MAX8744ETJ+T ,High-Efficiency, Quad Output, Main Power-Supply Controllers for Notebook ComputersApplications28 13 CSL5CSL3MAX874429 12Main Power Supplies CSH3 CSH5MAX8745FB3 30 11 FB52 to 4 Li+ C ..
MAX874CPA ,10レA, Low-Dropout, Precision Voltage ReferencesFeaturesThe MAX872/MAX874 precision 2.5V and 4.096V micro- ' Output Voltagepower voltage references ..
MAX874CSA ,10レA, Low-Dropout, Precision Voltage ReferencesELECTRICAL CHARACTERISTICS—MAX874(V = 4.3V, I = 0mA, T = +25°C, unless otherwise noted.)L AINPARAME ..
MAX874CSA ,10レA, Low-Dropout, Precision Voltage ReferencesELECTRICAL CHARACTERISTICS—MAX874(V = 4.3V, I = 0mA, T = +25°C, unless otherwise noted.)L AINPARAME ..
MAX874CSA ,10レA, Low-Dropout, Precision Voltage ReferencesApplicationsHand-Held Instruments Ordering InformationBattery-Operated EquipmentPART TEMP. RANGE PI ..
MAX874CSA ,10レA, Low-Dropout, Precision Voltage ReferencesMAX872/MAX87419-0005; Rev 2; 6/9710µA, Low-Dropout,Precision Voltage References
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
MB84VD22193EE-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 ..
MB84VD22193EE-90PBS ,32M (x 8/x16) FLASH MEMORY & 4M (x 8/x16) STATIC RAMFUJITSU SEMICONDUCTORDS05-50204-2EDATA SHEETStacked MCP (Multi-Chip Package) FLASH MEMORY & SRAMCMO ..
MB84VD22194EE-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 ..
MB84VD22387EJ-90 , 32M (X16) FLASH MEMORY 16M (X16) SRAM Interface FCRAM
MAX8744ETJ+-MAX8744ETJ+T
High-Efficiency, Quad Output, Main Power-Supply Controllers for Notebook Computers
General DescriptionThe MAX8744/MAX8745 are dual step-down, switch-
mode, power-supply (SMPS) controllers with synchro-
nous rectification, intended for main 5V/3.3V power
generation in battery-powered systems. Fixed-frequen-
cy operation with optimal interleaving minimizes input
ripple current from the lowest input voltages up to the
26V maximum input. Optimal 40/60 interleaving allows
the input voltage to go down to 8.3V before duty-cycle
overlap occurs, compared to 180°out-of-phase regula-
tors where the duty-cycle overlap occurs when the
input drops below 10V.
Output current sensing provides peak current-limit pro-
tection, using either an accurate sense resistor or using
lossless inductor DCR current sensing. A low-noise
mode maintains high light-load efficiency while keeping
the switching frequency out of the audible range.
An internal, fixed 5V, 100mA linear regulator powers up
the MAX8744/MAX8745 and their gate drivers, as well
as external keep-alive loads. When the main PWM reg-
ulator is in regulation, an automatic bootstrap switch
bypasses the internal linear regulator, providing current
up to 200mA. An additional adjustable linear-regulator
driver with an external pnp transistor may be used with
a secondary winding to provide a 12V supply, or pow-
ered directly from the main outputs to generate low-
voltage outputs as low as 1V.
Independent enable controls and power-good signals
allow flexible power sequencing. Voltage soft-start
gradually ramps up the output voltage and reduces
inrush current, while soft-shutdown gradually ramps the
output voltage down, preventing negative voltage dips.
The MAX8744/MAX8745 feature output undervoltage
and thermal-fault protection. The MAX8744 also
includes output overvoltage-fault protection.
The MAX8744/MAX8745 are available in a 32-pin, 5mm
x 5mm, thin QFN package. The exposed backside pad
improves thermal characteristics for demanding linear
keep-alive applications.
ApplicationsMain Power Supplies
2 to 4 Li+ Cell Battery-Powered Devices
Notebook and Subnotebook Computers
PDAs and Mobile Communicators
FeaturesFixed-Frequency, Current-Mode Control40/60 Optimal InterleavingInternal BST SwitchesInternal 5V, 100mA Linear RegulatorAuxiliary Linear-Regulator Driver (12V or
Adjustable Down to 1V)Dual Mode™Feedback—3.3V/5V Fixed or
Adjustable Output Voltages200kHz/300kHz/500kHz Switching FrequencyUndervoltage and Thermal-Fault ProtectionOvervoltage-Fault Protection (MAX8744 Only)6V to 26V Input Range2V ±0.75% Reference OutputIndependent Enable Inputs and Power-Good
OutputsSoft-Start and Soft-Shutdown (Voltage Ramp)8µA (typ) Shutdown Current
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers19-3796; Rev 0; 4/06
+Denotes lead-free package.
MAX8744
MAX8745
THIN QFN5mm x 5mmTOP VIEW
DRVASHDN
ON3ON5
REF
ONA
DL3INLDO5LX3PGNDDL5
CSL3672422201918
CSH3
FB3
PGOOD5
CSL5
CSH5
FB5
ILIM
PGOODA10FBASKIP9OUTAFSEL
PGOOD315BST5BST316DH5
GND
LX5
DH3
Pin Configuration
Ordering Information
PARTTEMP RANGEPIN-
PACKAGE
PKG
CODE
MAX8744ETJ+-40°C to +85°C32 Thin QFN
(5mm x 5mm)T3255-4
MAX8745ETJ+-40°C to +85°C32 Thin QFN
(5mm x 5mm)T3255-4
Dual Mode is a trademark of Maxim Integrated Products, Inc.
EVALUATION KIT
AVAILABLE
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
ABSOLUTE MAXIMUM RATINGSStresses 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.
