MAX8903HETI+T ,2A 1-Cell Li+ DC-DC Charger for USB and Adapter PowerFeatures♦ Efficient DC-DC Converter Eliminates HeatThe MAX8903A–MAX8903E/MAX8903G/MAX8903H/MAX8903J ..
MAX8903HETI+TC64 ,2A 1-Cell Li+ DC-DC Charger for USB and Adapter PowerEVALUATION KIT AVAILABLE MAX8903A–E/G/H/J/N/Y2A 1-Cell Li+ DC-DC Chargersfor USB and Adapter Power
MAX890L ,1.2A, Current-Limited, High-Side P-Channel Switch with Thermal ShutdownApplications Ordering InformationPCMCIA SlotsTEMP. PIN- CURRENTPART*RANGE PACKAGE LIMITAccess Bus S ..
MAX890LESA ,1A / Current-Limited / High-Side P-Channel Switch with Thermal ShutdownFeaturesThe MAX890L smart, low-voltage, P-channel, MOSFET' 2.7V to 5.5V Input Rangepower switch is ..
MAX890LESA ,1A / Current-Limited / High-Side P-Channel Switch with Thermal Shutdownapplications. This switch operates with inputs from 2.7Vto 5.5V, making it ideal for both 3V and 5V ..
MAX890LESA ,1A / Current-Limited / High-Side P-Channel Switch with Thermal ShutdownApplicationsOrdering InformationPCMCIA SlotsTEMP. PIN- CURRENTPART*RANGE PACKAGE LIMITAccess Bus Sl ..
MB88101A ,A/D Converter (With 4-channel Input at 12-bit Resolution)FEATURES• 4-channel analog input• One analog input channel selectable for conversion by external co ..
MB88101A ,A/D Converter (With 4-channel Input at 12-bit Resolution)FUJITSU SEMICONDUCTORDS04-13105-2EDATA SHEETLinear IC ConverterCMOSA/D Converter(With 4-channel I ..
MB88101APF ,A/D Converter (With 4-channel Input at 12-bit Resolution)FEATURES• 4-channel analog input• One analog input channel selectable for conversion by external co ..
MB88141 ,D/A Converter for Digital Tuning (With Built-in OP Amp and I/O Expander)FUJITSU SEMICONDUCTORDS04-13211-3EDATA SHEETGeneral Purpose Linear IC’s General Purpose ConvertersC ..
MB88141A ,D/A Converter for Digital Tuning (Compatible with I 2 C Bus)FUJITSU SEMICONDUCTORDS04-13213-1EDATA SHEETLinear IC ConverterCMOSD/A Converter for Digital Tuning ..
MB88141APF ,D/A Converter for Digital Tuning (Compatible with I2C Bus)FUJITSU SEMICONDUCTORDS04-13213-1EDATA SHEETLinear IC ConverterCMOSD/A Converter for Digital Tuning ..
MAX8903AETI+-MAX8903AETI+T-MAX8903BETI+-MAX8903BETI+T-MAX8903CETI+-MAX8903CETI+T-MAX8903HETI+T-MAX8903HETI+TC64
2A 1-Cell Li+ DC-DC Charger for USB and Adapter Power
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter PowerEVALUATION KIT AVAILABLE
General DescriptionThe MAX8903A–MAX8903E/MAX8903G/MAX8903H/
MAX8903J/MAX8903N/MAX8903Y are integrated 1-cell
Li+ chargers and Smart Power Selectors™ with dual
(AC adapter and USB) power inputs. The switch mode
charger uses a high switching frequency to eliminate
heat and allow tiny external components. It can operate
with either separate inputs for USB and AC adapter
power, or from a single input that accepts both. All
power switches for charging and switching the load
between battery and external power are included on-
chip. No external MOSFETs, blocking diodes, or cur-
rent-sense resistors are required.
The MAX8903_ features optimized smart power control
to make the best use of limited USB or adapter power.
Battery charge current and SYS output current limit are
independently set. Power not used by the system
charges the battery. Charge current and SYS output cur-
rent limit can be set up to 2A while USB input current can
be set to 100mA or 500mA. Automatic input selection
switches the system from battery to external power. The
DC input operates from 4.15V to 16V with up to 20V pro-
tection, while the USB input has a range of 4.1V to 6.3V
with up to 8V protection.
The MAX8903_ internally blocks current from the bat-
tery and system back to the DC and USB inputs when
no input supply is present. Other features include pre-
qual charging and timer, fast charge timer, overvoltage
protection, charge status and fault outputs, power-OK
monitors, and a battery thermistor monitor. In addition,
on-chip thermal limiting reduces battery charge rate
and AC adapter current to prevent charger overheat-
ing. The MAX8903_is available in a 4mm x 4mm, 28-pin
thin QFN package.
The various versions of the MAX8903_ allow for design
flexibility to choose key parameters such as system
regulation voltage, battery prequalification threshold,
and battery regulation voltage. The MAX8903B/
MAX8903E/MAX8903G also includes power-enable on
battery detection. See the Selector Guidesection for
complete details.
