MAX1909ETI+-MAX1909ETI+T-MAX8725ETI+-MAX8725ETI+T Fast Delivery |IC PHOENIX CO.,LIMITED

MAX8725ETI+ ,Multichemistry Battery Chargers with Automatic System Power SelectorApplicationsNotebook and Subnotebook Computers Minimum Operating CircuitHand-Held Data TerminalsP3T ..
MAX8725ETI+ ,Multichemistry Battery Chargers with Automatic System Power SelectorElectrical Characteristics(Circuit of Figure 1, V = V = V = 18V, V = V = V = 12V, V = V = 1.8V, MOD ..
MAX8725ETI+T ,Multichemistry Battery Chargers with Automatic System Power SelectorFeatures• Precise Measurement Improves Safety andThe MAX1909/MAX8725 highly integrated control ICsP ..
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MAX8727ETB+ ,TFT-LCD Step-Up DC-DC ConverterApplicationsPART TEMP RANGE PIN-PACKAGEMAX8727ETB -40°C to +85°C 10 Thin DFN 3mm x 3mmNotebook Comp ..
MAX8727ETB+T ,TFT-LCD Step-Up DC-DC ConverterFeaturesThe MAX8727 is a high-performance step-up DC-DC♦ 90% Efficiencyconverter that provides a re ..
MB84VD21183EM-70PBS , Stacked MCP (Multi-Chip Package) FLASH MEMORY & SRAM CMOS
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MB84VD22181FM-70PBS , 32M (X16) FLASH MEMORY & 4M (X16) STATIC RAM
MB84VD22182EE-90 ,32M (x 8/x16) FLASH MEMORY & 4M (x 8/x16) STATIC RAMFUJITSU SEMICONDUCTORDS05-50204-2EDATA SHEETStacked MCP (Multi-Chip Package) FLASH MEMORY & SRAMCMO ..
MB84VD22183EE-90 ,32M (x 8/x16) FLASH MEMORY & 4M (x 8/x16) STATIC RAMFEATURES• Power supply voltage of 2.7 to 3.3 V• High performance90 ns maximum access time (Flash)85 ..
MB84VD22184FM-70 , 32M (X16) FLASH MEMORY & 4M (X16) STATIC RAM

MAX1909ETI+-MAX1909ETI+T-MAX8725ETI+-MAX8725ETI+T
Multichemistry Battery Chargers with Automatic System Power Selector
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
EVALUATION KIT AVAILABLE
General Description
The MAX1909/MAX8725 highly integrated control ICs
simplify construction of accurate and efficient multi-
chemistry battery chargers. The MAX1909/MAX8725
use analog inputs to control charge current and volt-
age, and can be programmed by a host microcontroller
(µC) or hardwired. High efficiency is achieved through
use of buck topology with synchronous rectification.
The maximum current drawn from the AC adapter is pro-
grammable to avoid overloading the AC adapter when
supplying the load and the battery charger simultane-
ously. The MAX1909/MAX8725 provide a digital output
that indicates the presence of an AC adapter, and an
analog output that monitors the current drawn from the
AC adapter. Based on the presence or absence of the
AC adapter, the MAX1909/MAX8725 automatically
select the appropriate source for supplying power to the
system by controlling two external p-channel MOSFETs.
Under system control, the MAX1909/MAX8725 allow the
battery to undergo a relearning or conditioning cycle in
which the battery is completely discharged through the
system load and then recharged.
The MAX1909 includes a conditioning charge feature
while the MAX8725 does not. The MAX1909/MAX8725
are available in space-saving 28-pin, 5mm ✕5mm thin
QFN packages and operate over the extended -40°C to
+85°C temperature range. The MAX1909/MAX8725 are
now available in lead-free packages.