IN, SHDN, DRVA, OUTA to GND............................-0.3V to +28V
LDO5, ON3, ON5, ONA to GND ..............................-0.3V to +6V
PGOODA, PGOOD3, PGOOD5 to GND...................-0.3V to +6V
CSL3, CSH3, CSL5, CSH5 to GND..........................-0.3V to +6V
REF, FB3, FB5, FBA to GND...................-0.3V to (VLDO5+ 0.3V)
SKIP, FSEL, ILIM to GND........................-0.3V to (VLDO5+ 0.3V)
DL3, DL5 to PGND..................................-0.3V to (VLDO5+ 0.3V)
BST3, BST5 to PGND.............................................-0.3V to +34V
BST3 to LX3..............................................................-0.3V to +6V
DH3 to LX3..............................................-0.3V to (VBST3+ 0.3V)
BST5 to LX5..............................................................-0.3V to +6V
DH5 to LX5..............................................-0.3V to (VBST5+ 0.3V)
GND to PGND.......................................................-0.3V to +0.3V
BST3, BST5 LDO5.................................................-0.3V to +0.3V
LDO Short Circuit to GND..........................................Momentary
REF Short Circuit to GND...........................................Momentary
DRVA Current (Sinking)......................................................30mA
OUTA Shunt Current...........................................................30mA
Continuous Power Dissipation (TA= +70°C)
Multilayer PCB
32-Pin, 5mm x 5mm TQFN
(derated 34.5mW/°C above +70°C) .........................2459mW
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
ELECTRICAL CHARACTERISTICS(Circuit of Figure 1, VIN= 12V, both SMPS enabled, FSEL = REF, SKIP= GND, ILIM = LDO5, FBA = LDO5, IREF= ILDO5= IOUTA=
no load, TA
= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
INPUT SUPPLIES (Note 1)LDO5 in regulation5.426.0VIN Input Voltage RangeVININ = LDO5, VCSL5 < 4.4V4.55.5V
VIN Operating Supply CurrentIINLDO5 switched over to CSL5, either
SMPS on2036µA
VIN Standby Supply CurrentIIN(STBY)VIN = 6V to 26V, both SMPS off, includes
ISHDN65120µA
VIN Shutdown Supply CurrentIIN(SHDN)VIN = 6V to 26V820µA
Quiescent Power ConsumptionPQ
Both S M P S on, FB3 = FB5 = LD O5,
SKIP = GN D , V C S L 3 = 3.5V , V C S L 5 = 5.3V ,OU T A = 15V ,IN + P C S L 3 + P C S L 5 + P OU T A
3.54.5mW
MAIN SMPS CONTROLLERS3.3V Output Voltage in Fixed
ModeVOUT3VIN = 6V to 26V, SKIP = FB3 = LDO5,
0 < VCSH3 - VCSL3 < 50mV (Note 2)3.2653.3153.365V
5V Output Voltage in Fixed ModeVOUT5VIN = 6V to 26V, SKIP = FB5 = LDO5,
0 < VCSH5 - VCSL5 < 50mV (Note 2)4.945.0155.09V
VIN = 6V to 26V, FB3 or FB5
duty factor = 20% to 80%1.9802.0102.040
Feedback Voltage in Adjustable
Mode (Note 2)VFB_
VIN = 6V to 26V, FB3 or FB5
duty factor = 50%1.9902.0102.030
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
ELECTRICAL CHARACTERISTICS (continued)(Circuit of Figure 1, VIN= 12V, both SMPS enabled, FSEL = REF, SKIP= GND, ILIM = LDO5, FBA = LDO5, IREF= ILDO5= IOUTA=
no load, TA
= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSOutput Voltage Adjust RangeEither SMPS2.05.5V
FB3, FB5 Dual Mode Threshold3.0VLOO5
- 1.0
VLOO5
- 0.4V
Feedback Input Leakage CurrentVFB3 = VFB5 = 2.1V-0.1+0.1µA
DC Load RegulationEither SMPS, SKIP = LDO5,
0 < VCSH_ - VCSL_ < 50mV-0.1%
Line Regulation ErrorEither SMPS, 6V < VIN < 26V0.03%/V
FSEL = GND170200230
FSEL = REF270300330Operating Frequency (Note 1)fOSC
FSEL = LDO5425500575
kHz
Maximum Duty FactorDMAX(Note 1)97.599%
Minimum On-TimetONMIN100ns%SMPS3-to-SMPS5 Phase ShiftSMPS5 starts after SMPS3144Deg
CURRENT LIMITILIM Adjustment Range0.5VREFV
Current-Sense Input Leakage
CurrentCSH3 = CSH5 = GND or LDO5-1+1µA
Current-Limit Threshold (Fixed)VLIMITVCSH_ - VCSL _, ILIM = LDO5455055mV
VILIM = 2.00V185200215Current-Limit Threshold
(Adjustable)VLIMITVCSH_ - VCSL _VILIM = 1.00V94100106mV
VCSH_ - VCSL _, SKIP = ILIM = LDO5-67-60-53mV
Current-Limit Threshold
(Negative)VNEGVCSH_ - VCSL _, SKIP = LDO5, adjustable
mode, percent of current limit-120%
Current-Limit Threshold
(Zero Crossing)VZXVCSH_ - VCSL _, SKIP = GND,
ILIM = LDO5036mV
ILIM = LDO561014mV
Idle Mode™ ThresholdVIDLEVCSH_ - VCSL _,
SKIP = GND
With respect to
current-limit
threshold (VLIMIT)%
ILIM = LDO52.557.5mV
Idle Mode Threshold
(Low Audible-Noise Mode)VIDLEVCSH_ - VCSL _,
SKIP = REF
With respect to
current-limit
threshold (VLIMIT)%
ILIM Leakage CurrentILIM = GND or REF-1+1µA
Idle Mode is a trademark of Maxim Integrated Products, Inc.
