LTM4604资料

LTM4604Low Voltage, 4A DC/DC µModuleTM with TrackingFEATURES

Complete Standalone Power Supply■ Wide Input Voltage Range: 2.375V to 5.5V■ 4A DC, 5A Peak Output Current■ 0.8V to 5V Output■ Output Voltage Tracking■ ±2% Total DC Error■ UltraFastTM Transient Response■ Power Good Indicator■ Current Mode Control■ Current Foldback Protection, Parallel/Current Sharing■ Up to 95% Effi ciency■ Programmable Soft-Start■ Micropower Shutdown: IQ ≤ 7μA■ Overtemperature Protection■ Small and Very Low Profi le Package: 15mm × 9mm × 2.3mm LGA■DESCRIPTION

The LTM®4604 is a complete 4A switch mode DC/DC power supply. Included in the package are the switching control-ler, power FETs, inductor and all support components. Operating over an input voltage range of 2.375V to 5.5V, the LTM4604 supports an output voltage range of 0.8V to 5V, set by a single resistor. This high effi ciency design delivers up to 4A continuous current (5A peak). Only bulk output capacitors are needed to complete the design. The low profi le package (2.3mm) enables utilization of unused space on the bottom of PC boards for high density point of load regulation. High switching frequency and a current mode architecture enable a very fast transient response to line and load changes without sacrifi cing stability. The device supports output voltage tracking for supply rail sequencing.Fault protection features include foldback current protec-tion, thermal shutdown and a programmable soft-start function. The LTM4604 is offered in a space saving and thermally enhanced 15mm × 9mm × 2.3mm LGA package and is Pb free and RoHS compliant. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation.μModule and UltraFast are trademarks of Linear Technology Corporation.All other trademarks are the property of their respective owners.

APPLICATIONS

Telecom and Networking Equipment■ Servers■ Storage Cards■ ATCA Cards■ Industrial Equipment■TYPICAL APPLICATION

Effi ciency vs Output Current3.3V to 2.5V/4A μModule RegulatorVIN

3.3V10μF6.3VVINPGOODCOMPGNDVOUTFBVIN2.37kLTM4604RUN/SSTRACKVOUT2.5V4A22μF6.3V×24604 TA01a1009590EFFICIENCY (%)8580757065

VIN = 3.3VVOUT = 2.5V01

3

OUTPUT CURRENT (A)

24

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4604f1

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LTM4604ABSOLUTE MAXIMUM RATINGS

(Note 1)PIN CONFIGURATION

TOP VIEWTRACKA12345671011GNDVOUTLGA PACKAGE66-PIN (15mm ´ 9mm ´ 2.3mm)TJMAX = 125°C, θJA = 25°C/W, WEIGHT = 0.86gSWRUN/SSGNDBVINCOMPFBCDEPGOODFGVIN, PGOOD .................................................–0.3V to 6VCOMP, RUN/SS, FB, TRACK .........................–0.3V to VINSW, VOUT ........................................–0.3V to (VIN + 0.3V)Operating Temperature Range (Note 2) ...–40°C to 85°CJunction Temperature ...........................................125°CStorage Temperature Range ...................–55°C to 125°CORDER INFORMATION

LEAD FREE FINISHLTM4604EV#PBFLTM4604IV#PBFTRAYLTM4604EV#PBFLTM4604IV#PBFPART MARKING*LTM4604VLTM4604VPACKAGE DESCRIPTION15mm × 9mm × 2.3mm LGA15mm × 9mm × 2.3mm LGATEMPERATURE RANGE–40°C to 85°C–40°C to 85°CConsult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi ed by a label on the shipping container.Consult LTC Marketing for information on non-standard lead based fi nish parts.For more information on lead free part marking, go to: http://www.linear.com/leadfree/ This product is only offered in trays. For more information go to: http://linear.com/packaging/ELECTRICAL CHARACTERISTICS The ● denotes the specifi cations which apply over the full operating temperature range, otherwise specifi cations are at TA = 25°C. VIN = 5V unless otherwise noted. See Figure 15.PARAMETERCONDITIONSInput DC VoltageOutput Voltage, Total Variation CIN = 10μF × 1, COUT = 22μF ×3, RFB = 5.69k 0.5%with Line and Load VIN = 2.375V to 5.5V, IOUT = 0A to 4A, 0°C ≤ TA ≤ 85°C VIN = 2.375V to 5.5V, IOUT = 0A to 4AIOUT = 0AIOUT = 0A, CIN = 10μF, COUT = 22μF ×3, RUN/SS = 0.01μF, VOUT = 1.5V VIN = 3.3V VIN = 5VVIN = 3.3V, VOUT = 1.5V, No SwitchingVIN = 3.3V, VOUT = 1.5V, Switching ContinuousVIN = 5V, VOUT = 1.5V, No SwitchingVIN = 5V, VOUT = 1.5V, Switching ContinuousShutdown, RUN = 0, VIN = 5V●SYMBOLVIN(DC)VOUT(DC)MIN2.3751.4781.4701.75TYPMAX5.51.5221.5222.3UNITSVVVV●1.51.52Input Specifi cationsUndervoltage Lockout VIN(UVLO)ThresholdPeak Input Inrush Current at IINRUSH(VIN)Start-UpIQ(VIN NOLOAD)Input Supply Bias Current0.70.76028100357AAμAmAμAmAμA4604f2