Applications
Notebook and Subnotebook Computers
Hand-Held Data Terminals
Benefits and FeaturesPrecise Measurement Improves Safety and
Performance±0.5% Accurate Charge Voltage (0°C to +85°C)±3% Accurate Input Current Limiting±5% Accurate Charge CurrentAnalog Inputs Control Charge Current and Charge
VoltageCharge Any Battery Chemistry: Li+, NiCd, NiMH,
Lead Acid, etc.Up to 17.65V (max) Battery VoltageMaximum 28V Input VoltageProgrammable Charge Current > 4AIntelligent AC Adapter Interface Makes Design EasierAutomatic System Power/Source SelectionAnalog Monitoring of Current Drawn from AC Input
SourceDigital Output Indicates AC Adapter PresenceGreater than 95% Efficiency Extends Battery Life
Ordering Information
PARTTEMP RANGEPIN-PACKAGE
MAX1909ETI-40°C to +85°C28 Thin QFN
MAX1909ETI+-40°C to +85°C28 Thin QFN
MAX8725ETI-40°C to +85°C28 Thin QFN
MAX8725ETI+-40°C to +85°C28 Thin QFN27262524232291011121314
MAX1909
MAX8725
THIN QFN
TOP VIEW
LDO
DCIN
ACIN
REF
GND/PKPRES
ACOK
MODE
PDLPDSCSSPCSSNSRCDHIDHIV
DLOV
DLO
PGND
CSIP
CSIN
BATT
GND
CCSCCV
CCI
VCTL
ICTL
CLSIINP
Pin Configuration
CSSPCSSN
LDO
DHI
DLOV
DLO
PGND
CSIP
CSIN
BATT
GND
DCIN
VCTL
ICTL
MODE
ACIN
ACOK
CLS
CCV
CCI
CCS
REF
LDO
AC ADAPTER: INPUT
0.01Ω
10µHN1
0.015Ω
EXTERNAL LOAD
LDO
PDS
PDLSRC
LDO
REF
IINPIINP
DHIV
SRC
MAX1909
MAX8725
PKPRESMAX8725 ONLY
Minimum Operating Circuit
+Denotes a lead(Pb)-free/RoHS-compliant package.
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Absolute Maximum Ratings
Electrical Characteristics
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, 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.
DCIN, CSSP, CSSN, SRC, ACOK to GND..............-0.3V to +30V
DHIV........................................................…SRC + 0.3, SRC - 6V
DHI, PDL, PDS to GND...............................-0.3V to (VSRC+ 0.3)
BATT, CSIP, CSIN to GND.....................................-0.3V to +20V
CSIP to CSIN or CSSP to CSSN or PGND to GND...-0.3V to +0.3V
CCI, CCS, CCV, DLO, IINP, REF,
ACIN to GND........................................-0.3V to (VLDO+ 0.3V)
DLOV, VCTL, ICTL, MODE, CLS, LDO,
PKPRESto GND...................................................-0.3V to +6V
DLOV to LDO.........................................................-0.3V to +0.3V
DLO to PGND..........................................-0.3V to (DLOV + 0.3V)
LDO Short-Circuit Current...................................................50mA
Continuous Power Dissipation (TA= +70°C)
28-Pin TQFN (derate 20.8mW/°C above +70°C).......1666mW
Operating Temperature Range...........................-40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range.............................-60°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITS
CHARGE VOLTAGE REGULATIONVCTL Range 0 3.6 V
VVCTL = 3.6V (3 or 4 cells);
not including VCTL resistor tolerances -0.8 +0.8
VVCTL = 3.6V/20 (3 or 4 cells); not including
VCTL resistor tolerances -0.8 +0.8
VVCTL = 3.6V (3 or 4 cells); including VCTL
resistor tolerances of 1% -1.0 +1.0
Battery Regulation Voltage
Accuracy
VVCTL = VLDO (3 or 4 cells, default
threshold of 4.2V/cell) -0.5 +0.5%VVCTL Default Threshold VVCTL rising 4.1 4.3 VVVCTL = 3V 0 2.5VCTL Input Bias Current VDCIN = 0, VVCTL = 5V 0 12 µA
CHARGE-CURRENT REGULATIONMAX1909 0 3.6 ICTL Range MAX8725 0 3.2 VCSIP-to-CSIN Full-Scale Current-
Sense Voltage 69.37 75.00 80.63 mVMAX1909: VICTL = 3.6V (not including ICTL
resistor tolerances) -7.5 +7.5MAX8725: VICTL = 3.2V (not including ICTL
resistor tolerances) -5 +5MAX1909: VICTL = 3.6V x 0.5, MAX8725:
