MAX1737EEI ,Stand-Alone Switch-Mode Lithium-Ion Battery-Charger ControllerApplicationsINPUT SUPPLYNotebook Computers Li+ Battery PacksCSSPDCINHand-Held Instruments Desktop C ..
MAX1737EEI ,Stand-Alone Switch-Mode Lithium-Ion Battery-Charger ControllerFeaturesThe MAX1737 is a switch-mode lithium-ion (Li+) battery Stand-Alone Charger for Up to Four ..
MAX1737EEI+ ,Stand-Alone Switch-Mode Lithium-Ion Battery-Charger ControllerFeaturesThe MAX1737 is a switch-mode lithium-ion (Li+) battery♦ Stand-Alone Charger for Up to Four ..
MAX1737EEI+ ,Stand-Alone Switch-Mode Lithium-Ion Battery-Charger ControllerEVALUATION KIT AVAILABLEMAX1737 Stand-Alone Switch-ModeLithium-Ion Battery-Charger Controller
MAX1737EEI+T ,Stand-Alone Switch-Mode Lithium-Ion Battery-Charger ControllerFeaturesThe MAX1737 is a switch-mode lithium-ion (Li+) battery♦ Stand-Alone Charger for Up to Four ..
MAX1739EEP ,Wide Brightness Range CCFL Backlight ControllersFeaturesThe MAX1739/MAX1839 fully integrated controllers are Fast Response to Input Changeoptimize ..
MAX4566CSE ,Quad/Dual / Low-Voltage / Bidirectional RF/Video SwitchesMAX4565/MAX4566/MAX456719-1252; Rev 0; 7/97Quad/Dual, Low-Voltage,Bidirectional RF/Video Switches__ ..
MAX4566CSE+ ,Quad Dual, Low-Voltage, Bidirectional RF Video SwitchesGeneral Description ________
MAX4567CSE ,Quad/Dual / Low-Voltage / Bidirectional RF/Video SwitchesFeaturesThe MAX4565/MAX4566/MAX4567 are low-voltage ' High 50Ω Off Isolation: -83dB at 10MHzT-switc ..
MAX4567EEE+ ,Quad Dual, Low-Voltage, Bidirectional RF Video SwitchesFeaturesThe MAX4565/MAX4566/MAX4567 are low-voltage ♦ High 50Ω Off Isolation: -83dB at 10MHzT-switc ..
MAX4567ESE+T ,Quad Dual, Low-Voltage, Bidirectional RF Video SwitchesMAX4565/MAX4566/MAX456719-1252; Rev 0; 7/97Quad/Dual, Low -Voltage,Bidirectional RF/Video Sw itches ..
MAX4568EUK+T ,±15kV ESD-Protected, Low-Voltage, SPDT/SPST, CMOS Analog SwitchesFeaturesThe MAX4561/MAX4568/MAX4569 are low-voltage,♦ ESD-Protected NO, NCESD-protected analog swit ..
MAX1737EEI
Stand-Alone Switch-Mode Lithium-Ion Battery-Charger Controller
General DescriptionThe MAX1737 is a switch-mode lithium-ion (Li+) battery
charger that charges one to four cells. It provides a
regulated charging current and a regulated voltage
with only a ±0.8% total voltage error at the battery ter-
minals. The external N-channel switch and synchronous
rectifier provide high efficiency over a wide input volt-
age range. A built-in safety timer automatically termi-
nates charging once the adjustable time limit has been
reached.
The MAX1737 regulates the voltage set point and charg-
ing current using two loops that work together to transi-
tion smoothly between voltage and current regulation. An
additional control loop monitors the total current drawn
from the input source to prevent overload of the input
supply, allowing the use of a low-cost wall adapter.
The per-cell battery voltage regulation limit is set
between +4.0V and +4.4V and can be set from one to
four by pin strapping. Battery temperature is monitored
by an external thermistor to prevent charging if the bat-
tery temperature is outside the acceptable range.
The MAX1737 is available in a space-saving 28-pin
QSOP package. Use the evaluation kit (MAX1737EVKIT)
to help reduce design time.
Applications
FeaturesStand-Alone Charger for Up to Four Li+ Cells±0.8% Accurate Battery Regulation VoltageLow Dropout: 98% Duty CycleSafely Precharges Near-Dead CellsContinuous Voltage and Temperature Monitoring <1µA Shutdown Battery Current Input Voltage Up to +28VSafety Timer Prevents OverchargingInput Current LimitingSpace-Saving 28-Pin QSOP300kHz PWM Oscillator Reduces Noise90% Conversion Efficiency
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller19-1626; Rev 1; 7/00
Typical Operating Circuit
Pin Configuration
Ordering InformationNotebook Computers
Hand-Held Instruments
Li+ Battery Packs
Desktop Cradle Chargers
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller
ABSOLUTE MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS(Circuit of Figure 1, VDCIN= VCSSN= VCSSP= +18V, SHDN= VL, CELL = GND, VBATT= VCS= +4.2V, VVADJ= VREF / 2, ISETIN =
ISETOUT = REF, RTHM= 10kΩ, TA
= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +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.