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
ELECTRICAL CHARACTERISTICS (continued)(Circuit of Figure 1, VIN= 12V, both SMPS enabled, FSEL = REF, SKIP= GND, ILIM = LDO5, FBA = LDO5, IREF= ILDO5= IOUTA=
no load, TA
= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSSoft-Start Ramp TimetSSTARTMeasured from the rising edge of ON_ to
full scale2ms
Soft-Stop Ramp TimetSSTOPMeasured from the falling edge of ON_ to
full scale4ms
INTERNAL FIXED LINEAR REGULATORSLDO5 Output VoltageVLDO5ON5 = GND, 6V < VIN < 26V,
0 < ILDO5 < 100mA4.854.955.10V
LDO5 Undervoltage-Lockout Fault
ThresholdRising edge, hysteresis = 1% ( typ ) 225450mA
LDO5 Bootstrap Switch ThresholdRi si ng ed g e of C S L5, hyster esi s = 1% ( typ ) 4.354.554.70V
LD O 5 Bootstr ap S w i tch Resi stanceLD O 5 to C S L5, V C S L 5 = 5V , IL D O5 = 50m A15Ω
Short-Circuit CurrentLDO5 = GND, ON5 = GND225450mA
Short-Circuit Current (Switched
Over to CSL_)LDO5 = GND, VCSL5 > 4.7V200425mA
AUXILIARY LINEAR REGULATORDRVA Voltage RangeVDRVA0.526.0V
VFBA = 1.05V, VDRVA = 5V0.4DRVA Drive CurrentVFBA = 0.965V, VDRVA = 5V10mA
FBA Regulation ThresholdVFBAVDRVA = 5V, IDRVA = 1mA (sink)0.981.001.02V
FBA Load RegulationVDRA = 5V, IDRVA = 0.5mA to 5mA-1.2-2.2%
OUTA Shunt Trip LevelRising edge252627V
FBA Leakage CurrentVFBA = 1.035V-0.1+0.1µA
Secondary Feedback Regulation
ThresholdVDRVA - VOUTA0V
DL5 Pulse Width1/
3fOSCµs
OUTA Leakage CurrentIOUTAVDRVA = VOUTA = 25V50µA
REFERENCE (REF)Reference VoltageVREFLDO5 in regulation, IREF = 01.9852.002.015V
Reference Load-Regulation ErrorΔVREFIREF = -5µA to +50µA-10+10mV
REF Lockout VoltageVREF(UVLO)Rising edge, hysteresis = 100mV (typ)1.90V
FAULT DETECTIONOutput Overvoltage Trip
Threshold (MAX8744 Only)
With respect to error-comparator
threshold81114%
Outp ut Over vol tag e Faul tr op ag ati on D el ay ( M AX 8744 Onl y) tOVP50mV overdrive10µs
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
ELECTRICAL CHARACTERISTICS (continued)(Circuit of Figure 1, VIN= 12V, both SMPS enabled, FSEL = REF, SKIP= GND, ILIM = LDO5, FBA = LDO5, IREF= ILDO5= IOUTA=
no load, TA
= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSOutput Undervoltage Protection
Trip Threshold
With respect to error-comparator
threshold657075%
Output Undevoltage Fault
Propagation DelaytUVP50mV overdrive10µs
Output Undervoltage Protection
Blanking TimetBLANKFrom rising edge of ON_ with respect to
fSW5000614470001/fOSC
PGOOD_ Lower Trip ThresholdWith respect to error-comparator
threshold, hysteresis = 1% (typ)-12-10-8%
Falling edge, 50mV overdrive10PGOOD_ Propagation DelaytPGOOD_Rising edge, 50mV overdrive1µs
PGOOD_ Output Low VoltageISINK = 1mA0.4V
PGOOD_ Leakage CurrentIPGOOD_High state, PGOOD_ forced to 5.5V1µA
Thermal-Shutdown ThresholdtSHDNHysteresis = 15°C+160°C
GATE DRIVERSDH_ Gate-Driver On-ResistanceRDHBST_ – LX_ forced to 5V1.35Ω
DL_, high state1.75DL_ Gate-Driver On-ResistanceRDLDL_, low state0.63Ω
DH_ Gate-Driver Source/Sink
CurrentIDHDH_ forced to 2.5V, BST_ - LX_ forced to2A
DL_ Gate-Driver Source CurrentIDL (SOURCE)DL_ forced to 2.5V1.7A
DL_ Gate-Driver Sink CurrentIDL (SINK)DL_ forced to 2.5V3.3A
DH_low to DL_high1545Dead TimetDEADDL_low to DH_high1544ns
Internal BST_ Switch On-
ResistanceRBSTIBST = 10mA5Ω
BST_ Leakage CurrentVBST_ = 26V220µA
INPUTS AND OUTPUTSRising trip level1.11.62.2SHDN Input Trip LevelFalling trip level0.9611.04V
High2.4ONA Logic Input VoltageHysteresis = 600mV (typ)Low0.8V
SMPS off level/clear fault level0.8
Delay start level1.92.1ON3, ON5 Input Voltage
SMPS on level2.4
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
ELECTRICAL CHARACTERISTICS(Circuit of Figure 1, VIN= 12V, both SMPS enabled, FSEL = REF, SKIP= GND, ILIM = LDO5, FBA = LDO5, IREF= ILDO5= IOUTA=
no load, TA
= -40°C to +85°C, unless otherwise noted.) (Note 3)
PARAMETERSYMBOLCONDITIONSMINMAXUNITS
INPUT SUPPLIES (Note 1) LDO5 in regulation 5.4 26.0 VIN Input Voltage Range VIN IN = LDO5, VCSL5 < 4.4V 4.5 5.5 V
VIN Operating Supply Current IIN LDO5 switched over to CSL5, either SMPS on 40 μA
VIN Standby Supply Current IIN(STBY) VIN = 6V to 26V, both SMPS off, includes
ISHDN 120 μA
VIN Shutdown Supply Current IIN(SHDN) VIN = 6V to 26V 20 μA
Quiescent Power Consumption PQ
Both SMPS on, FB3 = FB5 = LDO5; SKIP =
GND, VCSL3 = 3.5V, VCSL5 = 5.3V,
VOUTA = 15V,
PIN + PCSL3 + PCSL5 4.5 mW
MAIN SMPS CONTROLLERS 3.3V Output Voltage in Fixed
Mode VOUT3 VIN = 6V to 26V, SKIP = FB3 = LDO5,
