Datasheet MAX1665XESA, MAX1665VESA, MAX1665SESA Datasheet (Maxim)

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General Description

The MAX1665 provides protection against overvoltage,
undervoltage, overcharge current, and overdischarge
current for 2-cell to 4-cell lithium-ion (Li+) battery packs.
Very low operating current ensures that cells are not
overdischarged during long storage periods.

The MAX1665 controls two external N-channel MOSFETs
to limit the charge and discharge voltages. Charging is
allowed when the per-cell voltage is below +4.3V. When
the voltage on any cell rises above +4.3V (overvoltage
limit), the MAX1665 turns off the charge MOSFET. This
safety feature prevents overcharge of any cell within the
battery pack.

Discharge is allowed when the per-cell voltage is above
+2.5V (undervoltage limit). If the voltage across any cell
falls below +2.5V, the MAX1665 turns off the discharge
MOSFET. This safety feature prevents overdischarge of
any cell within the battery pack.

Charging and discharging are allowed if the voltage
between PKN and BN is less than 250mV. This safety fea­ture prevents excessive pack current.

Applications

Lithium-Ion Battery Packs

____________________________Features

♦ Complete Protection Against:

Cell Overvoltage
Cell Undervoltage

♦ Pack Protection for Excessive Charge and

Discharge

♦ Very Low Supply Current: 16µA typ

♦ Low Standby Current: 1µA max

♦ Matched Cell Input Bias Current (<500pA)

Preserves Cell Balance

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

________________________________________________________________ Maxim Integrated Products 1

B1P

PKN

BN

1

2

87I.C. [B3P]

B2PDSG

CHG

I.C. (B4P)

NOTES: I.C. = INTERNAL CONNECTION. MAKE NO CONNECTIONS TO THIS PIN.
( ) ARE FOR THE MAX1665X.
[ ] ARE FOR THE MAX1665V AND MAX1665X.

SO

TOP VIEW

3

4

6

5

MAX1665S
MAX1665V
MAX1665X

MAX1665X

B4P B3P

DSG

B2P

B1P

PKN

(-)

(+)

CHG

BN

Typical Operating Circuit

19-1605; Rev 0; 1/00

Pin Configuration

Ordering Information

PART

MAX1665SESA

MAX1665VESA

MAX1665XESA -40°C to +85°C

-40°C to +85°C

-40°C to +85°C

TEMP. RANGE

PIN-

PACKAGE

8 SO

8 SO

8 SO

CELL

COUNT

2

3

4

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

ELECTRICAL CHARACTERISTICS

(V

B2P

= 8V (MAX1665S), V

B3P

= 12V (MAX1665V), V

B4P

= 16V (MAX1665X), TA= 0°C to +85°C, unless otherwise noted. Typical

values are at T

A

= +25°C.)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

B4P to PKN (MAX1665X)........................................-0.3V to +24V

B3P to PKN (MAX1665V)........................................-0.3V to +18V

B2P to PKN (MAX1665S)........................................-0.3V to +12V

B1P to PKN, B2P to B1P, B3P to B2P, B4P to B3P...-0.3V to +6V
CHG to PKN, DSG to BN

MAX1665S............................................-0.3V to (V

B2P

+ 0.3V)

MAX1665V............................................-0.3V to (V

B3P

+ 0.3V)

MAX1665X............................................-0.3V to (V

B4P

+ 0.3V)

B2P to BN (MAX1665S)..........................................-0.3V to +12V

B3P to BN (MAX1665V)..........................................-0.3V to +18V

B4P to BN (MAX1665X)..........................................-0.3V to +24V

Continuous Power Dissipation (T

A

= +70°C)

8-Pin SO (derate 5.88mW/°C above +70°C)...............471mW

Operating Temperature Range ...........................-40°C to +85°C

Junction Temperature......................................................+150°C

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

Lead Temperature (soldering, 10s) .................................+300°C

MAX1665SESA, V

B1P

= 4V nA

310

MAX1665X

MAX1665V

MAX1665S

V

PKN

= ±300mV

V

PKN

= ±300mV

(Note 1)

V

CHG

= V

PKN

+ 3.0V

CHG = PKN, DSG = BN

Cell voltage rising

I

DSG

= -1µA

VBN- V

PKN

MAX1665X, I

OUT

= 100µA, V

B4P

= 24V,

VBN= 100mV

CONDITIONS

I

BIAS

Input Bias Current (Note 3)