VICTL = 3.2V x 0.5 (not including ICTL
resistor tolerances) -5 +5MAX1909: VICTL = 0.9V (not including ICTL
resistor tolerances) -7.5 +7.5
Charge-Current AccuracyMAX8725: VICTL = 0.18V (not including
ICTL resistor tolerances) -30 +30%
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Electrical Characteristics (continued)
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITSMAX1909: VICTL = 3.6V x 0.5, MAX8725:
VICTL = 3.2V x 0.5 (including ICTL resistor
tolerances of 1%) -7.0 +7.0Charge-Current AccuracyVICTL = VLDO (default threshold of 45mV) -5 +5%VICTL Default Threshold VICTL rising 4.1 4.2 4.3 VBATT/CSIP/CSIN Input Voltage
Range 0 19 VCharging enabled 350 650 CSIP/CSIN Input Current Charging disabled; VDCIN = 0 or VICTL = 0 0.1 1 µAMAX1909 0.75 ICTL Power-Down Mode
Threshold Voltage MAX8725 0.06 VMAX1909 0.85 ICTL Power-Up Mode Threshold
Voltage MAX8725 0.11 VVICTL = 3V -1 +1ICTL Input Bias Current VDCIN = 0V, VICTL = 5V -1 +1 µAINPUT CURRENT REGULATIONCSSP-to-CSSN Full-Scale
Current-Sense Voltage 72.75 75.00 77.25 mVVCLS = REF -3 +3VCLS = REF x 0.75 -3 +3Input Current-Limit
Accuracy VCLS = REF x 0.5 -4 +4%C S S P /C S S N Inp ut V ol tag e Rang e 8.0 28 VVCSSP = VCSSN = VDCIN > 8.0V 450 730CSSP/CSSN Input Current VDCIN = 0 0.1 1 µACLS Input Range 1.6 REF VCLS Input Bias Current VCLS = 2.0V -1 +1 µAIINP Transconductance VCSSP - VCSSN = 56mV 2.7 3.0 3.3 mA/VVCSSP - VCSSN = 75mV, terminated with
10kΩ -7.5 +7.5VCSSP - VCSSN = 56mV, terminated with
10kΩ -5 +5IINP AccuracyVCSSP - VCSSN = 20mV, terminated with
10kΩ -10 +10%IINP Output Current VCSSP - VCSSN = 150mV, VIINP = 0V 350 µAIINP Output Voltage VCSSP - VCSSN = 150mV, VIINP = float 3.5 V
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Electrical Characteristics (continued)
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITS
SUPPLY AND LINEAR REGULATORDCIN Input Voltage Range VDCIN 8.0 28 VDCIN falling 7 7.4 DCIN Undervoltage-Lockout Trip
Point DCIN rising 7.5 7.85 VDCIN Quiescent Current IDCIN 8.0V < VDCIN < 28V 2.7 6 mAVBATT = 19V, VDCIN = 0V, or ICTL = 0V 0.1 1VBATT = 16.8V, VDCIN = 19V, ICTL = 0V 0.1 1 BATT Input Current IBATTVBATT = 2V to 19V, VDCIN > VBATT + 0.3V 200 500µALDO Output Voltage 8.0V < VDCIN < 28V, no load 5.25 5.4 5.55 VLDO Load Regulation 0 < ILDO < 10mA 80 115 mVLDO Undervoltage-Lockout Trip
Point VDCIN = 8.0V 3.20 4 5.15 V
REFERENCEREF Output Voltage Ref 0 < IREF < 500µA 4.2023 4.2235 4.2447 VREF Undervoltage-Lockout Trip
Point REF falling 3.1 3.9 V
TRIP POINTSBATT POWER_FAIL Threshold VDCIN - VBATT, VDCIN falling 50 100 150 mVBATT POWER_FAIL Threshold
Hysteresis 100 200 300 mVACIN Threshold ACIN rising 2.007 2.048 2.089 VACIN Threshold Hysteresis 10 20 30 mVACIN Input Bias Current VACIN = 2.048V -1 +1 µA
SWITCHING REGULATOR
DHI Off-Time V B AT T = 16.0V , V D C I N = 19V , V M OD E = 3.6V 360 400 440 ns
DHI Minimum Off-Time V B AT T = 16.0V , V D C I N = 17V , V M OD E = 3.6V 260 300 350 nsDLOV Supply Current IDLOV DLO low 5 10 µASense Voltage for Minimum
Discontinuous Mode Ripple
Current 7.5 mVCycle-by-Cycle Current-Limit
Sense Voltage 97 mVSense Voltage for Battery
Undervoltage Charge Current MAX1909 only, BATT = 3.0V per cell 3 4.5 6 mVMAX1909 only, MODE = float (3 cell),
VBATT rising 9.18 9.42
Battery Undervoltage Threshold MAX1909 only, MODE = LDO (4 cell),
VBATT rising 12.235 12.565VDHIV Output Voltage With respect to SRC -4.5 -5.0 -5.5 V
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Electrical Characteristics (continued)
