Intersil ISL 88731A Datasheet

®

ISL88731A

Data Sheet January 7, 2009

SMBus Level 2 Battery Charger

The ISL88731A is a highly integrated Lithium-ion battery
charger controller, programmab le over the SMBus system
management bus (SMBus). The ISL88731A is intended to be
used in a smart battery charger (SBC) within a smart battery
system (SBS) that throttles the charge power such that the
current from the AC-adapter is automatically limited. High
efficiency is achieved with a DC/DC synchronous-rectifier
buck converter, equipped with diode emulati on for enhanced
light load efficiency and system bus boosting prevention. The
ISL88731A charges one to four Lithium-ion series cells, and
delivers up to 8A charge current. Integrated MOSFET
drivers and bootstrap diode result in fewer components and
smaller implementation area. Low offset current-sense
amplifiers provide high accuracy with 10mΩ sense resistors.
The ISL88731A provides 0.5% end-of-charge battery
voltage accuracy.

The ISL88731A provides a digital output that indicates the
presence of the AC-adapter as well as an analog output
which indicates the adapter current within 4% accuracy.

The ISL88731A is available in a small 5mmx5mm 28 Ld thin
(0.8mm) QFN package. An evaluation kit is available to
reduce design time. The ISL88731A is available in Pb-Free
packages.

Pinout

ISL88731A

(28 LD TQFN)

TOP VIEW

CSSP

CSSN

VCC

BOOT

UGATE

PHASE

DCIN

28 27 26 25 24 23 22

NC

ACIN

VREF

ICOMP

NC

VCOMP

NC

1

2

3

4

5

6

7

8 9 10 11 12 13 14

ICM

SDA

SCL

VDDSMB

GND

ACOK

NC

21

20

19

18

17

16

15

VDDP

LGATE

PGND

CSOP

CSON

NC

VFB

FN6738.1

Features

• 0.5% Battery Voltage Accuracy

• 3% Adapter Current Limit Accuracy

• 3% Charge Current Accuracy

• SMBus 2 Wire Serial Interface

• Battery Short Circuit Protection

• Fast Response for Pulse-Charging

• Fast System-Load Transient Response

• Monitor Outputs

- Adapter Current (3% Accuracy)

- AC-Adapter Detection

• 11-Bit Battery Voltage Setting

• 6 Bit Charge Current/Adapter Current Setting

• 8A Maximum Battery Charger Current

• 11A Maximum Adapter Current

• +8V to +28V Adapter Voltage Range

• Pb-Free (RoHS compliant)

Applications

• Notebook Computers

• Tablet PCs

• Portable Equipment with Rechargeable Batteries

Ordering Information

PART

NUMBER

(Note)

ISL88731AHRZ ISL887

ISL88731AHRZ-T* ISL887

*Please refer to TB347 for details on reel specifications.
NOTE: These Intersil Pb-free plastic packaged products employ special
Pb-free material sets, molding compounds/die attach materials, and
100% matte tin plate plus anneal (e3 termination finish, which is RoHS
compliant and compatible with both SnPb and Pb-free soldering
operations). Intersil Pb-free products are MSL classified at Pb-free peak
reflow temperatures that meet or exceed the Pb-free requirements of
IPC/JEDEC J STD-020.

PART

MARKING

31AHRZ

31AHRZ

TEMP

RANGE

(°C)

-10 to +100 28 Ld 5x5

-10 to +100 28 Ld 5x5

PACKAGE

(Pb-Free)

TQFN

TQFN (Tape
and Reel)

PKG.

DWG. #

L28.5x5B

L28.5x5B

1

CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.

1-888-INTERSIL or 1-888-468-3774

| Intersil (and design) is a registered trademark of Intersil Americas Inc.

Copyright Intersil Americas Inc. 2008, 2009. All Rights Reserved

All other trademarks mentioned are the property of their respective owners.