0 < VCSH3 - VCSL3 < 50mV (Note 2) 3.255 3.375 V
5V Output Voltage in Fixed Mode VOUT5 VIN = 6V to 26V, SKIP = FB5 = LDO5,
0 < VCSH5 - VCSL5 < 50mV (Note 2) 4.925 5.105 V
Feedback Voltage in Adjustable
Mode VFB_ VIN = 6V to 26V, FB3 or FB5
duty factor = 20% to 80% (Note 2) 1.974 2.046 V
Output Voltage Adjust Range Either SMPS 2.0 5.5 V
FB3, FB5 Dual Mode Threshold 3V VLDO5 -
0.4 V
FSEL = GND 170
230
FSEL = REF 270
330 Operating Frequency (Note 1) fOSC
FSEL = LDO5 425
575
kHz
Maximum Duty Factor DMAX 97 %
ELECTRICAL CHARACTERISTICS (continued)(Circuit of Figure 1, VIN= 12V, both SMPS enabled, FSEL = REF, SKIP= GND, ILIM = LDO5, FBA = LDO5, IREF= ILDO5= IOUTA=
no load, TA
= 0°C to +85°C, unless otherwise noted. Typical values are at TA= +25°C.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSHighVLDO5
- 0.4
REF1.652.35Tri-Level Input LogicSKIP, FSEL
GND0.5
SKIP, FSEL forced to GND or LDO5-1+1Input Leakage CurrentSHDN forced to GND or 26V-1+1µA
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
ELECTRICAL CHARACTERISTICS (continued)(Circuit of Figure 1, VIN= 12V, both SMPS enabled, FSEL = REF, SKIP= GND, ILIM = LDO5, FBA = LDO5, IREF= ILDO5= IOUTA=
no load, TA
= -40°C to +85°C, unless otherwise noted.) (Note 3)
PARAMETERSYMBOLCONDITIONSMINMAXUNITS
CURRENT LIMIT ILIM Adjustment Range 0.5 VREF V
Current-Limit Threshold (Fixed) VLIMIT VCSH_ - VCSL _, ILIM = LDO5 44 56 mV
VILIM = 2.00V 185 215 Current-Limit Threshold
(Adjustable) VLIMIT VCSH_ - VCSL _
VILIM = 1.00V 93 107
mV
INTERNAL FIXED LINEAR REGULATORS LDO5 Output Voltage VLDO5 ON5 = GND, 6V < VIN < 26V,
0 < ILDO5 < 100mA 4.85 5.10 V
LDO5 Undervoltage-Lockout
Fault Threshold Rising edge, hysteresis = 1% (typ) 3.7 4.1 V
LDO5 Bootstrap Switch Rising edge of CSL5, hysteresis = 1% (typ) 4.30 4.75 V
Short-Circuit Current LDO5 = GND, ON5 = GND 450 mA
Short-Circuit Current (Switched
over to CSL_) LDO5 = GND, VCSL5 > 4.7V 200 mA
AUXILIARY LINEAR REGULATOR DRVA Voltage Range VDRVA 0.5 26 V
VFBA = 1.05V, VDRVA = 5V 0.4 DRVA Drive Current VFBA = 0.965V, VDRVA = 5V 10 mA
FBA Regulation Threshold VFBA VDRVA = 5V, IDRVA = 1mA (sink) 0.98 1.02 V
OUTA Shunt Trip Level 25 27 V
REFERENCE (REF) Reference Voltage VREF LDO5 in regulation, IREF = 0 1.980 2.020 V
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
ELECTRICAL CHARACTERISTICS (continued)(Circuit of Figure 1, VIN= 12V, both SMPS enabled, FSEL = REF, SKIP= GND, ILIM = LDO5, FBA = LDO5, IREF= ILDO5= IOUTA=
no load, TA
= -40°C to +85°C, unless otherwise noted.) (Note 3)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS
FAULT DETECTIONOutput Overvoltage Trip
Threshold (MAX8744 Only)With respect to error comparator threshold814%
Output Undervoltage ProtectionWith respect to error comparator threshold6575%
PGOOD_ Lower Trip ThresholdWith respect to error comparator threshold,
hysteresis = 1%-12-8%
PGOOD_ Output Low VoltageISINK = 1mA0.4V
GATE DRIVERSDH_ Gate-Driver On-ResistanceRDHBST_ – LX_ forced to 5V5Ω
DL_, high state5DL_ Gate-Driver On-ResistanceRDLDL_, low state3Ω
INPUTS AND OUTPUTSRising trip level1.02.3SHDN Input Trip LevelFalling trip level0.961.04V
High2.4ONA Logic Input VoltageHysteresis = 600mVLow0.8V
SMPS off level/clear fault level0.8
Delay start level1.92.1ON3, ON5 Input Voltage
SMPS on level2.4
HighVLDO5 - 0.4
REF1.652.35Tri-Level Input LogicSKIP, FSEL
GND0.5
Note 1:The MAX8744/MAX8745 cannot operate over all combinations of frequency, input voltage (VIN), and output voltage. For
large input-to-output differentials and high switching-frequency settings, the required on-time may be too short to maintain
the regulation specifications. Under these conditions, a lower operating frequency must be selected. The minimum on-time
must be greater than 150ns, regardless of the selected switching frequency. On-time and off-time specifications are mea-
sured from 50% point to 50% point at the DH_ pin with LX_ = GND, VBST_= 5V, and a 250pF capacitor connected from
DH_ to LX_. Actual in-circuit times may differ due to MOSFET switching speeds.
Note 2:When the inductor is in continuous conduction, the output voltage has a DC-regulation level lower than the error-comparator
threshold by 50% of the ripple. In discontinuous conduction (SKIP= GND, light load), the output voltage has a DC regula-
tion level higher than the trip level by approximately 1% due to slope compensation.
Note 3:Specifications from -40°C to +85°C are guaranteed by design, not production tested.
