0 V £ V
Input Bias Current Part in Shutdown 0.2 1.0 mA
DRVL Shutdown Threshold Measured between V

SYSTEM CURRENT SENSE

6

Input Common-Mode Range SYS+ and SYS–, IL = 0 mA, V
Input Differential Range (V
Input Offset Voltage 0.5 mV
Input Bias Current, SYS+ V
Input Bias Current, SYS– V
Voltage Gain 10 V £ V
Output Range I
Limit Output Threshold V
Limit Output Voltage V

ISET INPUT

Charge Current Programming

Function 0.0 V < V

Programming Function Accuracy V

V

5∞C £ T

V
ISET Bias Current 0.0 V £ V

£ 55∞CV

A

£ 85∞CV

A

£ 85∞CV

A

= 1 nF, DRVL and DRVH tr, t

L

– V

BST

SW

and V

CS+

CS

SYS+

SYS(DM)

SYS(DM)

= 1 mA7, V

L

LIMIT

ISYS

ISET

ISET

CS(CM)

CS–

4

£ VCC V

CS(CM)

£ VCC, Part in Operation V

CS(CM)

£ VCC V

CS(CM)

) – (V

SYS–

= 0 V, V
= 0 V, V

SYS(CM)

SYS(CM)

£ 0.2 V, 50 kW Pull-up to 5 V V

> 2.65 V, I

£ 4.0 V V

ISET

= 4.0 V, 1 V £ V
= 0.50 V, 1 V £ V

£ 55∞C, V

A

= 5 V and 10 V

£ 4.0 V I

ISET

(@ 0ⴗC £ TA £ 100ⴗC, VCC = 16 V, unless otherwise noted.)

BAT

BAT

BAT

BAT

BAT(SD)

BAT

BAT

f

CT

CT

CT

H

L

SYNC

ON

f

OP

= 12.6 V 0.2 1.0 mA

SW

V

CS(CM)

V

CS(DM)

CS(VOS)

CS(IB)

CS(IOS)

and V

CS+

CS–

= 3 V V

ISYS

)V

= 16 V I

SYS(CM)

= 16 V I

SYS(CM)

V

)48 mV

CS(SD

SYS(CM)

SYS(DM)

B(SYS+)

B(SYS–)

£ VCC + 0.3 V, IL = 100 mA 48.5 50 51.5 V/V

> 6 V V

= 700 mAV

SINK

£ 16 V –5 ± 1.0 +5 %

CS(CM)

£ 10 V –30 ± 10 +30 %

CS(CM)

= 206 mV, –46.7 +33 %

ISET

ISYS

TH(LIMIT)

O(LIMIT)

ISET/VCS

B

–0.4 +0.4 %
–0.6 +0.6 %
–0.7 +0.7 %
250 350 kW

0.2 1.0 mA

–0.5 +0.5 %
–0.7 +0.7 %

1000 kHz
210 250 290 kHz
125 150 175 mA

2.2 V

0.8 V

0.2 1.0 mA

610 W
35 ns
50 ns

3.7 V

0.0 VCC + 0.3 V

0.0 160 mV

1.0 mV
25 V/V
50 100 mA

1.0 2.0 mA

4.0 VCC + 0.3 V
0 100 mV

200 300 mA
70 125 mA

0 5.0 V

2.3 2.5 2.7 V

0.1 0.2 V

25 V/V

0.2 1.0 mA

1

REV. B–2–

ADP3806

Parameter Conditions Symbol Min Typ Max Unit

BATSEL INPUT

V

= 12.6 V 2.0 V

BAT

= 16.8 V 0.8 V

V

BAT

BATSEL Input Current 0.2 5.0 mA

BOOST REGULATOR OUTPUT

Output Voltage CL = 0.1 mFV
Output Current

8

BSTREG

I

BSTREG

ANALOG REGULATOR OUTPUT

Output Voltage C
Output Current

8

= 10 nF V

L

I

REG

REG

PRECISION REFERENCE OUTPUT

Output Voltage V
Output Current

8

I

REF

REF

SHUTDOWN (SD)

ON SD
OFF SD

H

L

SD Input Current 0.2 1.0 mA

POWER SUPPLY

ON Supply Current No External Loads, UVLO £ VCC £ 20 V I
OFF Supply Current No External Loads, VCC £ 20 V I
UVLO Threshold Voltage Turn On V

SYON

SYOFF

UVLO

UVLO Hysteresis Turn Off 0.1 0.3 0.5 V

LC OUTPUT

Output Voltage Low High Current Mode9, I
Output Voltage High Low Current Mode

= 100 mA 0.1 0.4 V

SINK

10

OUTPUT REVERSE LEAKAGE

PROTECTION

Leakage Current VCC = Floating, V

= 12.6 V I

BAT

DISCH

OVERCURRENT COMPARATOR

Overcurrent Threshold V
Response Time VCS > 180 mV to COMP < 1 V t

CS(OC)

OC

OVERVOLTAGE COMPARATOR

Overvoltage Threshold V
Response Time V

NOTES

1

All limits at temperature extremes are guaranteed via correlation using standard Statistical Quality Control (SQC) methods.

2

Guaranteed by design, not tested in production.

3

If SYNC function is used, then f

4

VCS = (V

5

Accuracy guaranteed by ISET input, programming function accuracy specification.

6

System current sense is active during shutdown.

7

Load current is supplied through SYS+ pin.

8

Guaranteed output current from 0 to min specified value to maintain regulation.