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LTM4604ELECTRICAL CHARACTERISTICS The ● denotes the specifi cations which apply over the full operating temperature range, otherwise specifi cations are at TA = 25°C. VIN = 5V unless otherwise noted. See Figure 15.PARAMETERInput Supply CurrentCONDITIONSVIN = 2.5V, VOUT = 1.5V, IOUT = 4AVIN = 3.3V, VOUT = 1.5V, IOUT = 4AVIN = 5V, VOUT = 1.5V, IOUT = 4AVIN = 3.3V, VOUT = 1.5VMINSYMBOLIS(VIN)TYP2.92.21.45MAXUNITSAAAAOutput Specifi cationsIOUT(DC)Output Continuous Current Range (See Output Current Derating Curves for Different VIN, VOUT and TA)ΔVOUT(LINE)Line Regulation Accuracy VOUTΔVOUT(LOAD) VOUTVOUT(AC)fSΔVOUT(START)Output Ripple VoltageLoad Regulation Accuracy4VOUT = 1.5V, VIN from 2.375V to 5.5V, IOUT = 0AVOUT = 1.5V, 0A to 4A VIN = 3.3V VIN = 5VIOUT = 0A, COUT = 22μF/X5R/Ceramic ×3 VIN = 3.3V, VOUT = 1.5V VIN = 5V, VOUT = 1.5VIOUT = 4A, VIN = 5V, VOUT = 1.5VCOUT = 22μF ×3, VOUT = 1.5V, RUN/SS = 10nF, IOUT = 0A VIN = 3.3V VIN = 5VCOUT = 22μF ×3, VOUT = 1.5V, IOUT = 1A Resistive Load, TRACK = VIN and RUN/SS = Float VIN = 3.3V VIN = 5VLoad: 0% to 50% to 0% of Full Load, COUT = 22μF ×3 Ceramic VIN = 5V, VOUT = 1.5VLoad: 0% to 50% to 0% of Full Load VIN = 5V, VOUT = 1.5VCOUT = 22μF ×3 VIN = 3.3V, VOUT = 1.5V VIN = 5V, VOUT = 1.5VIOUT = 0A, VOUT = 1.5V, 0°C ≤ TA ≤ 85°CIOUT = 0A, VOUT = 1.5V●0.10.2%●●0.30.310121.250.60.6%%mVP-PmVP-PMHzOutput Ripple Voltage FrequencyTurn-On Overshoot2020mVmVtSTARTTurn-on Time1.51.0msmsΔVOUT(LS)tSETTLEIOUT(PK)Control SectionVFBIFBVRUNITRACKVTRACK(OFFSET)VTRACK(RANGE)RFBHIPGOODΔVPGOODRPGOODPeak Deviation for Dynamic Load StepSettling Time for Dynamic Load StepOutput Current Limit2510880.7920.7880.50.80.80.20.650.2304.990.8080.8120.8mVμsAAVVμAVμAmVVkΩVoltage at FB Pin●RUN Pin On/Off ThresholdTRACK Pin CurrentOffset VoltageTracking Input RangeResistor Between VOUT and FB PinsPGOOD RangePGOOD ResistanceTRACK = 0.4V04.9750.85.025Open-Drain Pull-Down±7.590150%ΩNote 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime.Note 2: The LTM4604E is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. The LTM4604I is guaranteed over the full –40°C to 85°C temperature range.4604f3

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LTM4604TYPICAL PERFORMANCE CHARACTERISTICS

Effi ciency vs Output CurrentVIN = 2.5V1009590EFFICIENCY (%)8580757065

VOUT = 1.8VVOUT = 1.5VVOUT = 1.2VVOUT = 0.8V0

1

3

OUTPUT CURRENT (A)

2

4

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Effi ciency vs Output CurrentVIN = 3.3V1009590EFFICIENCY (%)8580757065

VOUT = 2.5VVOUT = 1.8VVOUT = 1.5VVOUT = 1.2VVOUT = 0.8V0

1

3

OUTPUT CURRENT (A)