Applications
FeaturesEfficient DC-DC Converter Eliminates Heat4MHz Switching for Tiny External ComponentsInstant On—Works with No/Low BatteryDual Current-Limiting Inputs—AC Adapter or USBAutomatic Adapter/USB/Battery Switchover to
Support Load Transients50mΩSystem-to-Battery Switch
Supports USB SpecThermistor MonitorIntegrated Current-Sense ResistorNo External MOSFETs or Diodes4.1V to 16V Input Operating Voltage Range
Selector Guide appears at end of data sheet.CHARGE
AND
SYS LOAD
SWITCHSYS
BAT
ADAPTER
OR USB
SYSTEM
LOAD
BATTERY
GND
USBUSB
CHARGE
CURRENT
LOAD
CURRENTCS
PWM
STEP-DOWN
MAX8903_
Typical Operating CircuitPDAs, Palmtops, andWireless Handhelds
Personal NavigationDevices
Smart Cell Phones
Portable MultimediaPlayers
Mobile Internet Devices
Ultra Mobile PCs
Ordering Information+Denotes a lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
T = Tape and reel.
PARTTEMP RANGEPIN-PACKAGE
MAX8903AETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903BETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903CETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903DETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903EETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903GETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903HETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903JETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903NETI+T-40°C to +85°C28 Thin QFN-EP*
MAX8903YETI+T-40°C to +85°C28 Thin QFN-EP*
Visit www.maximintegrated.com/products/patentsfor
product patent marking information.
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
ELECTRICAL CHARACTERISTICS(VDC= VUSB= 5V, VBAT= 4V, circuit of Figure 2, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
(Note 1)
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.
PARAMETERCONDITIONSMINTYPMAXUNITS
DC INPUTDC Operating Range4.1516V
No valid USB input3.94.04.1DC Undervoltage ThresholdWhen VDOK goes low, VDC
rising, 500mV typical hysteresisValid USB input4.04.34.4V
DC Overvoltage ThresholdWhen VDOK goes high, VDC rising, 500mV typical
hysteresis16.51717.5V
Charger enabled, no switching, VSYS = 5V2.34
Charger enabled, f = 3MHz, VDC = 5V15har g er enab l ed , V C E N = 0V , 100m A U S B m od e ( N ote 2) 12har g er enab l ed , V C E N = 5V , 100m A U S B m od e ( N ote 2) 12
DC Supply Current
VDCM = 0V, VUSUS = 5V0.100.25
DC High-Side Resistance0.15Ω
DC Low-Side Resistance0.15Ω
DC-to-BAT Dropout ResistanceAssumes a 40mΩ inductor resistance (RL)0.31Ω
DC-to-BAT Dropout VoltageWhen SYS regulation and charging stops, VDC falling,
200mV hysteresis01530mV
Minimum Off Time (tOFFMIN)100ns
Minimum On Time (tONMIN)70ns
VDC = 8V, VBAT = 4V4MAX8903A/B/C/D/E/H/J/YVDC = 5V, VBAT = 3V3
VDC = 9V, VBAT = 4V1Switching Frequency (fSW)
MAX8903GVDC = 9V, VBAT = 3V1
MHz
DC Step-Down Output Current-
Limit Step Range0.52A
RIDC = 3kΩ190020002100
RIDC = 6kΩ95010001050DC Step-Down Output CurrentVDC = 6V, VSYS = 4V
ABSOLUTE MAXIMUM RATINGSDC, LX to GND.......................................................-0.3V to +20V
DCM to GND..............................................-0.3V to (VDC+ 0.3V)
DC to SYS .................................................................-6V to +20V
BST to GND ...........................................................-0.3V to +26V
BST TO LX................................................................-0.3V to +6V
USB to GND.............................................................-0.3V to +9V
USB to SYS..................................................................-6V to +9V
VL to GND................................................................-0.3V to +6V
THM, IDC, ISET, CT to GND........................-0.3V to (VVL+ 0.3V)
DOK, FLT, CEN, UOK, CHG, USUS,