CSSP, CSSN, DCIN to GND...................................-0.3V to +30V
BST, DHI to GND....................................................-0.3V to +36V
BST to LX..................................................................-0.3V to +6V
DHI to LX..........................................-0.3V to ((BST - LX) + 0.3V)
LX to GND...............................................-0.3V to (CSSN + 0.3V)
FULLCHG,FASTCHG, FAULTto GND..................-0.3V to +30V
VL, VLO, SHDN, CELL, TIMER1, TIMER2, CCI,
CCS, CCV, REF, ISETIN, ISETOUT, VADJ,
THM to GND........................................................-0.3V to +6V
DLO to GND...............................................-0.3V to (VLO + 0.3V)
BATT, CS to GND...................................................-0.3V to +20V
PGND to GND, CSSP to CSSN..............................-0.3V to +0.3V
VL to VLO..............................................................-0.3V to +0.3V
VL Source Current...............................................................50mA
Continuous Power Dissipation (TA= +70°C)
28-Pin QSOP (derate 10.8mW/°C above +70°C)........860mW
Operating Temperature Range...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller
ELECTRICAL CHARACTERISTICS (continued)(Circuit of Figure 1, VDCIN= VCSSN= VCSSP= +18V, SHDN= VL, CELL = GND, VBATT= VCS= +4.2V, VVADJ= VREF / 2, ISETIN =
ISETOUT = REF, RTHM= 10kΩ, TA
= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller
ELECTRICAL CHARACTERISTICS (continued)(Circuit of Figure 1, VDCIN= VCSSN= VCSSP= +18V, SHDN= VL, CELL = GND, VBATT= VCS= +4.2V, VVADJ= VREF / 2, ISETIN =
ISETOUT = REF, RTHM= 10kΩ, TA
= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller
ELECTRICAL CHARACTERISTICS(Circuit of Figure 1, VDCIN= VCSSN= VCSSP= +18V, SHDN= VL, CELL = GND, VBATT= VCS= +4.2V, VVADJ= VREF/2, ISETIN =
ISETOUT = REF, RTHM= 10kΩ, TA
= -40°C to +85°C, unless otherwise noted.) (Note 9)
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller
ELECTRICAL CHARACTERISTICS (continued)
(Circuit of Figure 1, VDCIN= VCSSN= VCSSP= +18V, SHDN= VL, CELL = GND, VBATT= VCS= +4.2V, VVADJ= VREF/2, ISETIN =
ISETOUT = REF, RTHM= 10kΩ, TA= -40°C to +85°C, unless otherwise noted.) (Note 9)
Note 1:Battery Regulation Voltage = Number of Cells ×(3.979V + 0.10526 ×VVADJ).
Note 2:This transconductance is for one cell. Divide by number of cells to determine actual transconductance.
Note 3:See Thermistorsection.
Note 4:Below this threshold, the charger reverts to prequalification mode and ICHGis reduced to about 5% of full scale.
Note 5:Above this threshold, the charger returns to reset.
Note 6:After full-charge state is complete and peak inductor current falls below this threshold, FULLCHGoutput switches high.
Battery charging continues until top-off timeout occurs.
Note 7:After charging is complete, when BATT voltage falls below this threshold, a new charging cycle is initiated.
Note 8:In shutdown, charging ceases and battery drain current drops to 5µA (max), but internal IC bias current remains on.
Note 9:Specifications to -40°C are guaranteed by design and not production tested.
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller
Typical Operating Characteristics
(Circuit of Figure 1, VDCIN= +18V, ISETIN = ISETOUT = REF, VVADJ= VREF / 2, TA= +25°C, unless otherwise noted.)
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller
Pin Description
MAX1737
Stand-Alone Switch-Mode
Lithium-Ion Battery-Charger Controller
Detailed Description
The MAX1737 includes all of the functions necessary to
charge between one and four series Li+ battery cells. It
includes a high-efficiency synchronous-rectified step-
down DC-DC converter that controls charging voltage
and current. It also includes input source-current limit-
ing, battery temperature monitoring, battery undervolt-
age precharging, battery fault indication, and a state
machine with timers for charge termination.
The DC-DC converter uses an external dual N-channel
MOSFET as a switch and a synchronous rectifier to
convert the input voltage to the charging current or volt-
age. The typical application circuit is shown in Figure 1.
Figure 2 shows a typical charging sequence and
Figure 3 shows the block diagram. Charging current is
set by the voltage at ISETOUT and the voltage across
R18. The battery voltage is measured at the BATT pin.
The battery regulation voltage is set to 4.2V per cell
and can be adjusted ±5% by changing the voltage at
the VADJ pin. By limiting the adjust range, the voltage