2

4

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Effi ciency vs Output CurrentVIN = 5V95908580757065

VOUT = 3.3VVOUT = 2.5VVOUT = 1.8VVOUT = 1.5VVOUT = 1.2VVOUT = 0.8V0

123OUTPUT CURRENT (A)

4

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Minimum Input Voltage at 4A Load3.53.02.5VOUT (V)2.01.51.00.50

VOUT = 3.3VVOUT = 2.5VVOUT = 1.8VVOUT = 1.5VVOUT = 1.2VVOUT = 0.8VEFFICIENCY (%)Load Transient ResponseLoad Transient ResponseILOAD2A/DIVVOUT20mV/DIV

ILOAD2A/DIVVOUT20mV/DIV

VIN = 5V20μs/DIVVOUT = 1.2V

COUT = 4 × 22μF, 6.3V CERAMICS

00.511.522.533.544.555.5

VIN (V)

4604 G04

4604 G05

VIN = 5V20μs/DIVVOUT = 1.5V

COUT = 4 × 22μF, 6.3V CERAMICS

4604 G06

Load Transient ResponseLoad Transient ResponseLoad Transient ResponseILOAD2A/DIVVOUT20mV/DIV

ILOAD2A/DIVILOAD2A/DIVVOUT20mV/DIV

VOUT20mV/DIV

20μs/DIVVIN = 5V

VOUT = 1.8V

COUT = 3 × 22μF, 6.3V CERAMICS

4604 G07

VIN = 5V20ms/DIVVOUT = 2.5V

COUT = 3 ´ 22mF, 6.3V CERAMICS

4604 G08

VIN = 5V20μs/DIVVOUT = 3.3V

COUT = 2 × 22μF, 6.3V CERAMICS

4604 G09

4604f4

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LTM4604TYPICAL PERFORMANCE CHARACTERISTICS

Start-UpStart-UpVOUT1V/DIVVOUT1V/DIV

IIN1A/DIV

IIN1A/DIV

VIN = 5V200μs/DIVVOUT = 2.5VCOUT = 4 × 22μFNO LOAD

(0.01μF SOFT-START CAPACITOR)

4604 G10

VIN = 5V200μs/DIVVOUT = 2.5VCOUT = 4 × 22μF4A LOAD

(0.01μF SOFT-START CAPACITOR)

4604 G11

VFB vs Temperature806804802VFB (mV)800798796794

VOUT (V)-50

-25

02550Temperature (C)

75

100

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Current Limit Foldback1.61.41.21.00.80.60.4

VOUT = 1.5VVIN = 5V0.2VIN = 3.3VVIN = 2.5V0

453

76

OUTPUT CURRENT (A)

8

4604 G12

Short-Circuit Protection1.5V Short, No LoadShort-Circuit Protection1.5V Short, 4A LoadVOUT0.5V/DIVVOUT0.5V/DIV

IIN4A/DIV

IIN1A/DIV

20μs/DIV

4604 G13

100μs/DIV

4604 G14

4604f5

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LTM4604PIN FUNCTIONS

VIN (B1, C1, C3-C7, D7, E6 and E7): Power Input Pins. Apply input voltage between these pins and GND pins. Recommend placing input decoupling capacitance directly between VIN pins and GND pins.VOUT (D8-D11, E8-E11, F6-F11, G6-G11): Power Output Pins. Apply output load between these pins and GND pins. Recommend placing output decoupling capacitance directly between these pins and GND pins. Review Table 4.GND (G3-G5, F3-F5, E4-E5, A1-A11, B6-B11, C8-C11): Power Ground Pins for Both Input and Output Returns.TRACK (E1): Output Voltage Tracking Pin. When the module is confi gured as a master output, then a soft-start capaci-tor is placed on the RUN/SS pin to ground to control the master ramp rate. Slave operation is performed by putting a resistor divider from the master output to ground, and connecting the center point of the divider to this pin on the slave regulator. If tracking is not desired, then connect the TRACK pin to VIN. Load current must be present for tracking. See Applications Information section. FB (G2): The Negative Input of the Error Amplifi er. Inter-nally, this pin is connected to VOUT with a 4.99k precision resistor. Different output voltages can be programmed with an additional resistor between FB and GND pins. Two power modules can current share when this pin is connected in parallel with the adjacent module’s FB pin. See Applications Information section.COMP (G1): Current Control Threshold and Error Amplifi er Compensation Point. The current comparator threshold increases with this control voltage. Two power modules can current share when this pin is connected in parallel with the adjacent module’s COMP pin.PGOOD (F1): Output Voltage Power Good Indicator. Open-drain logic output that is pulled to ground when the output voltage is not within ±7.5% of the regulation point.RUN/SS (D1): Run Control and Soft-Start Pin. A voltage above 0.8V will turn on the module, and below 0.5V will turn off the module. This pin has a 1M resistor to VIN and a 1000pF capacitor to GND. See Application Infomation section for soft-start information.SW (B3 and B4): Switching Node of the circuit is used for testing purposes. This can be connected to copper on the board to improve thermal performance. Make sure not to connect it to other output pins.PGOODFGCOMPSWRUN/SSGNDFBTOP VIEWTRACKA12345671011

