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For small orders, phone 1-800-835-8769.
General Description
The MAX1666 provides complete protection against over-
voltage, undervoltage, overcharge current, overdischarge
current, and cell mismatch for 2-cell to 4-cell Lithium-Ion
battery packs. The voltage of each cell in the battery pack
is checked and compared to the programmable threshold
and to the other cells in the pack.
The MAX1666 protects the battery pack in an overcurrent
condition by disconnecting the pack from the load at a pro-
grammable limit. On-chip power MOSFET drivers control
external P-channel MOSFETs to disconnect the cells from
external terminals when faults occur.
The MAX1666 employs a unique timing scheme that allows
three modes of operation, for optimal performance and bat-
tery power conservation. The MAX1666 can operate in a
stand-alone configuration or in conjunction with a micro-
controller. It is available in three versions: the "S" version
monitors two Li-Ion cells, the "V" version monitors three
cells, and the "X" version monitors four cells.
Applications
2/3/4-Cell Lithium-Ion Battery Pack
Features
o
Overvoltage Protection
Programmable Limits from +4.0V to +4.4V
Accurate to ±0.5%
o
Undervoltage Protection
Programmable Limits from +2.0V to +3.0V
Accurate to ±2.5%
o
Cell Mismatch Protection
Programmable Limits from 0 to 500mV
Accurate to ±10%
o
Overcharge Current Protection
o
Overdischarge Current Protection
o
Low Operating Supply Current: 30µA typ
o
Low Standby Current: 1µA max
o
+28V max Input Voltage
o
Available in Small 16-Pin QSOP (MAX1666S) and
20-Pin QSOP (MAX1666V/X) Packages
MAX1666S/V/X
Advanced Lithium-Ion
Battery-Pack Protector
________________________________________________________________
Maxim Integrated Products
1
TOP VIEW
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
UVO
V
CC
REF
OVA
CGO
TKO
DSO
SRC
UVA
MMA
WRN
PKF
B1P
B2P
B3P
B3P
12
11
9
10
CGI
DSI
PKN
GND
MAX1666V
20
19
18
17
16
15
14
13
1
2
3
4
5
6
7
8
UVO
V
CC
REF
OVA
CGO
TKO
DSO
SRC
UVA
MMA
WRN
PKF
B1P
B2P
B3P
B4P
12
11
9
10
CGI
DSI
PKN
GND
MAX1666X
16
15
14
13
12
11
10
9
1
2
3
4
5
6
7
8
SRC
V
CC
REF
OVA
UVA
MMA
PKF
CGI
DSI
MAX1666S
DSO
TKO
BIP
CGO
B2P
GND
PKN
QSOP
QSOP
QSOP
19-1465; Rev 1; 7/99
PART
MAX1666SEEE
MAX1666VEEP
MAX1666XEEP
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
TEMP. RANGE
PIN-PACKAGE
16 QSOP
20 QSOP
20 QSOP
Pin Configurations
Ordering Information
Selector Guide
Typical Operating Circuits appear at end of data sheet.
NUMBER OF LI-ION CELLS
PART
MAX1666S
2
3
4
MAX1666X
MAX1666V
MAX1666S/V/X
Advanced Lithium-Ion
Battery-Pack Protector
2
_______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
(V
SRC
= 16V, each cell voltage V
CELL
= 3.6V, 330k
load at REF, T
A
= 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.