ISL88731A

VDDSMB

SDA
SCL

CSSP
CSSN

IC O MP

CSOP
CSON

VFB

VCOMP

SMBUS

LEVEL

SHIFTER

20x

LEVEL

SHIFTER

20x

500k

11

6

6

100k

EN

DACS

DACI

DACV
DACS

DACI

EN

­+

­+

GMS

GMI

DACV
DACS
DACI

DACV

DCIN

LINEAR

REGU LATOR

+

GMV

-

BUFF

LVB

VDDP

CSO

LVB

VCC

REF

+

-

EN

DC/DC

CONVERTER

CSSP

REFERENCE

VREF

ACOK

ACIN
IC M

BOOT

UGATE

PHASE

VDDP
LGATE

PGND

GND

AC ADAPTER

AGND

FIGURE 1. FUNCTIONAL BLOCK DIAGRAM

RS1

CSSNCSSP

UGATE
ACIN
DCIN

PHASE

ISL88731A

BOOT

LGATE

CSOP
CSON

ICOMP

VCOMP

VDDP

VREF

VCC

GND

VFB

PGND

ACOK

ICM

SDA

SCL

VDDSMB

TO SYSTEM

RS2

HOST

TO BATTERY

PGND

AGND

FIGURE 2. TYPICAL APPLICATION CIRCUIT

2

FN6738.1

January 7, 2009

ISL88731A

Absolute Maximum Ratings

DCIN, CSSP, CSSN, CSOP, CSON, VFB . . . . . . . . . .-0.3V to +28V

CSSP-CSSN, CSOP-CSON, PGND-GND. . . . . . . . . -0.3V to +0.3V

PHASE to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -6V to +30V

BOOT to GND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3V to +33V

BOOT to PHASE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3V to +6V

UGATE . . . . . . . . . . . . . . . . . . . . . . .PHASE - 0.3V to BOOT +0.3V

LGATE . . . . . . . . . . . . . . . . . . . . . . . .PGND - 0.3V to VDDP +0.3V

ICOMP, VCOMP, VREF, to GND . . . . . . . . . . . . -0.3V to VCC +0.3V

VDDSMB, SCL, SDA, ACIN, ACOK . . . . . . . . . . . . . . .-0.3V to +6V

VDDP, ICM, VCC to GND, VDDP to PGND. . . . . . . . . .-0.3V to +6V

CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product relia bility and
result in failures not covered by warranty.

NOTES:

is measured with the component mounted on a highly effective thermal conductivity test board on free air. See T ech Brief TB379 for det ails.

1. θ

JA

2. For θ

, the “case temp” location is the center of the exposed metal pad on the package underside.

JC

Thermal Information

Thermal Resistance (Typical, Notes 1, 2) θJA (°C/W) θJC (°C/W)

QFN Package. . . . . . . . . . . . . . . . . . . . 39 9.5

Junction Temperature Range. . . . . . . . . . . . . . . . . .-55°C to +150°C

Operating Temperature Range . . . . . . . . . . . . . . . .-10°C to +100°C

Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65°C to +150°C

Pb-Free Reflow Profile. . . . . . . . . . . . . . . . . . . . . . . . .see link below

http://www.intersil.com/pbfree/Pb-FreeReflow.asp

Electrical Specifications DCIN = CSSP = CSSN = 18V, CSOP = CSON = 12V, VDDP = 5V, BOOT-PHASE = 5.0V, GND = PGND = 0V,

CVDDP = 1µF, IVDDP = 0mA, T
at +25°C, unless otherwise specified. T emperature limits est ablished by characterization and are not production
tested.

PARAMETER CONDITIONS MIN TYP MAX UNITS

CHARGE VOLTAGE REGULATION

Battery Full Charge Voltage and Accuracy ChargeVoltage = 0x41A0 16.716 16.8 16.884 V

ChargeVoltage = 0x3130 12.529 12.592 12.655 V

ChargeVoltage = 0x20D0 8.350 8.4 8.450 V

ChargeVoltage = 0x1060 4.163 4.192 4.221 V

Battery Undervoltage Lockout Trip Point
for Trickle Charge

Battery Undervoltage Lockout Trip Point
Hysteresis

CHARGE CURRENT REGULATION

CSOP to CSON Full-Scale Current-Sense
Voltage

Charge Current and Accuracy RS2 = 10mΩ (see Figure 2)

Charge Current Gain Error Based on charge current = 128mA and 8.064A -1.6 1.4 %
CSOP/CSON Input Voltage Range 0 19 V

VFB rising 2.55 2.7 2.85 V

ChargingCurrent = 0x1f80

RS2 = 10mΩ (see Figure 2)
ChargingCurrent = 0x0f80

RS2 = 10mΩ (see Figure 2)
ChargingCurrent = 0x0080

= -10°C to +100°C. Parameters with MIN and/or MAX limits are 100% tested

A

-0.5 0.5 %

-0.5 0.5 %

-0.6 0.6 %

-0.7 0.7 %

100 250 400 mV

78.22 80.64 83.06 mV

7.822 8.064 8.306 A

-3 3 %

3.809 3.968 4.126 A

-4 4 %

64 128 220 mA

3

FN6738.1

January 7, 2009

ISL88731A

Electrical Specifications DCIN = CSSP = CSSN = 18V, CSOP = CSON = 12V, VDDP = 5V, BOOT-PHASE = 5.0V, GND = PGND = 0V,