GNDBVINCDEVOUT4604f6

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LTM4604BLOCK DIAGRAM

PGOODRSS1MCSS1000pFM1TRACKSUPPLY4.99k5.76kTRACKCOMPINTERNALCOMPCONTROL,DRIVEM2LC2470pFR14.99k0.5%10μF6.3VVOUT22μF6.3V×3GNDVOUT1.5V4A10μF6.3V×2VIN10μF6.3VVIN

2.375V TO 5.5VRUN/SSCSSEXT4604 BDFBRFB5.76kSWFigure 1. Simplifi ed LTM4604 Block DiagramDECOUPLING REQUIREMENTS TA = 25°C. Use Figure 1 Confi guration.SYMBOLCINCOUTPARAMETERExternal Input Capacitor Requirement (VIN = 2.375V to 5.5V, VOUT = 1.5V)External Output Capacitor Requirement (VIN = 2.375V to 5.5V, VOUT = 1.5V)CONDITIONSIOUT = 4AIOUT = 4AMIN1022100TYPMAXUNITSμFμF4604f7

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LTM4604OPERATION

Power Module DescriptionThe LTM4604 is a standalone non-isolated switch mode DC/DC power supply. It can deliver up to 4A of DC output current with few external input and output capacitors. This module provides a precise regulated output voltage programmable via one external resistor from 0.8V DC to 5.0V DC over a 2.375V to 5.5V input voltage. A typical application schematic is shown in Figure 15. The LTM4604 has an integrated constant frequency cur-rent mode regulator with built-in power MOSFETs with fast switching speed. The typical switching frequency is 1.25MHz. With current mode control and internal feedback loop compensation, the LTM4604 module has suffi cient stability margins and good transient performance under a wide range of operating conditions and with a wide range of output capacitors, even all ceramic output capacitors. Current mode control provides cycle-by-cycle fast current limit. In addition, foldback current limiting is provided in an overcurrent condition while VOUT drops. Internal overvoltage and undervoltage comparators pull the open-drain PGOOD output low if the output feedback voltage exits a ±7.5% window around the regulation point. Furthermore, in an overvoltage condition, internal top FET M1 is turned off and bottom FET M2 is turned on and held on until the overvoltage condition clears. Pulling the RUN pin below 0.5V forces the controller into its shutdown state, turning off both M1 and M2. At low load current, the module works in continuous current mode by default to achieve minimum output voltage ripple. The TRACK pin is used for power supply tracking. See the Applications Information section.The LTM4604 is internally compensated to be stable over a wide operating range. Table 4 provides a guideline for input and output capacitance for several operating condi-tions. An excel loop analysis tool is provided for transient and stability analysis.The FB pin is used to program the output voltage with a single resistor connected to ground.4604f8

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LTM4604APPLICATIONS INFORMATION

A typical LTM4604 application circuit is shown in Figure 15. External component selection is primarily determined by the maximum load current and output voltage. Refer to Table 4 for specifi c external capacitor requirements for a particular application.VIN to VOUT Step-Down RatiosThere are restrictions in the maximum VIN and VOUT step-down ratio that can be achieved for a given input voltage. The LTM4604 is 100% duty cycle, but the VIN to VOUT minimum dropout is a function of the load current. A typi-cal 0.5V minimum is suffi cient (see Typical Performance Characteristics).Output Voltage Programming The PWM controller has an internal 0.8V reference voltage. As shown in the Block Diagram, a 4.99k, 0.5% internal feedback resistor connects the VOUT and FB pins together. The output voltage will default to 0.8V with no feedback resistor. Adding a resistor RFB from the FB pin to GND programs the output voltage:VOUT=0.8V•

4.99k+RFBRFB

1.2V10k1.5V5.76k1.8V4.02k2.5V2.37k3.3V1.62kWithout considering the inductor current ripple, the RMS current of the input capacitor can be estimated as:ICIN(RMS)=