MAX1665VESA, V

B1P

= 4V, V

B2P

= 8V

nA

310

MAX1665XESA, V

B1P

= 4V, V

B2P

= 8V,

V

B3P

= 12V

310

ms

135

t

OFF

Overcurrent Sampling - t

OFF

ms

8.2

t

ON

Overcurrent Sampling - t

ON

mA

0.5 2

I

OL

CHG Output Sink Current

mA

10 25

I

OH

CHG, DSG Output Source
Current

V

VBN+ 0.1

V

DSGL

DSG Output Voltage Low

V

17 20

DSG Output Voltage High
(Note 2)

V

420

V

B4P

B4P Voltage Range

V

4 15

V

B3P

V

410

V

B2P

B2P Voltage Range

B3P Voltage Range

ms

10

t

IO

Overcurrent Detection Delay

ms

200

t

UV

Overvoltage/Undervoltage
Delay

mV

5

V

CH2

Overcurrent Hysteresis

mV

±200 ±250 ±300

V

CH

Overcurrent Sense Threshold

V

4.26 4.3 4.34

V

OV

Overvoltage Threshold

V

0.10

V

CE

Overvoltage Hysteresis

V

2.4 2.5 2.6

V

UV

Undervoltage Threshold

mV

0 18 30

V

RE

Undervoltage RESET

UNITSMIN TYP MAXSYMBOLPARAMETER

I

OUT

= 100µA V

V

B2P

- 1.8 V

B2P

- 0.54

CHG, DSG Output Voltage High

I

CHG

= -100µA V

V

B3P

- 1.8 V

B3P

- 0.54

MAX1665S

MAX1665V

V

PKN

+ 0.1

V

CHGL

V

B4P

- 1.8 V

B4P

- 0.54

MAX1665X

CHG Output Voltage Low

V

DSG

= V

BN

+ 3.0V µA

0.5 2

I

OL

DSG Output Sink Current

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

_______________________________________________________________________________________ 3

ELECTRICAL CHARACTERISTICS (continued)

(V

B2P

= 8V (MAX1665S), V

B3P

= 12V (MAX1665V), V

B4P

= 16V (MAX1665X), TA= 0°C to +85°C, unless otherwise noted. Typical

values are at T

A

= +25°C.)

ELECTRICAL CHARACTERISTICS

(V

B2P

= 8V (MAX1665S), V

B3P

= 12V (MAX1665V), V

B4P

= 16V (MAX1665X), TA= -40°C to +85°C, unless otherwise noted.) (Note 6)

Note 1: Applies to the differential voltage measured on any cell.
Note 2: DSG is internally clamped to a maximum of 20V to protect the external MOSFET (V

GS

).

Note 3: Guaranteed by design.
Note 4: The input bias matching between cells is measured with a 4V voltage between cells.
Note 5: At least one cell is <V

UV

.

Note 6: Specifications to -40°C are guaranteed by design, not production tested.

MAX1665SESA, V

B1P

= 4V

nA

10

MAX1665X

DSG = CHG = low

MAX1665V

MAX1665S

V

DSG

= VBN+ 0.3V

V

CHG

= V

PKN

+ 0.3V

CHG = PKN, DSG = BN

Cell voltage rising

I

DSG

= -1µA

VBN- V

PKN

MAX1665X, I

OUT

= 100µA, V

B4P

= 24V,

VBN= 100mV

CONDITIONS

I

BIAS

Input Bias Current (Note 3)

MAX1665VESA, V

B1P

= 4V, V

B2P

= 8V

10

MAX1665XESA, V

B1P

= 4V, V

B2P

= 8V,

V

B3P

= 12V

10

V

4.7

V

UVLO

Undervoltage Lockout

µA

30

I

CC

Supply Current

µA

0.2

I

OL

DSG Output Sink Current

mA

0.2

I

OL

CHG Output Sink Current

mA

10

I

OH

CHG, DSG Output Source
Current

V

VBN+ 0.1

V

DSGL

DSG Output Voltage Low

V

20

DSG Output Voltage High
(Note 2)