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
OUTPUT VOLTAGE DEVIATION
vs. INPUT VOLTAGEINPUT VOLTAGE (V)
OUTPUT VOLTAGE DEVIATION (%)
MAX8744 toc0748121620
3.3V OUTPUT
5.0V OUTPUT
5V OUTPUT EFFICIENCY
vs. LOAD CURRENTLOAD CURRENT (A)
EFFICIENCY (%)
MAX8744 toc01
20V
SKIP MODE
PWM MODE
12V
5V OUTPUT EFFICIENCY
vs. LOAD CURRENTLOAD CURRENT (A)
EFFICIENCY (%)
MAX8744 toc02
PWM MODELOW-NOISE
MODE
SKIP MODE
5V OUTPUT VOLTAGE
vs. LOAD CURRENTLOAD CURRENT (A)
OUTPUT VOLTAGE (V)
MAX8744 toc03
SKIP MODE
LOW-NOISE MODE
PWM MODE
3.3V OUTPUT EFFICIENCY
vs. LOAD CURRENTLOAD CURRENT (A)
EFFICIENCY (%)
MAX8744 toc04
20V
SKIP MODE
PWM MODE
12V
3.3V OUTPUT EFFICIENCY
vs. LOAD CURRENTLOAD CURRENT (A)
EFFICIENCY (%)
MAX8744 toc05
LOW-NOISE
MODE
SKIP MODE
PWM MODE
3.3V OUTPUT VOLTAGE
vs. LOAD CURRENTLOAD CURRENT (A)
OUTPUT VOLTAGE (V)
MAX8744 toc06
PWM MODE
SKIP MODE
LOW-NOISE MODE
NO-LOAD INPUT SUPPLY CURRENT
vs. INPUT VOLTAGE INPUT VOLTAGE (V)
SUPPLY CURRENT (mA)
MAX8744 toc0848121620
PWM MODE
SKIP MODE
LOW-NOISE MODE
STANDBY AND SHUTDOWN INPUT CURRENT
vs. INPUT VOLTAGE INPUT VOLTAGE (V)
SUPPLY CURRENT (
MAX8744 toc0948121620
STANDBY (ONx = GND)
SHUTDOWN
(SHDN = GND)
Typical Operating Characteristics(Circuit of Figure 1, VIN= 12V, SKIP= GND, FSEL = REF, TA= +25°C, unless otherwise noted.)
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
3.3V IDLE MODE CURRENT
vs. INPUT VOLTAGEINPUT VOLTAGE (V)
IDLE-MODE CURRENT (A)
MAX8744 toc1048121620
SKIP MODE
SKIP = GND
LOW-NOISE MODE
SKIP = REF
3.3V SWITCHING FREQUENCY
vs. LOAD CURRENTMAX8744 toc11
LOAD CURRENT (A)
SWITCHING FREQUENCY (kHz)0.10.01
FORCED-PWM
LOW-NOISE SKIP
PULSE SKIPPING
REFERENCE OFFSET VOLTAGE
DISTRIBUTION2V REF OFFSET VOLTAGE (mV)
SAMPLE PERCENTAGE (%)
MAX8744 toc12
+85°C
+25°C
SAMPLE SIZE = 125
LDO5 OUTPUT VOLTAGE
vs. LOAD CURRENTLOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
MAX8744 toc1320406080100
OUTA OUTPUT VOLTAGE
vs. LOAD CURRENT
LOAD CURRENT (mA)
OUTPUT VOLTAGE (V)
MAX8744 toc1450100150
LDO5 POWER-UP
MAX8744 toc15
1ms/div
12V
A. INPUT SUPPLY, 5V/div
B. REF, 2V/div
SHDN = IN
C. LDO5, 5V/div
D. PGOOD5, 5V/div
Typical Operating Characteristics (continued)(Circuit of Figure 1, VIN= 12V, SKIP= GND, FSEL = REF, TA= +25°C, unless otherwise noted.)
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computersypical Operating Characteristics (continued)(Circuit of Figure 1, VIN= 12V, SKIP= GND, FSEL = REF, TA= +25°C, unless otherwise noted.)
SOFT-START WAVEFORMMAX8744 toc16
400μs/div
3.3V
12V
A. ON3 AND ON5, 5V/div
B. 5V OUTPUT (VOUT5), 5V/div
C. PGOOD5, 5V/div
D. AUX LDO OUTPUT
(VOUTA), 10V/div
E. L5 INDUCTOR CURRENT,
5A/div
SMPS DELAYED STARTUP SEQUENCE
(ON3 = REF)MAX8744 toc17
1ms/div
3.3V
3.3V
A. ON5, 5V/div
B. 5V OUTPUT (VOUT5), 5V/div
C. PGOOD5, 5V/div
ON3 = REF
D. 3.3V OUTPUT (VOUT3),
5V/div
E. PGOOD3, 5V/div
SMPS DELAYED STARTUP SEQUENCE
(ON5 = REF)MAX8744 toc18
1ms/div
3.3V
3.3V
A. ON3, 5V/div
B. 5V OUTPUT (VOUT5), 5V/div
C. PGOOD5, 5V/div
ON5 = REF
D. 3.3V OUTPUT (VOUT3),
5V/div
E. PGOOD3, 5V/div
SMPS SHUTDOWN WAVEFORMMAX8744 toc19
1ms/div
3.3V
3.3V
A. SHDN, 5V/div
B. 5V OUTPUT (VOUT5), 5V/div
C. PGOOD5, 5V/div
NO LOAD
D. 3.3V OUTPUT (VOUT3),
5V/div
E. PGOOD3, 5V/div
OUT5 LOAD TRANSIENTMAX8744 toc20
20μs/div
5.1V1A
12V
5.0V
4.9V
A. IOUT5 = 1A TO 5A, 5A/div
B. VOUT5, 50mV/div
C. INDUCTOR CURRENT,
5A/div
D. LX5, 10V/div
OUT3 LOAD TRANSIENTMAX8744 toc21
20μs/div
3.35V
12V
3.30V
3.25V
A. IOUT3 = 1A TO 3A, 5A/div
B. VOUT3, 50mV/div
C. INDUCTOR CURRENT,
5A/div
D. LX3, 10V/div
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
LDOH5 LOAD TRANSIENTMAX8744 toc25
20μs/div
5.00V
4.95V
100mA
A. LDO5 OUTPUT, 50mV/div
B. LOAD CURRENT, 50mA/div
MAX8744 toc22
40μs/div
3.3V
3.35V
12V
3.25V
A. SKIP, 5V/div
B. 3.3V OUTPUT (VOUT3),
100mV/div
0.5A LOAD
C. INDUCTOR CURRENT,
2A/div
D. LX3, 10V/div
SKIP TRANSITION
OUTPUT OVERVOLTAGE
FAULT PROTECTION (MAX8744 ONLY)MAX8744 toc23
1ms/div
A. PGOOD3, 5V/div
B. 3.3V OUTPUT (VOUT3),
2V/div
C. 5V OUTPUT (VOUT5),
5V/div
D. DL3, 5V/div
OUTPUT UNDERVOLTAGE
(SHORT-CIRCUIT) FAULT PROTECTIONMAX8744 toc24
20μs/div
3.3V
12V
A. LOAD FET GATE, 5V/div
B. 3.3V OUTPUT (VOUT3), 1V/div
30mΩ MOSFET
C. DL3, 5V/div
D. DH3, 10V/div
LDOHA LOAD TRANSIENTMAX8744 toc26
20μs/div
15.0V
14.5V
12.0V
11.9V
A. LOAD FET GATE, 5V/div
B. AUX LDO INPUT, 0.5V/div
0 TO 150mA LOAD TRANSIENT
C. AUX LDO OUTPUT (VOUTA),
0.1V/div
Typical Operating Characteristics (continued)(Circuit of Figure 1, VIN= 12V, SKIP= GND, FSEL = REF, TA= +25°C, unless otherwise noted.)