9

V

BAT

10

V

) – (V

CS–

).

CS+

< 93% of final or VCS > 25 mV.

≥ 93% of final and VCS £ 25 mV.

BAT

Specifications subject to change without notice.

must be greater than fCT but less than 120% of fCT.

SYNC

> 120% to COMP < 1 V t

BAT

BAT(OV)

OV

6.8 7.0 7.2 V

3.0 5.0 mA

5.8 6.0 6.2 V

3.0 5.0 mA

2.47 2.5 2.53 V

0.5 1.1 mA

2.0 V

0.8 V

6.0 8.0 mA

1.0 5.0 mA

5.65 6.0 6.25 V

External V

15 mA

180 mV
2 ms

120 %
2 ms

REV. B

–3–

ADP3806

ABSOLUTE MAXIMUM RATINGS*

Input Voltage (VCC) . . . . . . . . . . . . . . . . . . . –0.3 V to +25 V

BAT, CS+, CS– . . . . . . . . . . . . . . . . . –0.3 V to VCC + 0.3 V

SYS+, SYS– . . . . . . . . . . . . . . . . . . . . . . . . . . –25 V to +25 V

BST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +30 V

BST to SW . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +8 V

SW to PGND . . . . . . . . . . . . . . . . . . . . . . . . . . –4 V to +25 V

DRVL to PGND . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +8 V

ISET, BATSEL, SD, SYNC, CT,

LIMIT, ISYS, LC . . . . . . . . . . . . . . . . . . . –0.3 V to +10 V

COMP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +3 V

GND to PGND . . . . . . . . . . . . . . . . . . . . . . . –0.3 V to +0.3 V

ORDERING GUIDE

Battery Package Package Quantity

Model Voltage Description Option per Reel

ADP3806JRU-REEL Adjustable TSSOP-24 RU-24 2500
ADP3806JRU-REEL7 Adjustable TSSOP-24 RU-24 1000
ADP3806JRU-12.5-RL 12.525 V/16.7 V TSSOP-24 RU-24 2500
ADP3806JRUZ-12.5RL

*

12.525 V/16.7 V TSSOP-24 RU-24 2500
ADP3806JRU-12.5-R7 12.525 V/16.7 V TSSOP-24 RU-24 1000
ADP3806JRU-12.6-RL 12.600 V/16.8 V TSSOP-24 RU-24 2500
ADP3806JRU-12.6-R7 12.600 V/16.8 V TSSOP-24 RU-24 1000

Operating Ambient Temperature Range . . . . . . 0∞C to 100∞C

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115∞C/W

␪

JA

Operating Junction Temperature Range . . . . . . 0∞C to 125∞C

Storage Temperature Range . . . . . . . . . . . . –65∞C to +150∞C

Lead Temperature Range (Soldering 10 sec) . . . . . . . . . 300∞C

*Stresses above those listed under Absolute Maximum Ratings may cause perma-

nent damage to the device. This is a stress rating only; functional operation of the
device at these or any other conditions above those listed in the operational
sections of this specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect device reliability. Absolute maximum
ratings apply individually only, not in combination. Unless otherwise specified all
other voltages are referenced to GND.

*Z = Pb-free part.

CAUTION

ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily
accumulate on the human body and test equipment and can discharge without detection. Although the
ADP3806 features proprietary ESD protection circuitry, permanent damage may occur on devices
subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended
to avoid performance degradation or loss of functionality.

REV. B–4–

ADP3806

PIN CONFIGURATION

VCC

SYS–

SYS+

ISYS

LIMIT

SYNC

REG

REF

COMP

CT

SD

LC

1

2

3

4

5

ADP3806

6

TOP VIEW

(Not to Scale)

7

8

9

10

11

12

24

23

22

21

20

19

18

17

16

15

14

13

SW

DRVH

BST

BSTREG

DRVL

PGND

CS+

CS–

ISET

BATSEL

BAT

AGND

PIN FUNCTION DESCRIPTION

Pin No. Mnemonic Function

1 VCC Supply Voltage.

2 SYS– Negative System Current Sense Input.

3 SYS+ Positive System Current Sense Input.

4 ISYS System Current Sense Output.

5 LIMIT System Current Sense Limit Output.

6CTOscillator Timing Capacitor.

7 SYNC Oscillator Synchronization Pin.

8 REG 6.0 V Analog Regulator Output.

PIN FUNCTION DESCRIPTION(continued)

Pin No. Mnemonic Function

9 REF 2.5 V Precision Reference Output.
10 SD Shutdown Control Input.

11 COMP External Compensation Node.

12 LC Low Current Output.

13 AGND Analog Ground.

14 BAT Battery Sense Input.

2.5 V for ADP3806.

12.525 V/16.7 V for ADP3806-12.5.

12.6 V/16.8 V for ADP3806-12.6.

15 BATSEL Battery Voltage Sense Input.

High = 3 Cells, Low = 4 Cells.

16 ISET Charge Current Program Input.

17 CS– Negative Current Sense Input.

18 CS+ Positive Current Sense Input.

19 PGND Power Ground.

20 DRVL Low Drive Output Switches between

REG and PGND.

21 BSTREG 7.0 V Regulator Output for Boost.

22 BST Floating Bootstrap Supply for DRVH.

23 DRVH High Drive Output Switches between

SW and BST.

24 SW Buck Switching Node Reference for

DRVH.

REV. B

–5–