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Maxim Integrated |
19-1605; Rev 0; 1/00
Lithium-Ion Battery Pack Protector
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 fea-
ture prevents excessive pack current.
Applications
Lithium-Ion Battery Packs
____________________________Features
o Complete Protection Against:
Cell Overvoltage
Cell Undervoltage
o Pack Protection for Excessive Charge and
Discharge
o Very Low Supply Current: 16µA typ
o Low Standby Current: 1µA max
o Matched Cell Input Bias Current (<500pA)
Preserves Cell Balance
PART
MAX1665SESA
MAX1665VESA
MAX1665XESA
Ordering Information
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
8 SO
8 SO
8 SO
CELL
COUNT
2
3
4
Typical Operating Circuit
(+)
B4P B3P
DSG B2P
MAX1665X
CHG B1P
BN
(-) PKN
TOP VIEW
Pin Configuration
I.C. (B4P) 1
DSG 2
CHG 3
PKN 4
MAX1665S
MAX1665V
MAX1665X
8 I.C. [B3P]
7 B2P
6 B1P
5 BN
SO
NOTES: I.C. = INTERNAL CONNECTION. MAKE NO CONNECTIONS TO THIS PIN.
( ) ARE FOR THE MAX1665X.
[ ] ARE FOR THE MAX1665V AND MAX1665X.
________________________________________________________________ Maxim Integrated Products 1
For free samples and the latest literature visit www.maxim-ic.com or phone 1-800-998-8800.
For small orders, phone 1-800-835-8769.
Lithium-Ion Battery Pack Protector
ABSOLUTE MAXIMUM RATINGS
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 (VB2P + 0.3V)
MAX1665V............................................-0.3V to (VB3P + 0.3V)
MAX1665X............................................-0.3V to (VB4P + 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 (TA= +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
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.
ELECTRICAL CHARACTERISTICS
(VB2P = 8V (MAX1665S), VB3P = 12V (MAX1665V), VB4P = 16V (MAX1665X), TA = 0°C to +85°C, unless otherwise noted. Typical
values are at TA = +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX UNITS
B2P Voltage Range
VB2P MAX1665S
4 10 V
B3P Voltage Range
VB3P MAX1665V
4 15 V
B4P Voltage Range
VB4P MAX1665X
4 20 V
Overvoltage Threshold
VOV Cell voltage rising
4.26 4.3 4.34
V
Overvoltage Hysteresis
VCE
0.10 V
Undervoltage Threshold
VUV
2.4 2.5 2.6
V
Undervoltage RESET
VRE VBN - VPKN
0 18 30 mV
Overcurrent Sense Threshold
VCH
±200 ±250 ±300 mV
Overcurrent Hysteresis
VCH2
5 mV
Overvoltage/Undervoltage
Delay
tUV (Note 1)
200 ms
Overcurrent Detection Delay
tIO
CHG, DSG Output Voltage High
IOUT = 100µA
MAX1665S
MAX1665V
MAX1665X
10
VB2P - 1.8
VB2P - 0.54
VB3P - 1.8
VB3P - 0.54
VB4P - 1.8
VB4P - 0.54
ms
V
DSG Output Voltage High
(Note 2)
MAX1665X, IOUT = 100µA, VB4P = 24V,
VBN = 100mV
17 20
V
CHG Output Voltage Low
DSG Output Voltage Low
VCHGL
VDSGL
ICHG = -100µA
IDSG = -1µA
VPKN + 0.1
VBN + 0.1
V
V
CHG, DSG Output Source
Current
IOH CHG = PKN, DSG = BN
10 25
mA
CHG Output Sink Current
DSG Output Sink Current
Overcurrent Sampling - tON
Overcurrent Sampling - tOFF
Input Bias Current (Note 3)
IOL
IOL
tON
tOFF
IBIAS
VCHG = VPKN + 3.0V
VDSG = VBN + 3.0V
VPKN = ±300mV
VPKN = ±300mV
MAX1665SESA, VB1P = 4V
MAX1665VESA, VB1P = 4V, VB2P = 8V
MAX1665XESA, VB1P = 4V, VB2P = 8V,
VB3P = 12V
0.5 2
mA
0.5 2
µA
8.2 ms
135 ms
3 10 nA
3 10
nA
3 10
2 _______________________________________________________________________________________
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