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
PINNAMEFUNCTIONONAAuxiliary LDO Enable Input. When ONA is pulled low, OUTA is high impedance and the secondary
feedback control is disabled. When ONA is driven high, the controller enables the auxiliary LDO.DRVAAuxiliary LDO Transistor Base Driver. Connect DRVA to the base of a pnp power transistor. Add a
680Ω pullup resistor between the base and emitter.ILIM
Peak Current-Limit Threshold Adjustment. The current-limit threshold defaults to 50mV if ILIM is pulled
up to LDO5. In adjustable mode, the current-limit threshold across CSH_ and CSL_ is precisely 1/10
the voltage seen at ILIM over a 0.5V to 2.0V range. The logic threshold for switchover to the 50mV
default value is approximately VLDO5 - 1V.SHDN
Shutdown Control Input. The device enters its 8µA supply-current shutdown mode if V SHDN is less
than the SHDN input falling edge trip level and does not restart until V SHDN is greater than the SHDN
input rising-edge trip level. Connect SHDN to VIN for automatic startup. SHDN can be connected to
VIN through a resistive voltage-divider to implement a programmable undervoltage lockout.ON3
3.3V SMPS Enable Input. Driving ON3 high enables the 3.3V SMPS, while pulling ON3 low disables
the 3.3V SMPS. If ON3 is connected to REF, the 3.3V SMPS starts after the 5V SMPS reaches
regulation (delayed start). Drive ON3 below the clear fault level to reset the fault latch.ON5
5V SMPS Enable Input. Driving ON5 high enables the 5V SMPS, while pulling ON5 low disables the
5V SMPS. If ON5 is connected to REF, the 5V SMPS starts after the 3.3V SMPS reaches regulation
(delayed start). Drive ON5 below the clear fault level to reset the fault latch.REF
2.0V Reference Voltage Output. Bypass REF to analog ground with a 0.1µF or greater ceramic
capacitor. The reference sources up to 50µA for external loads. Loading REF degrades output-
voltage accuracy according to the REF load-regulation error. The reference shuts down when the
system pulls SHDN low.GNDAnalog Ground. Connect the exposed backside pad to GND.FSEL
Frequency Select Input. This three-level logic input sets the controllers’ switching frequency. Connect
to LDO5, REF, or GND to select the following typical switching frequencies:
LDO5 = 500kHz, REF = 300kHz, GND = 200kHz.SKIP
Pulse-Skipping Control Input. Connect to LDO5 for low-noise, forced-PWM operation. Connect to REF
for automatic, low-noise, pulse-skipping operation at light loads. Connect to GND for automatic, high-
efficiency, pulse-skipping operation at light loads.FB5Feedback Input for the 5V SMPS. Connect to LDO5 for the preset 5V output. In adjustable mode, FB5
regulates to 2V.CSH5osi ti ve C ur r ent- S ense Inp ut for the 5V S M P S . C onnect to the p osi ti ve ter m i nal of the cur r ent- sense
el em ent. Fi g ur e 7 d escr i b es tw o d i ffer ent cur r ent- sensi ng op ti ons— usi ng accur ate sense r esi stor s or ossl ess i nd uctor D C R sensi ng .CSL5
Output-Sense and Negative Current-Sense Input for the 5V SMPS. When using the internal preset 5V
feedback-divider (FB5 = LDO5), the controller uses CSL5 to sense the output voltage. Connect to the
negative terminal of the current-sense element. CSL5 also serves as the bootstrap input for LDO5.PGOOD5
Open-Drain, Power-Good Output for the 5V SMPS. PGOOD5 is pulled low if CSL5 drops more than
10% (typ) below the normal regulation point. PGOOD5 is held low during soft-start and shutdown.
PGOOD5 becomes high impedance when CSL5 is in regulation.