BAT, SYS, IUSB, CS to GND................................-0.3V to +6V
SYS to BAT...............................................................-0.3V to +6V
PG, EP (exposed pad) to GND.............................-0.3V to +0.3V
DC Continuous Current (total in two pins)......................2.4ARMS
USB Continuous Current.......................................................1.6A
LX Continuous Current (total in two pins).......................2.4ARMS
CS Continuous Current (total in two pins)......................2.4ARMS
SYS Continuous Current (total in two pins).......................3ARMS
BAT Continuous Current (total in two pins).......................3ARMS
VL Short Circuit to GND.............................................Continuous
Continuous Power Dissipation (TA= +70°C)
28-Pin Thin QFN-EP
Multilayer (derate 28.6mW/°C above +70°C)..........2286mW
28-Pin Thin QFN-EP
Single-Layer (derate 20.8mW/°C above +70°C)...1666.7mW
Operating Temperature Range...........................-40°C to +85°C
Junction Temperature Range............................-40°C to +150°C
Storage Temperature Range.............................-65°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
Soldering Temperature (reflow).......................................+260°C
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
PARAMETERCONDITIONSMINTYPMAXUNITSNo valid USB input1msDC Soft-Start TimeValid USB input before soft-start20µs
DC Output Current
500mA USB Mode (Note 3)VDCM = 0V, VIUSB = 5V450475500mA
DC Output Current
100mA USB Mode (Note 2)VDCM = 0V, VIUSB = 0V9095100mA
SYS to DC Reverse Current
BlockingVSYS = 5.5V, VDC = 0V0.01µA
USB INPUTUSB Operating Range4.16.3V
USB Standoff Voltage8V
USB Undervoltage ThresholdWhen VUOK goes low, VUSB rising, 500mV hysteresis3.954.04.05V
USB Overvoltage ThresholdWhen VUOK goes high, VUSB rising, 500mV hysteresis6.86.97.0V
VIUSB = 0V (100mA setting)9095100USB Current LimitVIUSB = 5V (500mA setting)450475500mA
ISYS = IBAT = 0mA, VCEN = 0V1.33
ISYS = IBAT = 0mA, VCEN = 5V0.82USB Supply Current
VUSUS = 5V (USB suspend mode)0.1150.25
Minimum USB to BAT Headroom01530mV
USB to SYS Dropout Resistance0.20.35Ω
VUSB rising1msUSB Soft-Start TimeVDC falling below DC UVLO to initiate USB soft-start20µs
SYS OUTPUTMAX8903A/B/E/G/Y3.0Minimum SYS Regulation Voltage
(VSYSMIN)
ISYS = 1A,
VBAT < VSYSMINMAX8903C/D/H/J/N3.4V
MAX8903A/C/D/H/N/Y4.34.44.5
MAX8903B/E/G4.2654.3254.395Regulation VoltageISYS = 0A
MAX8903J4.44.54.55
MAX8903A/C/D/H40Load RegulationISYS = 0 to 2AMAX8903B/E/G/J/N/Y25mV/A
CS to SYS ResistanceVDC = 6V, VDCM = 5V, VSYS = 4V, ICS = 1A0.07Ω
SYS to CS LeakageVSYS = 5.5V, VDC = VCS = 0V0.01µA
BAT to SYS ResistanceVDC = VUSB = 0V, VBAT = 4.2V, ISYS = 1A0.050.1Ω
BAT to SYS Reverse Regulation
VoltageVUSB = 5V, VDC = 0V, VIUSB = 0V, ISYS = 200mA5075100mV
SYS Undervoltage ThresholdSYS falling, 200mV hysteresis (Note 4)1.81.92.0V
ELECTRICAL CHARACTERISTICS (continued)(VDC= VUSB= 5V, VBAT= 4V, circuit of Figure 2, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
(Note 1)
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
PARAMETERCONDITIONSMINTYPMAXUNITS
BATTERY CHARGERTA = +25°C4.1794.2004.221MAX8903A/B/C/G/HTA = -40°C to +85°C4.1584.2004.242
TA = +25°C4.0794.1004.121MAX8903D/ETA = -40°C to +85°C4.0594.1004.141
TA = +25°C4.3284.3504.372MAX8903JTA = -40°C to +85°C4.3074.3504.394
TA = +25°C4.1294.1504.171
BAT Regulation Voltage
(VBATREG) IBAT = 0mA
MAX8903Y/NTA = -40°C to +85°C4.1094.1504.192har g er Restar t Thr eshol d Change in VBAT from DONE to fast-charge-150-100-60mV
MAX8903A/C/D/H/J/N/Y2.93.03.1BAT Prequal Threshold (VBATPQ)VBAT rising 180mV
hystersisMAX8903B/E/G2.42.52.6V
Prequal Charge CurrentPercentage of fast-charge current set at ISET10%
RISET = 600Ω180020002200