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITSDHIV Sink Current 10 mADHI On-Resistance Low DHI = VDHIV, IDHI = -10mA 2 5 ΩDHI On-Resistance High DHI = VCSSN, IDHI = 10mA 2 4 ΩDLO On-Resistance High VDLOV = 4.5V, IDLO = +100mA 3 7 ΩDLO On-Resistance Low VDLOV = 4.5V, IDLO = -100mA 1 3 Ω
ERROR AMPLIFIERSV C TL = 3.6, V BATT = 16.8V , M OD E = LD O 0.0625 0.125 0.2500 GMV Loop Transconductance V C TL = 3.6, V BATT = 12.6V , M OD E = FLOAT 0.0833 0.167 0.3330 mA/VGMI Loop Transconductance MAX1909: ICTL = 3.6V, MAX8725: VICTL =
3.2V, VCSSP - VCSIN = 75mV 0.5 1 2 mA/VGMS Loop Transconductance VCLS = 2.048V, VCSSP - VCSSN = 75mV 0.5 1 2 mA/VCCI/CCS/CCV Clamp Voltage 0.25V < VCCV < 2.0V, 0.25V < VCCI < 2.0V,
0.25V < VCCS < 2.0V 150 300 600 mV
LOGIC LEVELSMODE Input Low Voltage 0.8 VMODE Input Middle Voltage 1.6 1.8 2.0 VMODE Input High Voltage 2.8 VMODE Input Bias Current MODE = 0V or 3.6V -2 +2 µA
ACOK AND PKPRESACOK Input Voltage Range 0 28 VACOK Sink Current VACOK = 0.4V, ACIN = 1.5V 1 mAACOK Leakage Current VACOK = 28V, ACIN = 2.5V 1 µAPKPRES Input Voltage
Range 0 LDO VPKPRES Input Bias Current -1 +1 µAPKPRES Battery Removal Detect
Threshold MAX8725, PKPRES rising 55 % of
LDOPKPRES Hysteresis MAX8725 1 %
PDS, PDL SWITCH CONTROLPDS Switch Turn-Off Threshold VDCIN - VBATT, VDCIN falling 50 100 150 mVPDS Switch Threshold Hysteresis VDCIN - VBATT 100 200 300 mVPDS Output Low Voltage, PDS
Below SRC IPDS = 0A 8 10 12 VPDS Turn-On Current PDS = SRC 6 12 mAPDS Turn-Off Current VPDS = VSRC - 2V, VDCIN = 16V 10 50 mAPDL Switch Turn-On Threshold VDCIN - VBATT, VDCIN falling 50 100 150 mVPDL Switch Threshold Hysteresis VDCIN - VBATT 100 200 300 mV
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Electrical Characteristics
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, TA= -40°C to +85°C, unless otherwise noted.)
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITS
CHARGE VOLTAGE REGULATIONVCTL Range 0 3.6 V
VVCTL = 3.6V (3 or 4 cells); not including
VCTL resistor tolerances -0.8 +0.8
VVCTL = 3.6V/20 (3 or 4 cells); not including
VCTL resistor tolerances -0.8 +0.8
VVCTL = 3.6V (3 or 4 cells); including VCTL
resistor tolerances of 1% -1.0 +1.0
Battery Regulation Voltage
Accuracy
VVCTL = VLDO (3 or 4 cells, default
threshold of 4.2V/cell) -0.8 +0.8%VVCTL Default Threshold VVCTL rising 4.1 4.3 VVVCTL = 3V 0 2.5VCTL Input Bias Current VDCIN = 0V, VVCTL = 5V 0 12 µA
CHARGE-CURRENT REGULATIONMAX1909 0 3.6 ICTL Range MAX8725 0 3.2 VCSIP-to-CSIN Full-Scale Current-
Sense Voltage 69.37 80.63 mVMAX1909: VICTL = 3.6V (not including ICTL
resistor tolerances) -7.5 +7.5MAX8725: VICTL = 3.2V (not including ICTL
resistor tolerances) -5 +5MAX1909: VICTL = 3.6V x 0.5, MAX8725:
VICTL = 3.2V x 0.5 (not including ICTL
resistor tolerances) -5 +5MAX1909: VICTL = 0.9V (not including ICTL
resistor tolerances) -7.5 +7.5
Charge-Current AccuracyMAX8725: VICTL = 0.18V (not including -30 +30%
Electrical Characteristics (continued)
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, TA= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITSPDL Turn-On Resistance PDL = GND 50 100 150 kΩPDL Turn-Off Current VSRC - VPDL = 1.5V 6 12 mASRC = 19V, DCIN = 0V 1 SRC Input Bias Current SRC = 19, VBATT = 16V 450 1000 µADelay Time Between PDL and
PDS Transitions 2.5 5 7.5 µs
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Electrical Characteristics (continued)
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, TA= -40°C to +85°C, unless otherwise noted.)