V

420

V

B4P

B4P Voltage Range

V

4 15

V

B3P

V

410

V

B2P

B2P Voltage Range

B3P Voltage Range

mV

±180 ±320

V

CH

Overcurrent Sense Threshold

V

4.20 4.24

V

OV

Overvoltage Threshold

V

2.4 2.6

V

UV

Undervoltage Threshold

mV

0 30

V

RE

Undervoltage RESET

UNITSMIN TYP MAXSYMBOLPARAMETER

I

OUT

= 100µA V

V

B2P

- 2 V

B2P

- 0.5

CHG, DSG Output Voltage High

I

CHG

= -100µA V

V

B3P

- 2 V

B3P

- 0.5

MAX1665S

MAX1665V

V

PKN

+ 0.1

V

CHGL

V

B4P

- 2 V

B4P

- 0.5

MAX1665X

CHG Output Voltage Low

(Note 5) µA

2

I

LP

Standby Mode Current

DSG = CHG = low

(Note 5)

CONDITIONS

(Notes 3, 4) pA

±500

∆I

BIAS

V

4.0 4.7

V

UVLO

Undervoltage Lockout

µA

0.7 1

I

LP

Standby Mode Current

µA

16 25

I

CC

Supply Current

UNITSMIN TYP MAXSYMBOLPARAMETER

Input Bias Current Matching

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

4 _______________________________________________________________________________________

Typical Operating Characteristics

(TA = +25°C, unless otherwise noted.)

4.14

4.18

4.26

4.22

4.30

4.34

-40 10-15 35 60 85

OVERVOLTAGE THRESHOLD vs.

TEMPERATURE

MAX1665 toc01

TEMPERATURE (°C)

THRESHOLD VOLTAGE (V)

VBN

- V

PKN

HYSTERESIS

2.46

2.47

2.49

2.48

2.50

2.51

-40 10-15 35 60 85

UNDERVOLTAGE THRESHOLD vs.

TEMPERATURE

MAX1665 toc02

TEMPERATURE (°C)

UNDERVOLTAGE THRESHOLD (V)

V

BN

- V

PKN

240

243

249

246

252

255

-40 10-15 35 60 85

OVERCURRENT THRESHOLD vs.

TEMPERATURE

MAX1665 toc03

TEMPERATURE (°C)

OVERCURRENT THRESHOLD (mV)

VBN - V

PKN

-260

-254

-256

-258

-252

-250

-248

-246

-244

-242

-240

-40 10-15 35 60 85

OVERDISCHARGE THRESHOLD

vs. TEMPERATURE

MAX1665 toc04

TEMPERATURE (°C)

OVERDISCHARGE THRESHOLD (mV)

V

BN - VPKN

16.0

16.4

17.2

16.8

17.6

18.0

2.5 3.53.0 4.0 4.5 5.0

QUIESCENT CURRENT
vs. SUPPLY VOLTAGE

MAX1665 toc07

SUPPLY VOLTAGE PER CELL (V)

QUIESCENT CURRENT (µA)

NORMALIZED TO ONE CELL

16.0

16.5

17.0

17.5

18.0

SUPPLY CURRENT

vs. TEMPERATURE

MAX1665 toc05

TEMPERATURE (°C)

SUPPLY CURRENT (µA)

-40 20 40-20 0 60 80 100

0.5

0.6

0.8

0.7

0.9

1.0

-40 0-20 20 40 60 80 100

STANDBY MODE CURRENT

vs. TEMPERATURE

MAX1665 toc06

TEMPERATURE (°C)

STANDBY CURRENT (µA)

CHG

2V/div

50ms/div

CONTINUOUS OVERCHARGE CONDITION

MAX1665 toc08

DSG

2V/div

50ms/div

CONTINUOUS OVERDISCHARGE CONDITION

MAX1665 toc09

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

_______________________________________________________________________________________ 5

FUNCTION

1, 8 1 Internally Connected. Make no connection to this pin.

— —

Cell 4 Positive Input. Connect to the positive terminal of the fourth
series Li+ cell.

2 2

Discharge Control Output. Drives the gate of an external N-channel
MOSFET to control the discharge path.

3 3

Charge Control Output. Drives the gate of an external N-channel
MOSFET to control the charge path.

7 7

Cell 2 Positive Input. Connect to the positive terminal of the second
series Li+ cell.

6 6

Cell 1 Positive Input. Connect to the positive terminal of the first
series Li+ cell.

5 5 Connect to the negative terminal of the first series Li+ cell.