SRC, DSO, TKO, CGO, UVO, PKF, WRN to GND ...-0.3V to +28V
V
CC
, REF, OVA, UVA, MMA to GND ........................-0.3V to +6V
B4P to B3P ...............................................................-0.3V to +6V
B3P to B2P ...............................................................-0.3V to +6V
B2P to B1P ...............................................................-0.3V to +6V
B1P to GND ..............................................................-0.3V to +6V
PKN to GND...........................................................................±2V
V
CC
, CGI, DSI to PKN...............................................-0.3V to +6V
Continuous Power Dissipation (T
A
= +70°C)
16-Pin QSOP (derate 8.3mW/°C above +70°C)...........667mW
20-Pin QSOP (derate 9.1mW/°C above +70°C)...........727mW
Operating Temperature Range ...........................-40°C to +85°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10sec) .............................+300°C
No faults, long time average current from
the top battery terminal B_P
V
SRC
- V
B_P
= 1V
V
SRC
- V
B_P
R
LOAD
665
, 2V < V
CELL
< 4.4V
Pulse on
CONDITIONS
µA
30
45
I
SUP
Supply Current
µA
2
10
V
1
Charge Mode Detection Threshold
SRC Input Current Range
µA
1
I
SHDN
Shutdown Supply Current
V
3.09
3.25
3.41
V
CC
V
CC
Output Voltage
V
2.7
2.85
3
V
CC
Undervoltage Lockout
Threshold
V
1.221
V
REF
Reference Output Voltage
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
Cell voltage rising
Cell voltage falling
4.378
4.400
4.422
V
4.2
3.980
4.000
4.020
Overvoltage Threshold
mV
200
Overvoltage Threshold Hysteresis
V
1.950
2.000
2.050
Undervoltage Threshold
2.500
2.925
3.000
3.075
OVA, UVA, MMA = REF
Above undervoltage threshold,
cell voltage falling
mV
All cells > 2V
-220
-200
-180
PKN to GND Overcharge Current
Threshold
nA
0.1
20
OVA, UVA, MMA Input Current
mV
100
mV
100
Undervoltage Threshold Hysteresis
WRN Early Warning Threshold
mV
±0
Cell Mismatch Threshold
±250
±450
±500
±550
mV
270
300
330
PKN to GND Overdischarge
Current Threshold
OVA = GND
V
OVA
= V
REF
/ 2
OVA = REF
UVA = GND
V
UVA
= V
REF
/ 2
UVA = REF
MMA = GND
V
MMA
= V
REF
/ 2
MMA = REF
mV
200
WRN Early Warning Threshold
Hysteresis
MAX1666S/V/X
Advanced Lithium-Ion
Battery-Pack Protector
_______________________________________________________________________________________
3
No faults, long time average current from the
top battery terminal B_P
V
SRC
- V
B_P
= 1V to 4V
V
SRC
- V
B_P
4.373
4.427
R
LOAD
665
, 2V < V
CELL
< 4.4V
3.975
4.025
CONDITIONS
Overvoltage Threshold
OVA, UVA, MMA = REF
µA
45
I
SUP
Supply Current
µA
10
V
1
Charge Mode Detection
Threshold
SRC Input Current Range
nA
20
OVA, UVA, MMA Leakage
µA
1
I
SHDN
Shutdown Supply Current
V
3.09
3.41
V
CC
V
CC
Output Voltage
V
2.7
3
V
CC
Undervoltage Lockout
Threshold
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
OVA = GND
OVA = REF
V
V
2.925
3.075
1.950
2.050
Undervoltage Threshold
UVA = GND
UVA = REF
CONDITIONS
No faults, V
DSO
= V
CGO
= V
UVO
= 1V to 27V
V
DSO
= V
SRC
- 4V and V
CGO
= V
SRC
- 4V,
fault condition
V
DSO
= V
CGO
= V
UVO
= 27V, fault condition
ms
1.6
2.4
3.2
t
I-DELAY
Overdischarge/Overcharge
Current Fault Blanking Time
ms
330
550
770
t
P-DELAY
Overcurrent Fault Timer Delay
µA
20
30
40
DSO, CGO, UVO Output Sink
Current
mA
2
10
DSO, CGO Output Source
Current
µA
0.2
DSO, CGO, UVO Leakage
Current
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
V
DSI
, V
CGI
= 5V
Referenced to PKN
Referenced to PKN
Fault condition, V
WRN
= 0.4V
Fault condition, V
PKF
= 0.4V
V
PKF
= V
WRN
= 27V
µA
1
DSI, CGI Input Current
V
0.45
V
2
TKO = GND
DSI, CGI Input High Voltage
DSI, CGI Input Low Voltage
mA
2
4
WRN Sink Current
mA
4
8
PKF Sink Current
µA
0.2
PKF, WRN Leakage Current
k
100
200
TKO Pull-Down Resistance
mA
1
8
TKO Source Current
Fault persistent for 4 consecutive sample
periods
ms
180
320
460
t
F-DELAY
Undervoltage, Overvoltage, or
Mismatch Fault, to DSO, CGO,
TKO Transition Delay
ELECTRICAL CHARACTERISTICS (continued)
(V
SRC
= 16V, each cell voltage V
CELL
= 3.6V, 330k
load at REF, T
A
= 0°C to +85°C, unless otherwise noted. Typical values are at
T
A
= +25°C.)