RISET = 1.2kΩ (MAX8903A/C/D)90010001100Fast-Charge Current
RISET = 2.4kΩ450500550
DONE Threshold (ITERM)Percentage of fast-charge, IBAT decreasing10%
RISET Resistor Range0.62.4kΩ
ISET Output Voltage1.5V
ISET Current Monitor Gain1.25mA/A
No DC or USB input0.054BAT Leakage CurrentWith valid input power, VCEN = 5V36µA
Charger Soft-Start Time1.0ms
Charger Thermal Limit
Temperature100°C
Charger Thermal Limit GainCharge current = 0 at + 120°C5%/°C
CHARGER TIMERPrequalification TimeCCT = 0.15µF33min
Fast-Charge TimeCCT = 0.15µF660min
MAX8903A/C/D/H/J/N/Y (fixed)15sTop-Off Timer (tTOP-OFF)MAX8903B/E/G, CCT = 0.15µF132min
Timer Accuracy-15+15%
Timer Extend Current ThresholdPercentage of fast-charge current below which the timer
clock operates at half-speed405060%
Timer Suspend Current ThresholdPercentage of fast-charge current below which timer
clock pauses162024%
ELECTRICAL CHARACTERISTICS (continued)(VDC= VUSB= 5V, VBAT= 4V, circuit of Figure 2, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
(Note 1)
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
PARAMETERCONDITIONSMINTYPMAXUNITS
THERMISTOR MONITORTHM Threshold, HotWhen charging is suspended, 1% hysteresis0.27 x
VVL
0.28 x
VVL
0.29 x
VVLV
THM Threshold, ColdWhen charging is suspended, 1% hysteresis0.73 x
VVL
0.74 x
VVL
0.75 x
VVLV
THM Threshold, DisabledTHM function is disabled below this voltage0.0254
x VVL
0.03 x
VVL
0.036 x
VVLV
THM Threshold DC, USB EnableMAX8903B/MAX8903E/MAX8903G0.83 x
VVL
0.87 x
VVL
0.91 x
VVLV
THM = GND or VL;
TA = +25°C-0.100±0.001+0.200
MAX8903A/C/D/H/J/N/Y
THM = GND or VL;
TA = +85°C±0.010THM Input Leakage
MAX8903B/E/GTHM = GND or VL;
TA = -40°C to +85°C-0.200±0.001+0.200
THERMAL SHUTDOWN, VL, AND LOGIC I/O: CHG, FLT, DOK, UOK, DCM, CEN, USUS, IUSBHigh level1.3
Low level0.4VLogic-Input Thresholds
(DCM, CEN, USUS, IUSB)
Hysteresis50mV
TA = +25°C-1.000±0.001+1.000VINPUT = 0V to 5.5V
(MAX8903A/C/D/H/J/N/Y)TA = +85°C±0.010Logic-Input Leakage Current
(CEN, USUS, IUSB)VINPUT = 0V to 5.5V
(MAX8903B/E/G)TA = -40°C to +85°C-0.200±0.001+0.200
TA = +25°C0.0011Logic-Input Leakage Current
(DCM)
VDCM = 0V to 16V
VDC = 16VTA = +85°C0.01µA
Sinking 1mA850Logic Output Voltage, Low
(CHG, FLT, DOK, UOK)Sinking 10mA80mV
TA = +25°C0.0011Open-Drain Output Leakageur rent, Hi g h (CHG , FLT, DOK, UOK) VOUT = 5.5VTA = +85°C0.01µA
ELECTRICAL CHARACTERISTICS (continued)(VDC= VUSB= 5V, VBAT= 4V, circuit of Figure 2, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
(Note 1)
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
MAX8903A–E/G/H/J/N/Y
PARAMETERCONDITIONSMINTYPMAXUNITSIVL = 0 to 1mA
(MAX8903A/C/D/H/J/N/Y)4.65.05.4
VL Output VoltageVDC = VUSB = 6V
IVL = 0 to 10mA
(MAX8903B/E/G)4.65.05.4
VL UVLO ThresholdVVL falling; 200mV hysteresis3.2V
Thermal Shutdown Temperature160°C
Thermal Shutdown Hysteresis15°C
ELECTRICAL CHARACTERISTICS (continued)(VDC= VUSB= 5V, VBAT= 4V, circuit of Figure 2, TA= -40°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
(Note 1)
Note 1:Limits are 100% production tested at TA= +25°C. Limits over the operating temperature range are guaranteed by design.
Note 2:For the 100mA USB mode using the DC input, the step-down regulator is turned off and its high-side switch operates as a
linear regulator with a 100mA current limit. The linear regulator’s output is connected to LX and its output current flows
through the inductor into CS and finally to SYS.
Note 3:For the 500mA USB mode, the actual current drawn from USB is less than the output current due to the input/output current
ratio of the DC-DC converter.
Note 4:For short-circuit protection, SYS sources 25mA below VSYS= 400mV, and 50mA for VSYSbetween 400mV and 2V.
Typical Operating Characteristics(TA = +25°C, unless otherwise noted.)