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITSMAX1909: VICTL = 3.6V x 0.5, MAX8725:
VICTL = 3.2V x 0.5 (including ICTL resistor
tolerances of 1%) -7.0 +7.0Charge-Current AccuracyVICTL = VLDO (default threshold of 45mV) -5 +5%VICTL Default Threshold VICTL rising 4.3 VBATT/CSIP/CSIN Input Voltage
Range 0 19 VCSIP/CSIN Input Current Charging enabled 650 µAMAX1909 0.75 ICTL Power-Down Mode
Threshold Voltage MAX8725 0.06 VMAX1909 0.85 ICTL Power-Up Mode Threshold
Voltage MAX8725 0.11 VINPUT CURRENT REGULATIONCSSP-to-CSSN Full-Scale
Current-Sense Voltage 72.75 77.25 mVVCLS = REF -3 +3VCLS = REF x 0.75 -3 +3Input Current-Limit AccuracyVCLS = REF x 0.5 -4 +4%CSSP/CSSN Input Voltage Range 8.0 28 V
CSSP/CSSN Input Current VCSSP = VCSSN = VDCIN > 8.0V 730 µACLS Input Range 1.6 REF VIINP Transconductance VCSSP - VCSSN = 56mV 2.7 3.3 mA/VVCSSP - VCSSN = 75mV, terminated with
10kΩ -7.5 +7.5VCSSP - VCSSN = 56mV, terminated with
10kΩ -5 +5IINP AccuracyVCSSP - VCSSN = 20mV, terminated with
10kΩ -10 +10%IINP Output Current VCSSP - VCSSN = 150mV, VIINP = 0V 350 µAIINP Output Voltage VCSSP - VCSSN = 150mV, VIINP = float 3.5 V
SUPPLY AND LINEAR REGULATORDCIN Input Voltage Range VDCIN 8.0 28 VDCIN falling 7 D C IN U nd er vol tag e- Lockout Tr i p oi nt DCIN rising 7.85 VDCIN Quiescent Current IDCIN 8.0V < VDCIN < 28V 6 mABATT Input Current IBATT VBATT = 2V to 19V, VDCIN > VBATT + 0.3V 500 µALDO Output Voltage 8.0V < VDCIN < 28V, no load 5.25 5.55 VLDO Load Regulation 0 < ILDO < 10mA 115 mV
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Electrical Characteristics (continued)
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, TA= -40°C to +85°C, unless otherwise noted.)
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITSLDO Undervoltage-Lockout Trip
Point VDCIN = 8.0V 3.20 5.15 V
REFERENCEREF Output Voltage Ref 0 < IREF < 500µA 4.1960 4.2520 VREF Undervoltage-Lockout Trip
Point REF falling 3.9 V
TRIP POINTSBATT POWER_FAIL Threshold VDCIN - VBATT, VDCIN falling 50 150 mVBATT POWER_FAIL Threshold
Hysteresis 100 300 mVACIN Threshold ACIN rising 2.007 2.089 VACIN Threshold Hysteresis 10 30 mV
SWITCHING REGULATOR
DHI Off-Time VBATT = 16.0V, VDCIN = 19V, VMODE = 3.6V 360 440 ns
DHI Minimum Off-Time VBATT = 16.0V, VDCIN = 17V, VMODE = 3.6V 260 350 nsDLOV Supply Current IDLOV DLO low 10 µASense Voltage for Battery
Undervoltage Charge Current MAX1909 only, BATT = 3.0V per cell 3 6 mVMAX1909 only, MODE = float (3 cell),
VBATT rising 9.18 9.42
Battery Undervoltage Threshold MAX1909 only, MODE = LDO (4 cell),
VBATT rising 12.235 12.565VDHIV Output Voltage With respect to SRC -4.5 -5.5 VDHIV Sink Current 10 mADHI On-Resistance Low DHI = VDHIV, IDHI = -10mA 5 ΩDHI On-Resistance High DHI = VCSSN, IDHI = 10mA 4 ΩDLO On-Resistance High VDLOV = 4.5V, IDLO = +100mA 7 ΩDLO On-Resistance Low VDLOV = 4.5V, IDLO = -100mA 3 Ω
ERROR AMPLIFIERSV C TL = 3.6, V BATT = 16.8V , M OD E = LD O 0.0625 0.2500 GMV Loop Transconductance V C TL = 3.6, V BATT = 12.6V , M OD E = FLOAT 0.0833 0.3330 mA/VGMI Loop Transconductance MAX1909: ICTL = 3.6V, MAX8725: VICTL =
3.2V, VCSSP - VCSIN = 75mV 0.5 2.0 mA/VGMS Loop Transconductance VCLS = 2.048V, VCSSP - VCSSN = 75mV 0.5 2.0 mA/VCCI/CCS/CCV Clamp Voltage 0.25V < VCCV < 2.0V, 0.25V < VCCI < 2.0V,
0.25V < VCCS < 2.0V 150 600 mV
LOGIC LEVELSMODE Input Low Voltage 0.8 VMODE Input Middle Voltage 1.6 2.0 V
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Electrical Characteristics (continued)
(Circuit of Figure 1, VDCIN= VCSSP= VCSSN= 18V, VBATT= VCSIP= VCSIN= 12V, VVCTL= VICTL= 1.8V, MODE = float, ACIN = 0, CLS =
REF, GND = PGND = 0, PKPRES= GND, LDO = DLOV, TA= -40°C to +85°C, unless otherwise noted.)