ELECTRICAL CHARACTERISTICS
(V
SRC
= 16V, each cell voltage V
CELL
= 3.6V, 330k
load at REF, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 1)
MAX1666S/V/X
Advanced Lithium-Ion
Battery-Pack Protector
4
_______________________________________________________________________________________
CONDITIONS
No faults; V
DSO
, V
CGO
, V
UVO
= 1V to 27V
V
DSO
= V
SRC
- 4V and V
CGO
= V
SRC
- 4V,
fault condition
V
DSO
= V
CGO
= V
UVO
= 27V, fault condition
ms
1.6
3.2
t
I-DELAY
Overdischarge/Overcharge
Current Fault Blanking Time
ms
330
770
t
P-DELAY
mV
All cells > 2V, MMA = REF
-220
-180
PKN to GND Overcharge
Current Threshold
Overcurrent Fault Timer Delay
µA
20
40
DSO, CGO UVO Output Sink
Current
mA
2
DSO, CGO Output Source
Current
µA
0.2
DSO, CGO, UVO Leakage
Current
UNITS
MIN
TYP
MAX
SYMBOL
PARAMETER
mV
±450
±550
Cell Mismatch Threshold
mV
270
330
PKN to GND Overdischarge
Current Threshold
V
DSI
= V
CGI
= 5V
Referenced to PKN
Referenced to PKN
Fault condition, V
WRN
= 0.4V
Fault condition, V
PKF
= 0.4V
V
PKF
= V
WRN
= 27V
µA
1
DSI, CGI Input Current
V
0.45
V
2
TKO = GND
DSI, CGI Input High Voltage
DSI, CGI Input Low Voltage
mA
2
WRN Sink Current
mA
4
PKF Sink Current
µA
0.2
PKF, WRN Leakage Current
k
100
TKO Pull-Down Resistance
mA
1
TKO Source Current
Fault persistent for 4 consecutive sample
periods
ms
180
460
t
F-DELAY
Undervoltage, Overvoltage, or
Mismatch Fault, to DSO, CGO,
TKO Transition Delay
Note 1:
Specifications to -40°C are guaranteed by design, not production tested.
ELECTRICAL CHARACTERISTICS
(V
SRC
= 16V, each cell voltage V
CELL
= 3.6V, 330k
load at REF, T
A
= -40°C to +85°C, unless otherwise noted.) (Note 1)
MAX1666S/V/X
Advanced Lithium-Ion
Battery-Pack Protector
_______________________________________________________________________________________
5
700
720
710
740
730
760
750
770
-40
0
20
-20
40
60
80
100
SHUTDOWN SUPPLY CURRENT
vs. TEMPERATURE
MAX1666toc01
TEMPERATURE (°C)
SUPPLY CURRENT (nA)
V
CELL
= 3.6V
25
27
31
29
33
35
-40
0
20
-20
40
60
80
100
SUPPLY CURRENT
vs. TEMPERATURE
MAX1666toc02
TEMPERATURE (°C)
SUPPLY CURRENT (
µ
A)
V
CELL
= 3.6V
3.0000
3.0005
3.0010
3.0015
UNDERVOLTAGE THRESHOLD
vs. TEMPERATURE
MAX1666toc03
TEMPERATURE (°C)
UNDERVOLTAGE THRESHOLD (V)
-40
20
40
-20
0
60
80
100
UVA = REF
4.385
4.390
4.395
4.400
OVERVOLTAGE THRESHOLD
vs. TEMPERATURE
MAX1666toc04
TEMPERATURE (°C)
UNDERVOLTAGE THRESHOLD (V)
-40
20
40
-20
0
60
80
100
OVA = REF
295
297
296
299
298
301
300
302
-40
0
20
-20
40
60
80
100
OVERDISCHARGE THRESHOLD
vs. TEMPERATURE
MAX1666toc07
TEMPERATURE (°C)
OVERDISCHARGE THRESHOLD (mV)
495
497
496
499
498
500
501
-40
20
40
-20
0
60
80
100
MISMATCH VOLTAGE THRESHOLD
vs. TEMPERATURE
MAX1666toc05
TEMPERATURE (°C)
MISMATCH VOLTAGE THRESHOLD (mV)
MMA = REF
199
200
201
202
203
OVERCHARGE THRESHOLD
vs. TEMPERATURE
MAX1666toc06
TEMPERATURE (°C)
OVERCHARGE THRESHOLD (mV)
-40
20
40
-20
0
60
80
100
1ms/div
OVERDISCHARGE PROTECTION
PKN
(0.5V/div)
DSO
(10V/div)
MAX1666toc08
t
I-DELAY
100ms/div
OVERDISCHARGE RECOVERY TIME
(0.5V/div)
(10V/div)
PKN
DSO
MAX1666toc09
t
P
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
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