Pin Description
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
PINNAMEFUNCTIONBST5
Boost Flying Capacitor Connection for the 5V SMPS. The MAX8744/MAX8745 include an internal
boost switch connected between LDO5 and BST5. Connect to an external capacitor as shown in
Figure 1.DH5High-Side Gate-Driver Output for the 5V SMPS. DH5 swings from LX5 to BST5.LX5Inductor Connection for the 5V SMPS. Connect LX5 to the switched side of the inductor. LX5 serves
as the lower supply rail for the DH5 high-side gate driver.DL5Low-Side Gate-Driver Output for the 5V SMPS. DL5 swings from PGND to LDO5.PGNDPower GroundLDO5
5V Internal Linear-Regulator Output. Bypass with 4.7µF minimum (1µF/25mA). Provides at least
100mA for the DL_ low-side gate drivers, the DH_ high-side drivers through the BST switches, the
PWM controller, logic, reference, and external loads. If CSL5 is greater than 4.5V and soft-start is
complete, the linear regulator shuts down, and LDO5 connects to CSL5 through a 1Ω switch rated for
loads up to 200mA.INInput of the Startup Circuitry and the LDO5 Internal 5V Linear Regulator. Bypass to PGND with a
0.22µF or greater ceramic capacitor close to the IC.PGOODA
Open-Drain, Power-Good Output for the Auxiliary LDO. PGOODA is pulled low if FBA drops more
than 10% (typ) below the normal regulation point, and when the auxiliary LDO is shut down. PGOODA
becomes high impedance when FBA is in regulation.DL3Low-Side Gate-Driver Output for the 3.3V SMPS. DL3 swings from PGND to LDO5.LX3Inductor Connection for the 3.3V SMPS. Connect LX3 to the switched side of the inductor. LX3 serves
as the lower supply rail for the DH3 high-side gate driver.DH3High-Side Gate-Driver Output for the 3.3V SMPS. DH3 swings from LX3 to BST3.BST3
Boost Flying Capacitor Connection for the 3.3V SMPS. The MAX8744/MAX8745 include an internal
boost switch connected between LDO5 and BST3. Connect to an external capacitor as shown in
Figure 1.PGOOD3
Open-Drain, Power-Good Output for the 3.3V SMPS. PGOOD3 is pulled low if CSL3 drops more than
10% (typ) below the normal regulation point. PGOOD3 is held low during soft-start and shutdown.
PGOOD3 becomes high impedance when CSL3 is in regulation.CSL3
Output Sense and Negative Current Sense for the 3.3V SMPS. When using the internal preset 3.3V
feedback divider (FB3 = LDO5), the controller uses CSL3 to sense the output voltage. Connect to the
negative terminal of the current-sense element.CSH3
Positive Current-Sense Input for the 3.3V SMPS. Connect to the positive terminal of the current-sense
element. Figure 7 describes two different current-sensing options—using accurate sense resistors or
lossless inductor DCR sensing.FB3Feedback Input for the 3.3V SMPS. Connect to LDO5 for fixed 3.3V output. In adjustable mode, FB3
regulates to 2V.
Pin Description (continued)
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
PINNAMEFUNCTIONFBAAuxiliary LDO Feedback Input. Connect a resistive voltage-divider from OUTA to analog ground to
adjust the auxiliary linear-regulator output voltage. FBA regulates at 1V.OUTA
Adjustable Auxiliary Linear-Regulator Output. Bypass OUTA to GND with 1µF or greater capacitor
(1µF/25mA). When DRVA < OUTA, the secondary feedback control triggers the DL5 for 1µs forcing
the controller to recharge the auxiliary storage capacitor. When DRVA exceeds 25V, the
MAX8744/MAX8745 enable a 10mA shunt on OUTA, preventing the storage capacitor from rising to
unsafe levels due to the transformer’s leakage inductance. Pulling ONA high enables the linear-
regulator driver and the secondary feedback control.EPExposed Pad. Connect the exposed backside pad to analog ground.
Pin Description (continued)
Table 1. Component Selection for Standard Applications
COMPONENT
300kHz
5V AT 5A
3.3V AT 6A
500kHz
5V AT 3A
3.3V AT 5A
INPUT VOLTAGEVIN = 7V TO 24VVIN = 7V TO 24VCIN_, Input Capacitor(3) 10µF, 25V
Taiyo Yuden TMK432BJ106KM
(3) 10µF, 25V
Taiyo Yuden TMK432BJ106KM
5V OUTPUTCOUT5, Output Capacitor2x 100µF, 6V, 35mΩ
SANYO 6TPE100MAZB
2x 100µF, 6V, 35mΩ
SANYO 6TPE100MAZB
L5/T5 Inductor/Transformer6.8µH, 6.4A, 18mΩ (max) 1:2
Sumida 4749-T132—
NH5 High-Side MOSFET
Fairchild Semiconductor
FDS6612A
International Rectifier
IRF7807V
Fairchild Semiconductor
FDS6612A
International Rectifier
IRF7807V
NL5 Low-Side MOSFET
Fairchild Semiconductor
FDS6670S
International Rectifier
IRF7807VD1
Fairchild Semiconductor
FDS6670S
International Rectifier
IRF7807VD1
3V OUTPUTCOUT3, Output Capacitor2x 150µF, 4V, 35mΩ
SANYO 4TPE150MAZB
2x 100µF, 6V, 35mΩ
SANYO 6TPE100MAZB
L3, Inductor5.7µH, 9A, 8.5mΩ
TDK RLF12560T-5R6N9R2
3.9µH, 6.5A, 15mΩ
Sumida CDRH124-3R9NC
NH3 High-Side MOSFET
Fairchild Semiconductor
FDS6612A
International Rectifier
IRF7807V
Fairchild Semiconductor
FDS6612A
International Rectifier
IRF7807V
NL3 Low-Side MOSFET
Fairchild Semiconductor
FDS6670S
International Rectifier
IRF7807VD1
Fairchild Semiconductor
FDS6670S
International Rectifier
IRF7807VD1
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook ComputersMAX8744
MAX8745
POWER GROUND
ANALOG GROUND
DH5
CLDO5
4.7μF
BST5
INPUT (VIN)
CSH5
CSL5
DL5
LX5
FB5
CIN
SEE TABLE 1 FOR COMPONENT SPECIFICATIONS.