PARAMETERSYMBOLCONDITIONS MIN TYP MAX UNITSMODE Input High Voltage 2.8 V
ACOK AND PKPRESACOK Input Voltage Range 0 28 VACOK Sink Current VACOK = 0.4V, ACIN = 1.5V 1 mAPKPRES Input Voltage Range 0 LDO VPKPRES Battery Removal Detect
Threshold MAX8725, PKPRES rising 55 % of
LDO
PDS, PDL SWITCH CONTROLPDS Switch Turn-Off Threshold VDCIN - VBATT, VDCIN falling 50 150 mVP D S S w i tch Thr eshol d H yster esi s VDCIN - VBATT 100 300 mVPDS Output Low Voltage, PDS
Below SRC IPDS = 0A 8 12 VPDS Turn-On Current PDS = SRC 6 mAPDS Turn-Off Current VPDS = VSRC - 2V, VDCIN = 16V 10 mAPDL Switch Turn-On Threshold VDCIN - VBATT, VDCIN falling 50 150 mVP D L S w i tch Thr eshol d H yster esi s VDCIN - VBATT 100 300 mVPDL Turn-On Resistance PDL = GND 50 150 kΩPDL Turn-Off Current VSRC - VPDL = 1.5V 6 mASRC Input Bias Current SRC = 19, VBATT = 16V 1000 µA
Note 1:Guaranteed by design. Not production tested.
BATTERY INSERTION
AND REMOVAL RESPONSE
MAX1909/MAX8725 toc01
500μs/div
16V
17V
IIN
IBATT
VBATT
VCCI, VCCV
5A/div
5A/div
VCCI
VCCV
VCCV
VCCV
VCCI
VCCI
SYSTEM LOAD-TRANSIENT RESPONSE
MAX1909/MAX8725 toc02
100μs/div
IBATT
IIN
ISYSTEMLOAD
VCCS
VCCI
CCS
CCI
Typical Operating Characteristics
(Circuit of Figure 2, VDCIN= 20V, charge current = 3A, 4 Li+ series cells, TA= +25°C, unless otherwise noted.)
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
LDO LOAD REGULATION
MAX1909/MAX8725 toc04
LDO CURRENT (mA)
LDO OUTPUT ERROR (%)87654321
LINE-TRANSIENT RESPONSE
MAX1909/MAX8725 toc03
500μs/div
1.8V
VBATT AC-COUPLED
200mV/div
INDUCTOR CURRENT
200mA/div
1.6V
20V
30V
VDCIN
VCCV
REF vs. TEMPERATURE
MAX1909/MAX8725 toc07
TEMPERATURE (°C)
REF OUTPUT ERROR (%)3510-15
EFFICIENCY vs. CHARGE CURRENT
MAX1909/MAX8725 toc08
CHARGE CURRENT (A)
EFFICIENCY (%)
4 CELLS
3 CELLS
LDO LINE REGULATION
MAX1909/MAX8725 toc05
INPUT VOLTAGE (V)
LDO OUTPUT ERROR (%)10
REF LOAD REGULATION
MAX1909/MAX8725 toc06
REF CURRENT (μA)
REF OUTPUT ERROR (%)
Typical Operating Characteristics (continued)
(Circuit of Figure 2, VDCIN= 20V, charge current = 3A, 4 Li+ series cells, TA= +25°C, unless otherwise noted.)
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
SWITCHING FREQUENCY vs. VIN - VBATT
MAX1909/MAX8725 toc09
VIN - VBATT (V)
SWITCHING FREQUENCY (kHz)642
IINP ERROR vs. INPUT CURRENT
MAX1909/MAX8725 toc10
INPUT CURRENT (A)
IINP (%)
CHARGER
DISABLED
INPUT CURRENT-LIMIT ACCURACY vs. VCLS
MAX1909/MAX8725 toc14
VCLS (V)
INPUT CURRENT-LIMIT ACCURACY (%)
IINP ACCURACY vs. INPUT CURRENT
MAX1909/MAX8725 toc11
INPUT CURRENT (A)
IINP ACCURACY (%)
INPUT CURRENT-LIMIT ACCURACY
vs. SYSTEM LOAD
MAX1909/MAX8725 toc12
SYSTEM LOAD (A)
INPUT CURRENT-LIMIT ACCURACY (%)
VBATT = 10V
VBATT = 13V
VBATT = 12V
VBATT = 16V
ICHARGE = 3A
MAX1909 ONLY
INPUT CURRENT-LIMIT ACCURACY
vs. SYSTEM LOAD
MAX1909/MAX8725 toc13
SYSTEM LOAD (A)
INPUT CURRENT-LIMIT ACCURACY (%)
VBATT = 16VVBATT = 12V
VBATT = 13VVBATT = 10V
Typical Operating Characteristics (continued)
(Circuit of Figure 2, VDCIN= 20V, charge current = 3A, 4 Li+ series cells, TA= +25°C, unless otherwise noted.)