IOUT(MAX)η%

•D•(1–D) In the above equation, η% is the estimated effi ciency of the power module. The bulk capacitor can be a switcher-rated electrolytic aluminum capacitor, OS-CON capacitor for bulk input capacitance due to high inductance traces or leads. If a low inductance plane is used to power the device, then no input capacitance is required. The two internal 10μF ceramics are typically rated for 2A to 3A of RMS ripple current. The worst-case ripple current for the 4A maximum current is 2A or less.Output CapacitorsThe LTM4604 is designed for low output voltage ripple. The bulk output capacitors defi ned as COUT are chosen with low enough effective series resistance (ESR) to meet the output voltage ripple and transient requirements. COUT can be a low ESR tantalum capacitor, a low ESR polymer capacitor or an X5R/X7R ceramic capacitor. The typical output capacitance range is 22μF to 100μF. Additional output fi ltering may be required by the system designer if further reduction of output ripple or dynamic transient spike is required. Table 4 shows a matrix of different output voltages and output capacitors to minimize the voltage droop and overshoot during a 2A/μs transient. The table optimizes the total equivalent ESR and total bulk capacitance to maximize transient performance. The Linear Technology μModule Power Design Tool can be for further optimization.Fault Conditions: Current Limit and Overcurrent FoldbackThe LTM4604 has current mode control, which inher-ently limits the cycle-by-cycle inductor current not only in steady-state operation, but also in transient. To further limit current in the event of an overload condi-tion, the LTM4604 provides foldback current limiting as the output voltage falls. The LTM4604 device has over-temperature shutdown protection that inhibits switching operation around 150°C.4604f Table 1. FB Resistor vs Output VoltageVOUTRFB0.8VOpenInput CapacitorsThe LTM4604 module should be connected to a low ac-impedance DC source. Two 10μF ceramic capacitors are included inside the module. Additional input capacitors are only needed if a large load step is required up to a full 4A level. An input 47μF bulk capacitor is only needed if the input source impedance is compromised by long inductive leads or traces. For a buck converter, the switching duty cycle can be estimated as:D= VOUTVIN

9

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LTM4604APPLICATIONS INFORMATION

Run Enable and Soft-StartThe RUN/SS pin provides dual functions of enable and soft-start control. The RUN/SS pin is used to control turn on of the LTM4604. While this pin is below 0.5V, the LTM4604 will be in a 7μA low quiescent current state. A 0.8V threshold will enable the LTM4604. This pin can be used to sequence LTM4604 devices. The soft-start control is provided by a 1M pull-up resistor (RSS) and a 1000pF capacitor (CSS) as drawn in the Block Diagram. An external capacitor can be applied to the RUN/SS pin to increase the soft-start time. A typical value is 0.01μF. The approximate equation for soft-start is:tSOFTSTART ⎛VIN⎞=ln⎜•RSS(CSS+CSSEXT)⎝VIN–1.8V⎟⎠

CIN110μF6.3VX5R OR X7RVINPGOODCOMPGNDVOUTFBRAMPCONTROLOR VINRFB31.62kCOUT122μF6.3V ×3X5R ORX7RLTM4604RUN/SSTRACKCSSEXTVMASTER3.3V4A

VIN5VVIN5VCIN210μF6.3VX5R OR X7RVINPGOODCOMPGNDVOUTFBRFB25.76kRFB5.76kCOUT222μF6.3V ×3X5R ORX7RLTM4604RUN/SSTRACKVSLAVE1.5V4A

where RSS and CSS are shown in the Block Diagram of Figure 1, 1.8V is the soft-start upper range, and CSSEXT is the additional capacitance for further soft-start contol. The soft-start function can also be used to control the output ramp-up time, so that another regulator can be easily tracked. An independent ramp control signal can be applied to the master ramp, otherwise, connect the TRACK pin to VIN to disable tracking.Output Voltage Tracking Output voltage tracking can be programmed externally using the TRACK pin. The output can be tracked up and down with another regulator. The master regulator’s output is divided down with an external resistor divider that is the same as the slave regulator’s feedback divider to implement coincident tracking. The LTM4604 uses a very accurate 4.99k resistor for the top feedback resistor. Figure 2 shows an example of coincident tracking.VTRACK=

RFB2•V

4.99k+RFB2MASTER

RFB14.99k4604 F02Figure 2MASTER OUTPUT

OUTPUT VOLTAGE (V)SLAVE OUTPUT

TIME

4604 F03

VTRACK is the track ramp applied to the slave’s TRACK pin. VTRACK applies the track reference for the slave output up to the point of the programmed value at which VTRACK proceeds beyond the 0.8V reference value. The VTRACK pin must go beyond 0.8V to ensure the slave output has reached its fi nal value. Load current must be present for proper tracking.Figure 34604f10

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LTM4604APPLICATIONS INFORMATION