MAX8903A/B/C/D/E/H/J/N/Y
BATTERY CHARGER EFFICIENCY
vs. BATTERY VOLTAGE
MAX8903A toc01
BATTERY VOLTAGE (V)
EFFICIENCY (%)
VDC = 8V
IBAT = 0.15AIBAT = 1.5A
VDC = 5V
VDC = 12V
MAX8903G BATTERY CHARGER
EFFICIENCY vs. BATTERY VOLTAGE
MAX8903A toc01a
BATTERY VOLTAGE (V)
EFFICIENCY (%)
VDC = 12V
IBATT = 0.15AIBATT = 1.5A
VDC = 6V
VDC = 9V
MAX8903A/B/C/D/E/H/J/N/Y
SWITCHING FREQUENCY vs. VDC
MAX8903A toc02
DC VOLTAGE (V)
SWITCHING FREQUENCY (MHz)
VBAT = 3V
RISET = 1.2kΩ
VCEN = 0V
VBAT = 4V
MAX8903G SWITCHING
FREQUENCY vs. VDC
MAX8903A toc02a
DC VOLTAGE (V)
SWITCHING FREQUENCY (MHz)126810
VBAT = 3V
VBAT = 4V
RISET = 1.2kI
VCEN = 0V
MAX8903A/B/C/D/E/H/J/N/Y
SYS EFFICIENCY
vs. SYS OUTPUT CURRENT
MAX8903A toc03
SYS OUTPUT CURRENT (mA)
SYS EFFICIENCY (%)
VCEN = 1V
VSYS = 4.4V
VDC = 4.5V
VDC = 6V
VDC = 11V
VDC = 16V
MAX8903G SYS EFFICIENCY
vs. SYS OUTPUT CURRENT
MAX8903A toc03a
SYS OUTPUT CURRENT (mA)
SYS EFFICIENCY (%)
10010,000
VDC = 16V
VDC = 12V
VDC = 9V
VDC = 6V
VCEN = 1
USB SUPPLY CURRENT
vs. USB VOLTAGE
MAX8903A toc04
USB VOLTAGE (V)
USB SUPPLY CURRENT (mA)
CHARGER
ENABLED
CHARGER
DISABLED
USB SUPPLY CURRENT
vs. USB VOLTAGE (SUSPEND)
MAX8903A toc05
USB VOLTAGE (V)
USB QUIESCENT CURRENT (
USB SUSPEND56321
BATTERY LEAKAGE CURRENT
vs. BATTERY VOLTAGEMAX8903A toc06
BATTERY VOLTAGE (V)
BATTERY LEAKAGE CURRENT (nA)
NO DC OR USB INPUT
BATTERY LEAKAGE CURRENT
vs. AMBIENT TEMPERATURE
MAX8903A toc07
BATTERY LEAKAGE CURRENT (nA)
NO DC OR USB INPUT
CHARGE CURRENT
vs. BATTERY VOLTAGE—USB MODE
MAX8903A toc08
CHARGE CURRENT (mA)
CHARGE ENABLED
IBAT SET TO 1.5A
MAX8903D
VBAT RISING
VIUSB = VUSB
VIUSB = 0V
CHARGE CURRENT
vs. BATTERY VOLTAGE—DC MODE
MAX8903A toc09
CHARGE CURRENT (mA)
CHARGER ENABLED
IBAT SET TO 1A
IDC SET TO 2A
MAX8903A/C/H
VBAT RISING
Typical Operating Characteristics (continued)(TA = +25°C, unless otherwise noted.)
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
NORMALIZED CHARGE CURRENT
vs. AMBIENT TEMPERATUREMAX8903A toc10
TEMPERATURE (°C)
NORMALIZED CHARGE CURRENT3510-15
VUSB = 5V, VBAT = 4V
NORMALIZED BATTERYREGULATION VOLTAGE
vs. AMBIENT TEMPERATURE
MAX8903A toc11
TEMPERATURE (°C)
NORMALIZED BATTERY REGULATION VOLTAGE (%)3510-15
22ppm/°C0
MAX8903A/C/D/H/N/Y
SYS VOLTAGE vs. USB VOLTAGE
MAX8903A toc12
USB VOLTAGE (V)
SYS VOLTAGE (V)
VUSB FALLING
VCEN = 5V
VBAT = 0V
VDC = 0V
VUSB RISING
RSYS = 1MΩ
MAX8903A/C/D/H/N/Y
SYS VOLTAGE vs. DC VOLTAGE
MAX8903A toc13
DC VOLTAGE (V)
SYS VOLTAGE (V)
VDC RISING
VDC FALLING
VCEN = 5V
VBAT = 0V
VUSB = 0V
SYS VOLTAGE
vs. SYS OUTPUT CURRENT, DC INPUT
MAX8903A toc14
SYS OUTPUT CURRENT (A)
SYS VOLTAGE (V)
VUSB = 0VMAX8903J, VDC = 5.75V
MAX8903N/Y,
VDC = 5.75V
MAX8903A/C/D/H,
VDC = 5.75V
MAX8903B/E/G,
VDC = 5.75V
MAX8903_, VDC = 0V
SYS VOLTAGE
vs. SYS OUTPUT CURRENT, USB INPUT
MAX8903A toc15
SYS OUTPUT CURRENT (mA)
SYS VOLTAGE (V)
VDC = 0V, VBATT = 4V
MAX8903J, VUSB = 5V
MAX8903N/Y,
VUSB = 5V
MAX8903A/C/D/H,
VUSB = 5V
MAX8903B/E/G,
VUSB = 5V
MAX8903_, VUSB = 0V
VL VOLTAGE vs. DC VOLTAGE
MAX8903A toc16
VL VOLTAGE (V)161412108642
VL WITH
NO LOAD AND
DCDC OFF
(VUSUS = 5V)
VL AND DCDC
WITH
FULL LOAD
(VUSUS = 0V)
VBAT = 3.6V
VUSB = 0V
CHARGE PROFILE—1400mAh BATTERY
ADAPTER INPUT—1A CHARGEMAX8903A toc17
BAT
(V)
IBAT
(A)
VBAT
IDC SET TO 1A
IBAT SET TO 2A
IBAT
MAX8903A/B/C/G/H
Typical Operating Characteristics (continued)(TA = +25°C, unless otherwise noted.)