CVDDP = 1µF, IVDDP = 0mA, T
at +25°C, unless otherwise specified. T emperature limits est ablished by characterization and are not production
tested. (Continued)

PARAMETER CONDITIONS MIN TYP MAX UNITS

Battery Quiescent Current Adapter present, not charging,

I

CSOP

V

PHASE

+ I

CSON

= V

+ I

CSON

Adapter Absent
I

Adapter Quiescent Current I

+ I

CSOP

V

PHASE

DCIN+ICSSP+ICSSN

V

ADAPTER

+ I

CSON

= V

CSON

= 8V to 26V, V

INPUT CURRENT REGULATION

CSSP to CSSN Full-Scale Current-Sense

CSSP = 19V 106.7 110 113.3 mV

Voltage
Input Current Accuracy RS1 = 10mΩ (see Figure 2)

Adapter Current = 11004mA or 3584mA
RS1 = 10mΩ (see Figure 2)

Adapter Current = 2048mA
Input Current Limit Gain Error Based on InputCurrent = 1024mA and 11004mA -1.5 1.5 %
Input Current Limit Offset -1 1 mV
CSSP/CSSN Input Voltage Range 826V
ICM Gain V

CSSP-CSSN

ICM Offset Based on V
ICM Accuracy V

ICM Max Output Current V

CSSP-CSSN

V

CSSP-CSSN

V

CSSP-CSSN
CSSP-CSSN

= 110mV 19.8 20 20.2 V/V

CSSP-CSSN

= 110mV -2.5 2.5 %
= 55mV or 35mV -4 4 %
= 20mV -8 8 %
= 0.1V 500 µA

SUPPLY AND LINEAR REGULATOR

DCIN, Input Voltage Range 826V
VDDP Output Voltage 8.0V < V
VDDP Load Regulation 0 < I

VDDP

< 28V, no load 4.9 5.1 5.3 V

DCIN

< 30mA 35 100 mV
VDDSMB Range 2.7 5.5 V
VDDSMB UVLO Rising 2.4 2.5 2.6 V
VDDSMB UVLO Hysteresis 100 150 200 mV
VDDSMB Quiescent Current VDDP = SCL = SDA = 5.5V 20 27 µA

V REFERENCE

VREF Output Voltage 0 < I

< 300µA 3.1 3.2 3.3 V

VREF

ACOK

ACOK Sink Current V
ACOK Leakage Current V

= 0.4V, ACIN = 1.5V 2 8 mA

ACOK

= 5.5V, ACIN = 2.5V 1 µA

ACOK

ACIN

ACIN rising Threshold 3.1 3.2 3.3 V
ACIN Threshold Hysteresis 40 60 90 mV
ACIN Input Bias Current -1 1 µA

= -10°C to +100°C. Parameters with MIN and/or MAX limits are 100% tested

A

135 400 µA

PHASE

= V

CSOP

+ I

CSSP

= V

+ I

DCIN

+ I

CSSN

= 19V, V

FB

ACIN

= 5V

-1 0.2 4 µA

PHASE

= V

CSOP

+ I

CSSP

= 19V, V

+ I

CSSN

DCIN

+ I

= 0V

FB

310mA

BATTERY

4V to 16.8V

-3 3 %

-5 5 %

= 110mV and 20mV -1.5 1.5 mV

4

FN6738.1

January 7, 2009

ISL88731A

Electrical Specifications DCIN = CSSP = CSSN = 18V, CSOP = CSON = 12V, VDDP = 5V, BOOT-PHASE = 5.0V, GND = PGND = 0V,

CVDDP = 1µF, IVDDP = 0mA, T
at +25°C, unless otherwise specified. T emperature limits est ablished by characterization and are not production
tested. (Continued)

PARAMETER CONDITIONS MIN TYP MAX UNITS

SWITCHING REGULATOR

Frequency 330 400 440 kHz
BOOT Supply Current UGATE High 170 290 400 µA
PHASE Input Bias Current V
UGATE ON-Resistance Low I
UGATE ON-Resistance High I
LGATE ON-Resistance High I
LGATE ON-Resistance Low I

= 28V, V

DCON

= -100mA (Note 4) 0.9 1.6 Ω

UGATE

= 10mA (Note 4) 1.4 2.5 Ω

UGATE

= +10mA (Note 4) 1.4 2.5 Ω

LGATE

= -100mA (Note 4) 0.9 1.6 Ω

LGATE

Dead Time Falling UGATE to rising LGATE or

falling LGATE to rising UGATE

ERROR AMPLIFIERS

GMV Amplifier Transconductance 200 250 300 µA/V
GMI Amplifier Transconductance 40 50 60 µA/V
GMS Amplifier Transconductance 40 50 60 µA/V
GMI/GMS Saturation Current 15 21 25 µA
GMV Saturation Current 10 17 30 µA
ICOMP, VCOMP Clamp Voltage 0.25V < V