Ratio metric modes of tracking can be achieved by selecting different resistor values to change the output tracking ratio. The master output must be greater than the slave output for the tracking to work. Linear Technology Tracker Cad26 can be used to implement different tracking scenarios. The Master and Slave data inputs can be used to implement the correct resistor values for coincident or ratio tracking. The master and slave regulators require load current for tracking down. Power GoodThe PGOOD pin is an open-drain pin that can be used to monitor valid output voltage regulation. This pin monitors a ±7.5% window around the regulation point.COMP PinThe pin is the external compensation pin. The module has already been internally compensated for all output voltages. Table 4 is provided for most application require-ments. A spice model will be provided for other control loop optimizations.Parallel OperationThe LTM4604 device is an inherently current mode con-trolled device. Parallel modules will have very good current sharing. This will balance the thermals on the design. Figure 16 shows a schematic of the parallel design. The voltage feedback changes with the variable N as more modules are paralleled. The equation: VOUT

4.99k

+RFBN=0.8V•

RFB

N is the number of paralleled modules.Thermal Considerations and Output Current DeratingThe power loss curves in Figures 4 and 5 can be used in coordination with the load derating curves in Figures 6 through 13 for calculating an approximate θJA for the module with and without heat sinking methods with vari-ous airfl ow conditions. Thermal models are derived from several temperature measurements at the bench, and are correlated with thermal analysis software. Tables 2 and 3 provide a summary of the equivalent θJA for the noted conditions. These equivalent θJA parameters are correlated to the measured values and improve with air fl ow. The maximum junction temperature is monitored while the derating curves are derived. 2.01.81.61.4WATTS1.21.00.80.6

5V TO 2.5VPOWER LOSS3.3V TO 2.5VPOWER LOSS0

1

23LOAD CURRENT (A)

4

5

4604 F05

2.01.81.61.4WATTS1.21.00.80.60.40.200

1

5V TO 1.2VPOWER LOSS3.3V TO 1.2VPOWER LOSS32

LOAD CURRENT (A)

4

5

4604 F04

0.40.20

Figure 4. 1.2V Power LossFigure 5. 2.5V Power Loss4604f11

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LTM4604APPLICATIONS INFORMATION

4.03.5LOAD CURRENT (A)LOAD CURRENT (A)0LFM200LFM400LFM70

75

80859095100105110115AMBIENT TEMPERATURE (°C)

4606 F06

4.03.53.02.52.01.51.00.5070

750LFM200LFM400LFM80859095100105110115AMBIENT TEMPERATURE (°C)

4606 F07

3.02.52.01.51.00.50

Figure 6. 5VIN to 1.2VOUT No Heat Sink4.03.5LOAD CURRENT (A)LOAD CURRENT (A)0LFM200LFM400LFM70

75

80859095100105110115AMBIENT TEMPERATURE (°C)

4606 F08

Figure 7. 5VIN to 1.2VOUT with Heat Sink4.03.53.02.52.01.51.00.5070

750LFM200LFM400LFM80859095100105110115AMBIENT TEMPERATURE (°C)

4606 F09

3.02.52.01.51.00.50

Figure 8. 3.3VIN to 1.2VOUT No Heat Sink4.03.5LOAD CURRENT (A)3.02.52.01.51.00.5070

750LFM200LFM400LFM80859095100105110AMBIENT TEMPERATURE (°C)

4606 F10

Figure 9. 3.3VIN to 1.2VOUT with Heat Sink4.03.5LOAD CURRENT (A)3.02.52.01.51.00.5070

750LFM200LFM400LFM80859095100105110115AMBIENT TEMPERATURE (°C)

4606 F11

Figure 10. 5VIN to 2.5VOUT No Heat SinkFigure 11. 5VIN to 2.5VOUT with Heat Sink4604f12

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LTM4604APPLICATIONS INFORMATION

4.03.5LOAD CURRENT (A)LOAD CURRENT (A)0LFM200LFM400LFM70

75

80859095100105110115AMBIENT TEMPERATURE (°C)

4606 F12

4.03.53.02.52.01.51.00.5070

750LFM200LFM400LFM80859095100105110115AMBIENT TEMPERATURE (°C)

4606 F13

3.02.52.01.51.00.50

Figure 12. 3.3VIN to 2.5VOUT No Heat SinkFigure 13. 3.3VIN to 2.5VOUT with Heat Sink4604f13

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LTM4604APPLICATIONS INFORMATION