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
MAX8903A/B/C/G/HCHARGE PROFILE—1400mAh BATTERY USB INPUT—500mA CHARGETIME (min)
BAT
(V)
IBAT
(A)
VBAT
IBAT
MAX8903A toc18
MAX8903A/MAX8903B/MAX8903C
IUSB SET TO 500mA
IBAT SET TO 2A
200ns/div
MAX8903A/B/C/D/E/H/J/N/Y DC SWITCHING
WAVEFORMS—LIGHT LOAD20mV/div
AC-COUPLED
MAX8903A toc19
500mA/div
5V/div
VOUT
VLX
ILX
RSYS = 44Ω
MAX8903G DC SWITCHING
WAVEFORMS—LIGHT LOAD
MAX8903A toc19a
10V/div
50mV/div
AC-COUPLED
1A/div
VSYS
VLX
ILX
1µs/div
VDC = 9V, L = 2.2µH
CSYS = 22µF,
RSYS = 44I
MAX8903A/B/C/D/E/H/J/N/Y DC SWITCHING
WAVEFORMS—HEAVY LOADMAX8903A toc20
200ns/div
VLX
VOUT
ILX
5V/div
20mV/div
AC-COUPLED
500mA/div
RSYS = 5Ω
MAX8903G DC SWITCHING
WAVEFORMS—HEAVY LOAD
MAX8903A toc20a
10V/div
50mV/div
AC-COUPLED
1A/div
VSYS
VLX
ILX
VDC = 9V, L = 2.2µH
CSYS = 22µF, RSYS = 5I
CEN = 1
DC CONNECT WITH
USB CONNECTED (RSYS = 25Ω)MAX8903A toc21
IDC
VSYS
IUSB
IBAT
2V/div
500mA/div
500mA/div
500mA/div
3.6V
347mA
-IBAT = CHARGING
475mA
-335mA
Typical Operating Characteristics (continued)(TA = +25°C, unless otherwise noted.)
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power400µs/div
DC CONNECT WITH NO USB
(RSYS = 25Ω)2V/div
MAX8903A toc22
5V/div
1A/div
1A/div
3.6V3.84V
3.6V3.44V
CDC
CHARGINGCSYS
CHARGING850mA
-1A
BATTERY
CHARGER
SOFT-START
144mA
VSYS
VBAT
IDC
IBAT-IBAT = CHARGING
40µs/div
DC DISCONNECT WITH NO USB
(RSYS = 25Ω)2V/div
MAX8903A toc23
5V/div
1A/div
1A/div
3.6V3.68V
850mA
-1A144mA
VSYS
VBAT
IDC
IBAT
3.6V
-IBAT = CHARGING
MAX8903A/C/D/H SYS LOAD TRANSIENT
MAX8903A toc24a
20mV/div
AC-COUPLED
500mA/div
VSYS
4.400V
4.360V
ISYS
100µs/div
MAX8903A
VDC = 10.5V
L = 2.2µH
CSYS = 10µF
RIDC = 3kI (2A)
DCM = HIGH
CEN = 1
MAX8903B/E SYS LOAD TRANSIENT
MAX8903A toc24b
20mV/div
500mA/div
VSYS
4.325V
4.305V
ISYS
100µs/div
MAX8903B
VDC = 10.5V
L = 2.2µH
CSYS = 22µF
RIDC = 3kI (2A)
DCM = HIGH
CEN = 1
MAX8903G SYS LOAD TRANSIENT
MAX8903A toc24c
50mV/div
500mA/div
VSYS
4.325V
4.305V
ISYS
VDC = 9V
L = 2.2µH
CSYS = 22µF
RIDC = 3kI (2A)
DCM = 1
CEN = 1
USB CONNECT WITH NO DC
(RSYS = 25Ω)2V/div
MAX8903A toc25
5V/div
500mA/div
500mA/div
3.6V
CUSB
CHARGING
BATTERY
CHARGER
SOFT-START
144mA
VSYS
VUSB
IUSB
IBAT
3.5V
3.75V
475mA
-330mA
Typical Operating Characteristics (continued)(TA = +25°C, unless otherwise noted.)
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
Typical Operating Characteristics (continued)(TA = +25°C, unless otherwise noted.)