4 4 Pack Negative Input

— 8

Cell 3 Positive Input. Connect to the positive terminal of the third
series Li+ cell.

Pin Description

—

1

2

3

7

6

5

4

8

NAME

I.C.

B4P

DSG

CHG

B2P

B1P

BN

PKN

B3P

MAX1665VMAX1665S MAX1665X

PIN

Table 1. Functionality Truth Table for VBN< V

PKN

+ 0.018V (Discharge Mode)

*Assuming no load on CHG or DSG.

0

1

1

1 1

25Yes

NoLow

Gated

Low

Low1

10

0

1

0

1

1

0

0 1

25

1No

Yes

NoLow

Gated

Low

Low

Gated

Low0

1

10

0

0

UNDERVOLTAGE

0

1

0

OVERVOLTAGE

0

0

1 25

1

25

MAX

SUPPLY

CURRENT*

(µA)

GATE

CLOCKED

No

No

NoHigh

Low

High

DSG

Low

Low

High

CHG

DISCHARGE

OVERCURRENT

0

0

00

0

0

CHARGE

OVERCURRENT

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

6 _______________________________________________________________________________________

Figure 1. State Diagram

_______________Detailed Description

The MAX1665S, MAX1665V, and MAX1665X supervise
the charging and discharging processes on Li+ cells.
Designed for 2, 3, and 4-cell applications, these devices
monitor the voltage across each cell to provide protec­tion against overcurrent, overvoltage, and undervoltage.

Figure 1 shows the MAX1665 state diagram. Two con­trol pins, CHG and DSG, drive the gates of two series­connected external N-channel MOSFETs, enabling/
disabling the charging/discharging process as neces­sary (see Typical Operating Circuit). The voltages at
B1P, B2P, B3P, and B4P are measured differentially

Table 2. Functionality Truth Table for VBN> V

PKN

+ 0.018V (Charge Mode)

*Assuming no load on CHG or DSG.

0

1

1

1 25

25No

NoHigh

High

Low

Low0

01

1

1

0

1

1

0

0 25

25

25No

Yes

YesGated

Gated

High

Gated

Gated

Low0

0

01

1

0

UNDERVOLTAGE

0

1

0

OVERVOLTAGE

0

0

1 25

25

25

MAX

SUPPLY

CURRENT*

(µA)