Table 2. 1.2V OutputDERATING CURVEFigures 6, 8Figures 6, 8Figures 6, 8 Figures 7, 9 Figures 7, 9Figures 7, 9VIN (V)3.3, 53.3, 53.3, 53.3, 53.3, 53.3, 5POWER LOSS CURVEFigure 4Figure 4 Figure 4Figure 4Figure 4 Figure 4AIR FLOW (LFM)02004000200400HEAT SINKNoneNoneNoneBGA Heat SinkBGA Heat SinkBGA Heat SinkθJA (°C/W)2522.521212018Table 3. 2.5V OutputDERATING CURVEFigures 10, 12Figures 10, 12 Figures 10, 12 Figures 11, 13Figures 11, 13Figures 11, 13VIN (V)3.3, 53.3, 53.3, 53.3, 53.3, 53.3, 5POWER LOSS CURVEFigure 5Figure 5Figure 5Figure 5Figure 5Figure 5AIR FLOW (LFM)02004000200400HEAT SINKNoneNoneNoneBGA Heat SinkBGA Heat SinkBGA Heat SinkθJA (°C/W)252121211816Table 4. Output Voltage Response Versus Component Matrix (Refer to Figure 17), 0A to 2A Load Step Typical Measured ValuesCINVOUT (V)(CERAMIC)1.21.21.21.51.51.51.81.81.82.52.52.53.33.33.310μF10μF10μF10μF10μF10μF10μF10μF10μF10μF10μF10μF10μF10μF10μFCIN (Bulk)56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF Aluminum56μF AluminumCOUT(CERAMIC)100μF 6.3V22μF ×422μF ×4100μF 6.3V22μF ×422μF ×4100μF 6.3V22μF ×322μF ×3100μF 6.3V22μF ×322μF ×3100μF 6.3V22μF ×322μF ×3CCOMPNoneNoneNoneNoneNoneNoneNoneNoneNoneNoneNoneNoneNoneNoneNoneVIN (V)2.53.352.53.352.53.352.53.352.53.35DROOP(mV)212324192121253030222525222525PEAK-TO-PEAK(mV)4345414343506060455555505656RECOVERYLOAD STEP (μs)(A/μs)101010101010101010121212151515222222222222222RFB(kΩ)1010105.765.765.7.024.024.022.372.372.371.621.621.624604f14

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LTM4604APPLICATIONS INFORMATION

Safety ConsiderationsThe LTM4604 modules do not provide isolation from VIN to VOUT. There is no internal fuse. If required, a slow blow fuse with a rating twice the maximum input current needs to be provided to protect each unit from catastrophic failure. Layout Checklist/ExampleThe high integration of LTM4604 makes the PCB board layout very simple and easy. However, to optimize its electri-cal and thermal performance, some layout considerations are still necessary. • Use large PCB copper areas for high current path, including VIN, GND and VOUT. It helps to minimize the PCB conduction loss and thermal stress. • Place high frequency ceramic input and output capacitors next to the VIN, GND and VOUT pins to minimize high frequency noise. • Place a dedicated power ground layer underneath the unit. • To minimize the via conduction loss and reduce module thermal stress, use multiple vias for interconnection between top layer and other power layers. VIN• Do not put vias directly on the pads unless they are capped.• SW pads can be soldered to board to improve thermal performance.Figure14 gives a good example of the recommended layout.GNDVOUTCOUTCOUTCOUT••••••••CIN•••••••••••••••••••••••••••••••••••••••••••••SW••••••••••••GND••4604 F14Figure 14. Recommended PCB LayoutVIN

2.375V TO 5.5VCIN10μF6.3VX5R OR X7ROPEN-DRAINPULL UPVINPGOODCOMPCSSEXT0.01μFGNDVOUTFBRFB5.69k0.5%LTM4604RUN/SSTRACKVOUT1.5V4A

COUT22μF ×36.3VX5R OR X7RREFER TOTABLE 44604 F15Figure 15. Typical 2.375V to 5.5V Input, 1.5V at 4A Design4604f15

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LTM4604TYPICAL APPLICATIONS

VIN

2.375V TO 5VCIN110μF6.3VX5R OR X7ROPEN-DRAIN PULL UPVINPGOODCOMPCSSEXT0.01μFGNDVOUTFBRFB2.87kCOUT122μF ×36.3VX5R OR X7RREFER TOTABLE 4VOUT1.5V8ACIN210μF6.3VX5R OR X7RVINPGOODCOMPGND4604 F16VOUT = 0.8V × ((4.99k/N) + RFB)/RFBWHERE N IS THE NUMBER OF PARALLEL DEVICESLTM4604RUN/SSTRACKVOUTFBCOUT222μF ×36.3VX5R OR X7RREFER TOTABLE 4LTM4604RUN/SSTRACKFigure 16. Two LTM4604s in Parallel, 1.5V at 8A Design4604f16