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
PDL-PDS SWITCHING,
AC ADAPTER INSERTION
MAX1909/MAX8725 toc15
100μs/div
10V
20V
10V
20V
10V
20V
VWALLADAPTER
VSYSTEMLOAD, VPDS
VPDS
VPDL, VBATT
VPDLSYSTEM LOAD
VPDL
VPDS
PDS-PDL SWITCHOVER,
WALL ADAPTER REMOVAL
MAX1909/MAX8725 toc16
500μs/div
10V
20V
10V
20V
10V
20V
VWALLADAPTER
VSYSTEMLOAD
VSYSTEMLOAD
VPDS
VPDL
VBATT
VPDL
PDS-PDL SWITCHOVER,
BATTERY INSERTION
MAX1909/MAX8725 toc17
50μs/div
10V
15V
10V
15V
20V
VSYSTEM
VPDS
VPDL
VBATT
VPKDET
CONDITIONING MODE
WALL ADAPTER = 18V
VPKPRES
PDL-PDS SWITCHING,
BATTERY REMOVAL
MAX1909/MAX8725 toc18
10μs/div
10V
15V
10V
15V
20V
VSYSTEM
VPDS
VPDL
VBATT
CONDITIONING MODE
WALL ADAPTER = 18V
VPKPRES
MAX8725 ONLY
Typical Operating Characteristics (continued)
(Circuit of Figure 2, VDCIN= 20V, charge current = 3A, 4 Li+ series cells, TA= +25°C, unless otherwise noted.)
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
Pin Description
PINNAMEFUNCTIONDCIN DC Supply Voltage Input. Bypass DCIN with a 1μF capacitor to power ground. LDO Device Power Supply. Output of the 5.4V linear regulator supplied from DCIN. Bypass with a 1μF capacitor.
3 ACIN AC Detect Input. This uncommitted comparator input can be used to detect the presence of the charger’s
power source. The comparator’s open-drain output is the ACOK signal. REF 4.2235V Voltage Reference. Bypass with a 1μF capacitor to GND.
GNDMAX1909: Ground this pin. 5PKPRESMAX8725: Pull PKPREShigh to disable charging. Used for detecting presence of battery pack.
6 ACOK AC Detect Output. High-voltage open-drain output is high impedance when ACIN is greater than 2.048V.
The ACOK output remains a high impedance when the MAX1909/MAX8725 are powered down.
7 MODE
Trilevel Input for Setting Number of Cells and Asserting the Conditioning Mode:
MODE = GND; asserts conditioning mode.
MODE = float; charge with 3 times the cell voltage programmed at VCTL.
MODE = LDO; charge with 4 times the cell voltage programmed at VCTL.
8 IINP
Input Current Monitor Output. The current delivered at the IINP output is a scaled-down replica of the
system load current plus the input-referred charge current sensed across CSSP and CSSN inputs. The
transconductance of (CSSP - CSSN) to IINP is 3mA/V. CLS Source Current-Limit Input. Voltage input for setting the current limit of the input source.
10 ICTL Input for Setting Maximum Output Current
11 VCTL Input for Setting Maximum Output Voltage
12 CCI Output Current-Regulation Loop-Compensation Point. Connect 0.01μF to GND.
13 CCV Voltage-Regulation Loop-Compensation Point. Connect 10k in series with 0.1μF to GND.
14 CCS Input Current-Regulation Loop-Compensation Point. Use 0.01μF to GND.
15 GND Analog Ground
16 BATT Battery Voltage Feedback Input
17 CSIN Output Current-Sense Negative Input
18 CSIP Output Current-Sense Positive Input. Connect a current-sense resistor from CSIP to CSIN.
19 PGND Power Ground
20 DLO Low-Side Power-MOSFET Driver Output. Connect to low-side NMOS gate. When the MAX1909/MAX8725 are
shut down, the DLO output is low.
21 DLOV Low-Side Driver Supply. Bypass with a 1μF capacitor to ground.
22 DHIV High-Side Driver Supply. Bypass with a 0.1μF capacitor to SRC.
23 DHI High-Side Power-MOSFET Driver Output. Connect to high-side PMOS gate. When the MAX1909/MAX8725
are shut down, the DHI output is high.
24 SRC Source Connection for Driver for PDS/PDL Switches. Bypass SRC to power ground with a 1μF capacitor.
25 CSSN Input Current Sense for Charger (Negative Input)
26 CSSP Input Current Sense for Charger (Positive Input). Connect a current-sense resistor from CSSP to CSSN.
27 PDS Power-Source PMOS Switch Driver Output. When the MAX1909/MAX8725 are powered down, the PDS output
is pulled to SRC through an internal 1M resistor.