100µs/div
USB DISCONNECT WITH NO DC
(RSYS = 25Ω)2V/div
MAX8903A toc26
5V/div
500mA/div
500mA/div
3.6V
475mA
VSYS
VUSB
IUSB
IBAT
144mA-330mA
200µs/div
USB SUSPEND5V/div
MAX8903A toc27
500mA/div
2V/div
500mA/div
475mA
-475mA
VUSUS
IUSB
VSYS
IBAT0V
3.7V
200µs/div
USB RESUME5V/div
MAX8903A toc28
500mA/div
2V/div
500mA/div
475mA
-475mA0V
3.6V
3.6V3.8V
BATTERY
CHARGER
SOFT-START
CUSB
CHARGING
VUSUS
IUSB
VSYS
IBAT
Pin Description
PINNAMEFUNCTION1, 2PGPower Ground for Step-Down Low-Side Synchronous n-Channel MOSFET. Both PG pins must be
connected together externally.
3, 4DC
DC Power Input. DC is capable of delivering up to 2A to SYS. DC supports both AC adapter and USB
inputs. The DC current limit is set through DCM, IUSB, or IDC depending on the input source used. See
Table 2. Both DC pins must be connected together externally. Connect at least a 4.7µF ceramic capacitor
from DC to PG.DCM
Current-Limit Mode Setting for the DC Power Input. When logic-high, the DC input current limit is set by
the resistance from IDC to GND. When logic-low, the DC input current limit is internally programmed to
500mA or 100mA, as set by the IUSB logic input. There is an internal diode from DCM (anode) to DC
(cathode) as shown in Figure 1.BSTHigh-Side MOSFET Driver Supply. Bypass BST to LX with a 0.1µF ceramic capacitor.IUSBUSB Current-Limit Set Input. Drive IUSB logic-low to set the USB current limit to 100mA. Drive IUSB logic-
high to set the USB current limit to 500mA.DOKDC Power-OK Output. Active-low open-drain output pulls low when a valid input is detected at DC. DOK
is still valid when the charger is disabled (CEN high).
9VLLogic LDO Output. VL is the output of an LDO that powers the MAX8903_ internal circuitry and charges
the BST capacitor. Connect a 1µF ceramic capacitor from VL to GND.CTCharge Timer Set Input. A capacitor (CCT) from CT to GND sets the fast-charge and prequal fault timers.
Connect to GND to disable the timer.IDCDC Current-Limit Set Input. Connect a resistor (RIDC) from IDC to GND to program the current limit of the
step-down regulator from 0.5A to 2A when DCM is logic-high.GNDGround. GND is the low-noise ground connection for the internal circuitry.
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
Pin Description (continued)
PINNAMEFUNCTIONISETCharge Current Set Input. A resistor (RISET) from ISET to GND programs the fast-charge current up to 2A.
The prequal charge current is 10% of the fast-charge current.CENCharger Enable Input. Connect CEN to GND to enable battery charging when a valid source is connected
at DC or USB. Connect to VL, or drive high to disable battery charging.USUSUSB Suspend Input. Drive USUS logic-high to enter USB suspend mode, lowering USB current to 115µA,
and internally shorting SYS to BAT.THM
Thermistor Input. Connect a negative temperature coefficient (NTC) thermistor from THM to GND.
Connect a resistor equal to the thermistor +25°C resistance from THM to VL. Charging is suspended
when the thermistor is outside the hot and cold limits. Connect THM to GND to disable the thermistor
temperature sensor.USBUSB Power Input. USB is capable of delivering 100mA or 500mA to SYS as set by the IUSB logic input.
Connect a 4.7µF ceramic capacitor from USB to GND.FLTFault Output. Active-low, open-drain output pulls low when the battery timer expires before prequal or
fast-charge completes.UOKUSB Power-OK Output. Active-low, open-drain output pulls low when a valid input is detected at USB.
UOK is still valid when the charger is disabled (CEN high).
20, 21BAT
Battery Connection. Connect to a single-cell Li+ battery. The battery charges from SYS when a valid
source is present at DC or USB. BAT powers SYS when neither DC nor USB power is present, or when the
SYS load exceeds the input current limit. Both BAT pins must be connected together externally.CHGCharger Status Output. Active-low, open-drain output pulls low when the battery is in fast-charge or
prequal. Otherwise, CHG is high impedance.
23, 24SYS
System Supply Output. SYS connects to BAT through an internal 50mΩ system load switch when DC or
USB are invalid, or when the SYS load is greater than the input current limit.
When a valid voltage is present at DC or USB, SYS is limited to VSYSREG. When the system load (ISYS)
exceeds the DC or USB current limit, SYS is regulated to 50mV below BAT, and both the powered input
and the battery service SYS.
Bypass SYS to GND with an X5R or X7R ceramic capacitor. See Table 6 for the minimum recommended
SYS capacitor (CSYS). Both SYS pins must be connected together externally.
25, 26CS
70mΩ Current-Sense Input. Connect the step-down inductor from LX to CS. When the step-down
regulator is on, there is a 70mΩ current-sense MOSFET from CS to SYS. When the step-down regulator is
off, the internal CS MOSFET turns off to block current from SYS back to DC.
27, 28LXInductor Connection. Connect the inductor between LX and CS. Both LX pins must be connected together
externally.