ICOMP, VCOMP

LOGIC LEVELS

SDA/SCL Input Low Voltage VDDSMB = 2.7V to 5.5V 0.8 V
SDA/SCL Input High Voltage VDDSMB = 2.7V to 5.5V 2 V
SDA/SCL Input Bias Current VDDSMB = 2.7V to 5.5V -1 1 µA
SDA, Output Sink Current V

= 0.4V 7 15 mA

SDA

= -10°C to +100°C. Parameters with MIN and/or MAX limits are 100% tested

A

CSON

= V

= 20V 0 2 µA

PHASE

35 50 80 ns

< 3.5V 200 300 400 mV

SMBus Timing Specification VDDSMB = 2.7V TO 5.5V

PARAMETERS SYMBOL CONDITIONS MIN TYP MAX UNITS

SMBus Frequency FSMB 10 100 kHz
Bus Free Time TBUF 4.7 µs
Start Condition Hold Time from SCL THD:STA 4 µs
Start Condition Setup Time from SCL TSU:STA 4.7 µs
Stop Condition Setup Time from SCL TSU:STO 4 µs
SDA Hold Time from SCL THD:DAT 300 ns
SDA Setup Time from SCL TSU:DAT 250 ns
SCL Low Timeout (Note 3) TTIMEOUT 22 25 30 ms
SCL Low Period TLOW 4.7 µs
SCL High Period THIGH 4 µs
Maximum Charging Period Without a SMBus Write to

ChargeVoltage or ChargeCurrent Register

NOTES:

3. If SCL is low for longer than the specified time, the charger is disabled.

4. Limits established by characterization and are not production tested.

5

140 180 220 s

FN6738.1

January 7, 2009

ISL88731A

Typical Operating Performance DCIN = 20V, 3S2P Li-Battery, T

5.15

5.10

5.05

5.00

VDDP (V)

4.95

4.90

4.85
020406080100

VDDP LOAD CURRENT (mA)

FIGURE 3. VDD LOAD REGULATION

15

10

5

0

-5

ICM ACCURACY (%)

-10

3.23

3.22

3.21

3.20

VREF (V)

3.19

3.18

3.17

13.0

12.5

12.0

11.5

11.0

BATTERY VOLTAGE

10.5

= +25°C, unless otherwise noted.

A

0 50 100 150 200

I VREF (µA)

FIGURE 4. VREF LOAD REGULATION

VCHG (V)

ICHG (A)

1.0%

0.5%

0.0%

-0.5%

-1.0%

3.5

3.0

2.5

2.0

1.5

1.0

0.5

BATTERY CURRENT

-15
123 567

48

ADAPTER CURRENT (A)

FIGURE 5. ICM ACCURACY vs AC-ADAPTER CURRENT

VCOMP

ICOMP

CHARGE

CURRENT

INDUCTOR
CURRENT

FIGURE 7. CHARGE ENABLE

10.0
0 20406080100120140160

TIME (MINUTES)

0.0

FIGURE 6. TYPICAL CHARGING VOLTAGE AND CURRENT

ICOMP

VCOMP

CHARGE

CURRENT

INDUCTOR
CURRENT

FIGURE 8. CHARGE DISABLE

6

FN6738.1

January 7, 2009

ISL88731A

Typical Operating Performance DCIN = 20V, 3S2P Li-Battery, T

UGATE

PHASE

FIGURE 9. SWITCHING WAVEFORMS AT DIODE EMULATION

CSON/
V

BATTERY

LGATE

INDUCTOR
CURRENT

FIGURE 10. SWITCHING WAVEFORMS IN CC MODE

= +25°C, unless otherwise noted. (Continued)

A

UGATE

INDUCTOR
CURRENT

LGATE

PHASE

CSON/
V

BATTERY

BATTERY
CURRENT

FIGURE 11. BATTERY REMOVAL

SYSTEM
LOAD

BATTERY
VOLTAGE

CHARGE
CURRENT

ADAPTER
CURRENT

FIGURE 13. LOAD TRANSIENT RESPONSE

BATTERY
CURRENT

FIGURE 12. BATTERY INSERTION

100

95

90

85

80

75

70

04 8

16.8V

BATTERY

12.6V

BATTERY

8.4V

BATTERY

4.2V

BATTERY

26

CHARGE CURRENT (A)

FIGURE 14. EFFICIENCY vs CHARGE CURRENT AND

BATTERY VOLTAGE (EFFICIENCY DC

= 20V)

IN

7

FN6738.1

January 7, 2009