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LTM4604TYPICAL APPLICATIONS

VIN3.3V TO 5VCIN10μF6.3VX5R OR X7R50kOPEN-DRAIN

PULL UP

VINPGOODCOMPCSSEXT0.01μFGNDVOUTFBRFB2.37kLTM4604RUN/SSTRACKVOUT2.5V4A

COUT22μF ×36.3VX5R OR X7RREFER TOTABLE 44604 F17Figure 17. 3.3V to 5V Input, 2.5V at 4A Design4604f17

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4aaa Zbbb ZPAD “A1”CORNERZ6.3505.0803.8102.5401.2700.44450.0000.44451.2702.5403.8105.0806.35018

LGA Package66-Lead (15mm × 9mm × 2.32mm)(Reference LTC DWG # 05-08-1807 Rev A)XY15.00BSC2.19 – 2.4512.70BSC0.8 – 0.914GF0.8 – 0.914EDCBAPADSSEE NOTES111098765PACKAGE BOTTOM VIEW4321PAD 1PACKAGE DESCRIPTION

9.00BSC1.90 – 2.100.29 – 0.35MOLDCAPSUBSTRATE7.620BSCDETAIL A1.27BSCPACKAGE TOP VIEWDETAIL APACKAGE SIDE VIEW3NOTES:1. DIMENSIONING AND TOLERANCING PER ASME Y14.5M-19942. ALL DIMENSIONS ARE IN MILLIMETERS3 LAND DESIGNATION PER JESD MO-2224DETAILS OF PAD #1 IDENTIFIER ARE OPTIONAL,BUT MUST BE LOCATED WITHIN THE ZONE INDICATED.THE PAD #1 IDENTIFIER MAY BE EITHER A MOLD OR A MARKED FEATURE3.8102.5401.2705. PRIMARY DATUM -Z- IS SEATING PLANE6. THE TOTAL NUMBER OF PADS: 66SYMBOLTOLERANCE0.15aaa0.10bbbCOMPONENTPIN “A1”TRAY PIN 1BEVELLTMXXXXXXmModule0.44450.0000.44451.2702.5403.810PACKAGE IN TRAY LOADING ORIENTATIONLGA 66 0607 REV ASUGGESTED PCB LAYOUTTOP VIEW4604f元器件交易网www.cecb2b.com

LTM4604PACKAGE DESCRIPTION

Pin Assignment Table(Arranged by Pin Number)PIN NAMEA1 GNDA2 GNDA3 GNDA4 GNDA5 GNDA6 GNDA7 GNDA8 GNDA9 GNDA10 GNDA11 GNDPIN NAMEB1 VINB2 –B3 SWB4 SWB5 –B6 GNDB7 GNDB8 GNDB9 GNDB10 GNDB11 GNDPIN NAMEC1 VINC2 –C3 VINC4 VINC5 VINC6 VINC7 VINC8 GNDC9 GNDC10 GNDC11 GNDPIN NAMED1 RUN/SSD2 –D3 –D4 –D5 –D6 –D7 VIND8 VOUTD9 VOUTD10 VOUTD11 VOUTPIN NAMEE1 TRACKE2 –E3 –E4 GNDE5 GNDE6 VINE7 VINE8 VOUTE9 VOUTE10 VOUTE11 VOUTPIN NAMEF2 –F3 GNDF4 GNDF5 GNDF6 VOUTF7 VOUTF8 VOUTF9 VOUTF10 VOUTF11 VOUTPIN NAMEG2 FBG3 GNDG4 GNDG5 GNDG6 VOUTG7 VOUTG8 VOUTG9 VOUTG10 VOUTG11 VOUTF1 PGOODG1 COMP4604fInformation furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.19

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LTM4604RELATED PARTS

PART NUMBERLTC2900LTC2923LTM4600LTM4601LTM4602LTM4603LTM4608DESCRIPTIONQuad Supply Monitor with Adjustable Reset TimerPower Supply Tracking Controller10A DC/DC μModule12A DC/DC μModule with PLL, Output Tracking/ Margining and Remote Sensing6A DC/DC μModule6A DC/DC μModule with PLL and Output Tracking/Margining and Remote Sensing8A Low Voltage μModuleCOMMENTSMonitors Four Supplies; Adjustable Reset TimerTracks Both Up and Down; Power Supply SequencingBasic 10A DC/DC μModuleSynchronizable, PolyPhase Operation, LTM4601-1 Version has no Remote SensingPin Compatible with the LTM4600Synchronizable, PolyPhase Operation, LTM4603-1 Version has no Remote Sensing, Pin Compatible with the LTM46012.375V ≤ VIN ≤ 5V, Parallel for Higher Output Current, 9mm × 15mm × 2.8mm4604f20

Linear Technology CorporationLT 0807 • PRINTED IN USA

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