—EPExposed Pad. Connect the exposed pad to GND. Connecting the exposed pad does not remove the
requirement for proper ground connections to the appropriate pins.
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter PowerSYS
BATTERY
CONNECTOR
BAT+
BAT-
NTC
THM
USB
BAT
ISETLi+ BATTERY
CHARGER
AND SYS LOAD SWITCH
THERMAL
REGULATION
CHARGER
CURRENT-
VOLTAGE
CONTROL
USB
UOK
DOK
DC POWER
MANAGEMENT
PWM
STEP-DOWN
REGULATOR
PWR
USB POWER
MANAGEMENT
CURRENT-
LIMITED
VOLTAGE
REGULATOR
SET
INPUT
LIMIT
PWRVL
CHG
FLT
CHARGE
TERMINATION
AND MONITOR
CHARGE
TIMER
THERMISTOR
MONITOR
(SEE FIGURE 7)
CEN
INPUT AND
CHARGER
CURRENT-LIMIT
SET LOGIC
DCM
IUSB
USUS
IDC
500mA
100mA
USB
LIMIT
LIMIT
ADAPTER
GND
DC MODE
USB
SUSPEND
SYSTEM
LOADCSBST
SET
INPUT
LIMIT
MAX8903_
Figure 1. Functional Block Diagram
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter Power
Circuit DescriptionThe MAX8903_ is a dual input charger with a 16V input
for a wide range of DC sources and USB inputs. The IC
includes a high-voltage (16V) input DC-DC step-down
converter that reduces charger power dissipation while
also supplying power to the system load. The step-
down converter supplies up to 2A to the system, the
battery, or a combination of both.
A USB charge input can charge the battery and power
the system from a USB power source. When powered
from USB or the DC input, system load current peaks
that exceed what can be supplied by the input are sup-
plemented by the battery.
The MAX8903_ also manages load switching from the
battery to and from an external power source with an
on-chip 50mΩMOSFET. This switch also helps support
load peaks using battery power when the input source
BSTSYS
SYS
BAT
BAT
FLT
UOK
DOK
FAULT
OUTPUT
USB PWR OK
DC PWR OK
TO VL
RPU
4 x 100kΩUSB
ISET
IDC
RISET
RIDC
DCM
THM
CEN
IUSB
GND
NTC
10kΩUSUS
CHARGE ON
OFF
100mA
500mA
USB SUSPEND
TO SYSTEM
LOAD
CHG22CHARGE
INDICATOR
CDC
4.7µFCCT
0.15µF
ADAPTER
VBUS
GND
CBST
0.1µF
1µH
CUSB
4.7µF
USB
(SEE TABLE 5 FOR
INDUCTOR SELECTION)
10kΩ
TO DC
1-CELL
LI+
CBAT
10µF
CVL
1µF
CSYS
(SEE TABLE 6 FOR CSYS SELECTION)
MAX8903_
Figure 2. Typical Application Circuit Using a Separate DC and USB Connector
MAX8903A–E/G/H/J/N/Y
2A 1-Cell Li+ DC-DC Chargers
for USB and Adapter PowerAs shown in Figure 1, the IC includes a full-featured
charger with thermistor monitor, fault timer, charger
status, and fault outputs. Also included are power-OK
signals for both USB and DC. Flexibility is maintained
with adjustable charge current, input current limit, and
a minimum system voltage (when charging is scaled
back to hold the system voltage up).
The MAX8903_ prevents overheating during high ambi-
ent temperatures by limiting charging current when the
die temperature exceeds +100°C.
DC Input—Fast Hysteretic
Step-Down RegulatorIf a valid DC input is present, the USB power path is
turned off and power for SYS and battery charging is
supplied by the high-frequency step-down regulator
from DC. If the battery voltage is above the minimum
system voltage (VSYSMIN, Figure 4), the battery charger
connects the system voltage to the battery for lowest
power dissipation. The step-down regulation point is
then controlled by three feedback signals: maximum
step-down output current programmed at IDC, maximum
BSTSYS
SYS
BAT
BAT
FLT
UOK
DOK
FAULT
OUTPUT
USB PWR-OK
DC PWR-OK
TO VL
RPU
4 x 100kΩUSB
ISET
IDC
RISET
RIDC
DCM
THM
CEN
IUSB
GND
NTC
10kΩUSUS
CHARGE ON
OFF
100mA
500mA
USB SUSPEND
TO SYSTEM
LOAD
CHG22CHARGE
INDICATOR
CDC
4.7µF
1µHCCT
0.15µF
CBST
0.1µF13
10kΩ
1-CELL
LI+
CBAT
10µF
CSYS
(SEE TABLE 6 FOR CSYS SELECTION)
MAX8903_
VBUS
GND
CVL
1µF
USB
ADAPTERDC MODE
499kΩ(SEE TABLE 5 FOR
INDUCTOR VALUE
SELECTION)
Figure 3. Typical Application Circuit Using a Mini 5 Style Connector or Other DC/USB Common Connector