GATE

CLOCKED

No

No

NoHigh

High

High

DSG

Low

High

High

CHG

DISCHARGE

OVERCURRENT

0

0

00

0

0

CHARGE

OVERCURRENT

POWER

ON

POWER

SLEEP

DSG = 0

ON

CHG = 0

CHARGE = 0

NORMAL

DSG = 1

CHG = 1

SUPPLIES

ON
DSG = 0
CHG = 0

∆T =

2.4ms

CHARGE = 1 RDY = 1

UV = 0
OV = 0

NORMAL

PULSE OFF

DSG = *
CHG = *

START

COUNTER

DSG = 0
CHG = 0

∆T =

96ms

∆T =

2.4ms

NORMAL

PULSE ON

DSG = 1
CHG = 1

START-UP

ZCHK
DSG = 0
CHG = 0

∆T =

6.4ms

∆T =

160µs

NORMAL

ZCHK
DSG = 1
CHG = 1

START-UP
MEASURE

DSG = 0
CHG = 0

∆T =

160µs

∆T =

640µs

SHORT = 1 SHORT = 1

WAIT FOR

BLANK = 0

DSG = 0
CHG = 0

NORMAL

MEASURE

DSG = 1
CHG = 1

∆T =

2.4ms

∆T =
640µs

UV = 0
OV = 1

UV = 1
OV = 0

UV = 1
OV = 1

* = 0 FOR OVERCURRENT FAULT; 1 OTHERWISE

OV

DSG = 1

CHG = 0

DSG = 1

CHG = 1

OV & UV

DSG = 1

CHG = 0

∆T =

2.4ms

UV

∆T =

2.4ms

CHARGE = 0 CHARGE = 0 CHARGE = 0 CHARGE = 0

∆T =

2.4ms

OV

PULSE OFF

DSG = 1
CHG = 0

UV

PULSE OFF

DSG = *
CHG = *

OV & UV

PULSE OFF

DSG = 1
CHG = 0

∆T =

96ms

∆T =

96ms

∆T =

96ms

OV

PULSE ON

DSG = 1
CHG = 0

UV

PULSE ON

DSG = 1
CHG = 1

OV & UV

PULSE ON

DSG = 1

CHG = 0

∆T =

6.4ms

∆T =

6.4ms

∆T =

6.4ms

OV

ZCHK
DSG = 1
CHG = 0

UV

ZCHK
DSG = 1
CHG = 1

OV & UV

ZCHK
DSG = 1
CHG = 0

∆T =

160µs

∆T =

160µs

∆T = 160µs

OV

MEASURE

DSG = 1
CHG = 0

SHORT = 1

UV

MEASURE

DSG = 1
CHG = 1

SHORT = 1

OV & UV

MEASURE

DSG = 1

CHG = 0

∆T =
640µs

∆T =
640µs

∆T =
640µs

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

_______________________________________________________________________________________ 7

across each cell to determine if the voltage levels are
within operating range.

As depicted in the typical operating circuit, when CHG
and DSG are high, the MOSFETs are on, allowing the
cells to charge or discharge. However, when the
charge or discharge current becomes excessive, the
device turns off the FETs, enters a standby mode, and
periodically samples the current to determine if the fault
condition is removed. The MAX1665 does not sample
the current directly, but rather measures the differential
voltage across BN and PKN produced by the charge or
discharge current flowing through the drain-to-source
resistance of the MOSFETs. A preset voltage threshold
is used to prevent excess current flow (see Electrical
Characteristics).

In operating mode, all of the MAX1665 versions con­sume less than 25µA of quiescent current, allowing
long-term battery storage without significantly affecting
battery life. In standby mode, these devices consume
less than 1µA of quiescent current.

Overvoltage Protection

When any individual cell voltage rises above VOV(over­voltage limit), the charge MOSFET control pin (CHG) is
driven to PKN, thereby disconnecting the charger from
the cells. The MAX1665 measures each cell of the pack
differentially to prevent overcharging on a cell-by-cell
basis. The charging process resumes when the highest
cell voltage drops below VOV- 100mV (see Typical
Operating Circuit).

Undervoltage/Overdischarge Protection

Discharge can occur whenever the voltage of each cell
is above the undervoltage threshold voltage (VUV, typi­cally 2.50V). If the voltage on any of the cells falls
below VUV, CHG latches to PKN and DSG latches to
BN. Quiescent current falls to under 1µA as the device
enters the standby mode. The latch resets when BN
exceeds PKN by 18mV.

During charge mode, when BN is greater than PKN, the
latch is held in reset, which disables the undervoltage
comparator feature and allows charging on the cells.
During the initialization process, as cells are connected
to the MAX1665, the device considers this a low-volt­age condition and disables CHG and DSG until a
charging source is applied to create at least an 18mV
differential between BN and PKN.

During long-term storage, the battery will self-dis­charge until it reaches the undervoltage threshold.
When this happens, the MAX1665 enters standby
mode. Normal operating mode resumes when a charg­er is connected, causing BN to rise 18mV above PKN.

Overcurrent Protection

When the MAX1665 detects overcurrent in the system,
it disables the charge or discharge process by con­necting CHG to PKN and DSG to BN, turning off the
external MOSFETs (see Typical Operating Circuit). In
charge mode, the MAX1665 detects overcharge when
the voltage from BN to PKN exceeds +250mV. In dis­charge mode, overdischarge occurs when the differen­tial voltage is less than -250mV. During any overcurrent
condition, CHG and DSG are gated at 12Hz until the
overcurrent is removed.

If both an overvoltage and overcharge condition exist,
the overvoltage condition takes priority. Likewise, if
undervoltage and overdischarge conditions exist, the
overdischarge condition takes priority. For more
details, see Tables 1 and 2.

Cell Current Balancing

When the battery cells are matched, the MAX1665
draws zero current from the intermediate nodes. The
MAX1665 draws current from the top terminal only.
Figure 2 shows a simplified diagram of the voltage
sampling scheme. The following equations show that,
for balanced cells, the differential discharge currents
are zero:

B4P: I4= 3ICB+ V4/ R = 4V4/ R = BAT4 current

B3P: I3= I3P+ I4= BAT3 current

I3P+ ICB= V3/ R ⇒ I3P= V3/ R - V4/ R

I3= I4+ (V3- V4) / R = (3V4+ V3) / R

B2P: I2= I2P+ I3= BAT2 current

I2P+ ICB= V2/ R ⇒ I2P= V2/ R - V4/ R

I2= I3 + V2/ R - V4/ R = I4+ (V3- V4) / R +

(V2- V4) / R = (2V4+ V3+ V2) / R

B1P: I1= I1P+ I2= BAT1 current

I1P+ ICB= V1 / R ⇒ I1P= V1/ R - V4/ R

I1= I2+ V1/ R - V4/ R = I4+ (V3- V4) / R +

(V2- V4) / R + (V1- V4) / R

= (V4+ V3+ V2+ V1) / R

when V1= V2= V3= V4, I1P= I2P= I3P= 0 and I1=

I2= I3= I4= 4V4/ R.

Due to process variations, the MAX1665 does draw a
minute current (70nA ~ 150nA) from the intermediate
node even when the cells are matched. This current
difference exists in the sampling mode, which is 1/32 of
the whole time period, making the average of this cur­rent 2nA to 5nA.

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

8 _______________________________________________________________________________________

Applications Information

Choosing an External MOSFET

The external N-channel MOSFETs act as gated switch­es to enable or disable the charging/discharging
process. CHG and DSG control the gate of these exter­nal MOSFETs to prevent damage to the

Li+ cells. For

overcurrent conditions, the voltage at DSG equals the
voltage at BN, thereby reducing all current flow, includ­ing the path through the body diode of the
N-channel MOSFET. Note that the MAX1665X clamps
the V

GS

voltage to a maximum of 20V.

The IRF7101 is a low-cost, dual N-channel MOSFET
that is available in a small 8-pin SO package.
Depending on the maximum charge and discharge
rates, use different MOSFETs to optimize each applica­tion. Table 3 summarizes recommended MOSFETs.

2, 3, and 4-Cell Applications

Figures 3 through 5 depict circuits for 2, 3, and 4-cell
applications. Note that the two series MOSFETs (IRF7101
dual N-channel MOSFETs) are oriented to prevent body
diode current flow. The indicated polarity symbols show
the connection for the external source required to charge
the Li+ cells. This external charger source also supplies
the gate drive to the MOSFETs through pack + voltage /
pack.

DUAL N-CHANNEL

MOSFETs

IRF9956

FDS6990A

Si9936 0.050

0.018

0.10

TYPICAL

R

DS(ON)

(Ω)

±20

±20

±20

MAX V

GS

(V)

Table 3. Recommended MOSFETs

Figure 2. Sampling Mode Equivalent Circuit

Figure 3. Typical 2-Cell Operating Circuit

BP4

I

BP3
I

3

BP2

I

2

BP1

I

1

4

I

3P

I

2P

I

+

1P

V

1

B1P1

R

V

4

I

CB

+

R

V

2

V

1

R

B2P1

V

4

I

CB

R

+

V

3

V

2

R

B3P1

V

4

I

CB

R

+

V

4

V

3

R

+

V

4

+

V

3

+

V

2

+

V

1

RRR

V

4

R

PACK+

OVERDISCHARGE

PROTECTION

OVERCHARGE

PROTECTION

PACK-

CELL 2

CELL 1

IRF7101

IRF7101

1

8

7

6

5

2

3

4

I.C.

I.C.

B2P

B1P

BN

DSG

CHG

PKN

MAX1665S

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

_______________________________________________________________________________________ 9

PACK+

Figure 4. Typical 3-Cell Operating Circuit

Figure 5. Typical 4-Cell Operating Circuit

OVERDISCHARGE

PROTECTION

OVERCHARGE

PROTECTION

CELL 3

CELL 2

CELL 1

IRF7101

IRF7101

1

I.C.

8

B3P

7

B2P

6

B1P

5

MAX1665V

BN

2

DSG

3

CHG

PACK+

CELL 4

CELL 3

CELL 2

CELL 1

OVERDISCHARGE

PROTECTION

OVERCHARGE

PROTECTION

IRF7101

IRF7101

1

B4P

8

B3P

7

B2P

6

B1P

5

MAX1665X

BN

2

DSG

3

CHG

PACK-

4

PKN

PACK-

4

PKN

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

10 ______________________________________________________________________________________

________________________________________________________Package Information

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

______________________________________________________________________________________ 11

NOTES

MAX1665S/V/X

Lithium-Ion Battery Pack Protector

Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.

12 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600

© 2000 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products.

NOTES