28 PDL System-Load PMOS Switch Driver Output. When the MAX1909/MAX8725 are powered down, the PDL output
is pulled to ground through an internal 100k resistor.
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
CSSPCSSN
LDO
DHI
DLOV
DLO
PGND
CSIP
CSIN
BATT
GND
DCIN
VCTL
ICTL
MODE
ACIN
ACOK
CLS
CCV
CCI
CCSREF
GND
HOST
SYSTEM
BATT +
TEMP
BATT -
BATTERY
AC ADAPTER
590kΩR7
196kΩC5
1µFRS1
0.01Ω
10kΩ
C11
0.1µF
C10
0.01µF
0.01µFC12
1µF
22µF
C16
1µF
C13
1µFR13
33Ω
22µF
GNDPGND
RS2
0.015Ω
SYSTEM LOAD
1MΩ
LDO
OUTPUT
(INPUT I LIMIT: 7.5A)
OUTPUT VOLTAGE: 12.6V
CHARGE I LIMIT: 3.0A
PDS
PDL
SRC
LDO
REF
DHIV
C17
0.1µF
100kΩ
SRC
C22
1µF
10kΩ
MAX1909
MAX8725
PKPRES (MAX8725 ONLY)
10µH
LDO
LDO
0.1µF0.1µF
Figure 1. Typical Operating Circuit Demonstrating Hardwired Control
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
CSSPCSSN
LDO
DHI
DLOV
DLO
PGND
CSIP
CSIN
BATT
GND
DCIN
VCTL
ICTL
ACIN
MODE
ACOK
IINP
CCV
CCI
CCSREFAVDD/REF
SCL
SDA
GND
HOST
BATT +
TEMP
SDA
SCL
BATT -
SMART
BATTERY
AC ADAPTER
590kΩR7
196kΩC5
1µFP4RS1
0.01Ω
10kΩ
C11
0.1µF
C10
0.01µF
0.01µF
C12
1µF
22µF
C16
1µF
C13
1µFR13
33Ω
22µF
GNDPGND
RS2
0.015Ω
SYSTEM LOAD
1MΩ
LDO
OUTPUTS
OUTPUT
INPUT
A/D INPUT
OPEN-DRAIN
OUTPUT VOLTAGE: 16.8V
PDS
PDL
SRC
LDO
CLSREF
DHIV
C17
0.1µF
SRC
C15
1µF
R21
10kΩ
MAX1909
MAX8725
C14
0.1µF
10kΩ
R19, R20
10kΩ
(INPUT I LIMIT: 7.5A)
10µH
D/A OUTPUT
0.1µF0.1µF
LDO
PKPRES (MAX8725 ONLY)
Figure 2. Smart-Battery Charger Circuit Demonstrating Operation with a Host Microcontroller
MAX1909/MAX8725Multichemistry Battery Chargers with
Automatic System Power Selector
CHG
LOGIC
5.4V
LINEAR
REGULATOR
4.2235V
REFERENCE
LDO
DCIN
REF
ACOK
2.048V
IINP
DC-DC
CONVERTER
PDS
DHI
PDL
DRIVER
DRIVER
DRIVER
DRIVER
DLOV
DLO
PGND
LVC
BATT
MODE
VCTL
CSIP
CSIN
LEVEL
SHIFTER
LEVEL
SHIFTER
CSSP
CSSN
ICTL
CLS
SRDY
GND
GND
GMV
GMI
GMS
CCS
CCI
CCV
CELL SELECT
LOGIC AND
BATTERY VOLTAGE-
DIVIDER
ACIN
0.9 * LDO
RDY
SRC
SWITCH LOGIC
REF
MODE
DHIV
DCIN
0.8V
BATT
PKPRES
3.0V/CELL
BATT_UV
ICTLOK
PACK_ON
CHG
SRC
MAX1909
MAX8725
SRC-10V
100kΩ
MAX1909 ONLY
MAX8725 ONLY
Figure 3. Functional Diagram

Partno	Mfg	Dc	Qty	Available	Descript
MAX1909ETI+ \|MAX1909ETI	MAX	N/a	10	avai	Multichemistry Battery Chargers with Automatic System Power Selector
MAX1909ETI+T \|MAX1909ETIT	MAXIM	N/a	1220	avai	Multichemistry Battery Chargers with Automatic System Power Selector
MAX8725ETI+ \|MAX8725ETI	MAXIM	N/a	7397	avai	Multichemistry Battery Chargers with Automatic System Power Selector
MAX8725ETI+ \|MAX8725ETI	MAXIN	N/a	1606	avai	Multichemistry Battery Chargers with Automatic System Power Selector
MAX8725ETI+T	MAXIM	N/a	3438	avai	Multichemistry Battery Chargers with Automatic System Power Selector