ILIM
FSELREF
(300kHz)
POWER-GOOD
CREF
0.22μF
NL2
NH2
CBST2
0.1μF
DL2COUT2
PGOODA
NL1
NH1
CBST1
0.1μF
DL1COUT1
DH3
BST3
DL3
LX3
CSH3
CSL3
FB3
100kΩ
CONNECT
TO 5V OR 3.3V
5V PWM
OUTPUT
LDO5
3.3V PWM
OUTPUT
PGND
ONA
ON3
ON5
SHDN
OFFONSECONDARY
OUTPUTCAUX
4.7μF
PGOOD3
PGOOD54
GND8
5V LDO OUTPUT20
100kΩ R9
100kΩ
REF
CIN
OUTA
FBA
CLDOA
4.7μF
12V LDO
OUTPUT
110kΩ
10kΩ
DRVA2
SECONDARY
OUTPUT
5.62kΩ
3.92kΩ
0.22μF
10.5kΩ
4.02kΩ
0.22μF
R10
680Ω
1000pFC4
1000pF
SKIP
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook Computers
Detailed DescriptionThe MAX8744/MAX8745 standard application circuit
(Figure 1) generates the 5V/5A and 3.3V/5A typical of the
main supplies in a notebook computer. The input supply
range is 7V to 24V. See Table 1 for component selec-
tions, while Table 2 lists the component manufacturers.
The MAX8744/MAX8745 contain two interleaved, fixed-
frequency, step-down controllers designed for low-volt-
age power supplies. The optimal interleaved architecture
guarantees out-of-phase operation, reducing the input
capacitor ripple.One internal LDO generates the keep-
alive 5V power. The MAX8744/MAX8745 have an auxil-
iary LDO with an adjustable output for generating either
the 3.3V keep-alive supply or regulating the low-power
12V system supply.
Fixed 5V Linear Regulator (LDO5)An internal linear regulator produces a preset 5V low-
current output. LDO5 powers the gate drivers for the
external MOSFETs, and provides the bias supply
required for the SMPS analog controller, reference, and
logic blocks. LDO5 supplies at least 100mA for exter-
nal and internal loads, including the MOSFET gate
drive, which typically varies from 5mA to 50mA,
depending on the switching frequency and external
MOSFETs selected. Bypass LDO5 with a 4.7µF or
greater ceramic capacitor (1µF per 25mA of load) to
guarantee stability under the full-load conditions.
The MAX8744/MAX8745 switch-mode power supplies
(SMPS) require a 5V bias supply in addition to the high-
power input supply (battery or AC adapter). This 5V bias
supply is generated by the controller’s internal 5V linear
regulator (LDO5). This bootstrapped LDO allows the
controller to power up independently. The gate-driver
input supply is connected to the fixed 5V linear-regulator
output (LDO5). Therefore, the 5V LDO supply must pro-
vide LDO5 (PWM controller) and the gate-drive power,
so the maximum supply current required is:
IBIAS= ICC+ fSW(QG(LOW)+ QG(HIGH))
= 5mA to 50mA (typ)
where ICCis 0.7mA (typ), fSWis the switching frequency,
and QG(LOW)and QG(HIGH)are the MOSFET data
sheet’s total gate-charge specification limits at VGS= 5V.
SMPS to LDO Bootstrap SwitchoverWhen the 5V main output voltage is above the LDO5
bootstrap-switchover threshold and has completed
soft-start, an internal 1Ω(typ) p-channel MOSFET
shorts CSL5 to LDO5, while simultaneously shutting
down the LDO5 linear regulator. This bootstraps the
device, powering the internal circuitry and external
loads from the 5V SMPS output (CSL5), rather than
through the linear regulator from the battery. Boot-
strapping reduces power dissipation due to gate
charge and quiescent losses by providing power from
a 90%-efficient switch-mode source, rather than from a
much-less-efficient linear regulator. The current capa-
bility increases from 100mA to 200mA when the LDO5
output is switched over to CSL5. When ON5 is pulled
low, the controller immediately disables the bootstrap
switch and reenables the 5V LDO.
Reference (REF)The 2V reference is accurate to ±1% over temperature
and load, making REF useful as a precision system ref-
erence. Bypass REF to GND with a 0.1µF or greater
ceramic capacitor. The reference sources up to 50µA
and sinks 5µA to support external loads. If highly accu-
rate specifications are required for the main SMPS out-
put voltages, the reference should not be loaded.
Loading the reference reduces the LDO5, CSL5
(OUT5), CSL3 (OUT3), and OUTA output voltages
slightly because of the reference load-regulation error.
System Enable/Shutdown (SHDN)Drive SHDNbelow the precise SHDNinput falling-edge
trip level to place the MAX8744/MAX8745 in its low-
power shutdown state. The controller consumes only
8µA of quiescent current while in shutdown mode.
When shutdown mode activates, the reference turns off
after the controller completes the shutdown sequence
Table 2. Component Suppliers
SUPPLIERWEBSITEAVXwww.avx.com
Central Semiconductorwww.centralsemi.com
Fairchildwww.fairchildsemi.com
International Rectifierwww.irf.com
KEMETwww.kemet.com
NEC/Tokinwww.nec-tokin.com
Panasonicwww.panasonic.com/industrial
Philipswww.philips.com
Pulsewww.pulseeng.com
Renesaswww.renesas.com
SANYOwww.edc.sanyo.com
Sumidawww.sumida.com
Taiyo Yudenwww.t-yuden.com
TDKwww.component.tdk.com
TOKOwww.tokoam.com
Vishay (Dale, Siliconix)www.vishay.com
MAX8744/MAX8745
High-Efficiency, Quad-Output, Main Power-
Supply Controllers for Notebook ComputersREF
FB3
2.0V
REF
DH5
BST5
LX5
LDO5
DL5
PWM5
CONTROLLER
(FIGURE 3)
DH3
BST3
LX3
LDO5
DL3
PWM3
CONTROLLER
(FIGURE 3)
PGND
DECODE
(FIGURE 5)
ON3
FSEL
DECODE
(FIGURE 5)FB5
ON5
CSH5
CSL5
ILIM
CSH3
CSL3
PGOODA
POWER-GOOD AND FAULT
PROTECTION
(FIGURE 6)
INTERNAL
FAULT
FBA
OUTA
DRVA
ONA
SKIP
5V LINEAR
REGULATORLDO5
AUXILIARY
LINEAR REGULATOR
GND
LDO BYPASS
CIRCUITRY
OSC
SECONDARYFEEDBACK
SHDN
PGOOD3
PGOOD5
LDO5
MAX8744
MAX8745
Figure 2. Functional Diagram
