比重的英文译语怎么说-阿基米德定律
2023鹊桥仙古诗 年4月5日发(作者：俄罗斯音乐学院)
PROGRAMMABLESYNCHRONOUSDC/DC
CONVERTER,DUALLOWDROPOUT
REGULATORCONTROLLER
1999SEMTECHCORP.
PRELIMINARY-December2,1999
652MITCHELLROADNEWBURYPARKCA91320
SC1186
1
DESCRIPTION
TheSC1186combinesasynchronousvoltagemode
controllerwithtwolow-dropoutlinearregulators
providingmostofthecircuitrynecessaryto
implementthreeDC/DCconvertersforpowering
advancedmicroprocessorssuchasPentiumII&III.
TheSC1186switchingsectionfeaturesanintegrated
5bitD/Aconverter,latcheddriveoutputfor
enhancednoiseimmunity,pulsebypulsecurrent
1186
switchingsectionoperatesatafixedfrequencyof
140kHz,providinganoptimumcompromisebetween
size,efficiencyandcostintheintendedapplication
egratedD/Aconverterprovides
programmabilityofoutputvoltagefrom2.0Vto3.5V
in100mVincrementsand1.30Vto2.05Vin50mV
incrementswithnoexternalcomponents.
TheSC1186linearsectionsarelowdropoutregula-
torswithshortcircuitprotection,supplying1.5Vfor
GTLbusand2.5Vfornon-GTLI/erence
voltageismadeavailableforexternallinear
regulators.
PentiumisaregisteredtrademarkofIntelCorporation
TEL:805-498-2111FAX:805-498-3804WEB:
BLOCKDIAGRAM
R
S
Q
+
-
70mV
+
-
+
-
2.5VFET
CONTROLLER
1.5VFET
CONTROLLER
1.265V
REF
ERROR
AMP
D/A
SHOOT-THRU
CONTROL
VCCCS-
BSTH
DH
PGNDH
ENCS+
BSTL
DL
PGNDL
VOSENSE
LDOEN
LDOS2
VID3
LDOS1
VID2
VID1
VID0
AGND
REF
GATE2
GATE1
LDOVREF
VID4
CURRENT
LIMIT
LEVELSHIFTAND
HIGHSIDEDRIVE
SYNCHRONOUS
MOSFETDRIVE
OSCILLATOR
PINCONFIGURATION
AGND
GATE1
LDOS1
LDOS2
VCC
REF
LDOEN
CS-
CS+
PGNDH
DH
PGNDL
1
2
3
LDOV
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
VOSENSE
EN
BSTH
BSTL
DL
VID0
VID1
VID2
VID3
VID4
GATE2
TopView
(24PinSOIC)
FEATURES
•Synchronousdesign,enablesnoheatsinksolution
•95%efficiency(switchingsection)
•5bitDACforoutputprogrammability
•DesignedforIntelPentiumll&IIIrequirements
•1.5V,2.5Vshortcircuitprotectedlinearcontrollers
•1.265V1.5%Referenceavailable
APPLICATIONS
•Pentiumll&IIImicroprocessorsupplies
•Flexiblemotherboards
•1.3Vto3.5Vmicroprocessorsupplies
•Programmabletriplepowersupplies
ORDERINGINFORMATION
PartNumber(1)Package
Linear
Voltage
Temp.
Range(T
J
)
SC1186CSWSO-241.5V/2.5V0to125C
Note:
(1)Addsuffix‘TR’fortapeandreel.
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1999SEMTECHCORP.
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652MITCHELLROADNEWBURYPARKCA91320
SC1186
2
ParameterSymbolMaximumUnits
VCCtoGNDV
IN
-0.3to+7V
PGNDtoGND1V
BSTtoGND-0.3to+15V
OperatingTemperatureRangeT
A
0to+70C
JunctionTemperatureRangeT
J
0to+125C
StorageTemperatureRangeT
STG
-65to+150C
LeadTemperature(Soldering)10secondsT
L
300C
ThermalImpedanceJunctiontoAmbient
JA
80C/W
ThermalImpedanceJunctiontoCase
JC
25C/W
ABSOLUTEMAXIMUMRATINGS
ELECTRICALCHARACTERISTICS
Unlessspecified:V
CC
=4.75Vto5.25V;GND=P
GND
=0V;V
OSENSE
=V
O
;0mV<(CS+-CS-)<60mV;LDOV=11.4Vto12.6V;T
A
=0to70C
PARAMETERCONDITIONSMINTYPMAXUNITS
SwitchingSection
OutputVoltageI
O
=2AinApplicationCircuitSeeOutputVoltageTable
SupplyVoltageVCC4.57V
SupplyCurrentVCC=5.0V815mA
LoadRegulationI
O
=0.8Ato15A1%
LineRegulation0.15%
CurrentLimitVoltage607085mV
OscillatorFrequency120140160kHz
OscillatorMaxDutyCycle9095%
PeakDHSink/SourceCurrentBSTH-DH=4.5V,DH-PGNDH=3.3V
DH-PGNDH=1.5V
1
100
A
mA
PeakDLSink/SourceCurrentBSTL-DL=4.5V,DL-PGNDL=3.3V
DL-PGNDL=1.5V
1
100
A
mA
Gain(A
OL
)VOSENSEtoV
O
35dB
VIDSourceCurrent
VIDx
≤
2.4V
110A
VIDLeakageVIDx=5V10A
PowerGoodThresholdVoltage88112%
DeadTime40100ns
LinearSections
QuiescentCurrentLDOV=12V5mA
OutputVoltageLDO12.4932.5252.556V
OutputVoltageLDO21.4961.5151.534V
ReferenceVoltage
Iref
≤
100A
1.2461.2651.284V
Gain(A
OL
)LDOS(1,2)toGATE(1,2)90dB
LoadRegulationI
O
=0to8A0.3%
LineRegulation0.3%
OutputImpedanceV
GATE
=6.5V11.5
k
Ω
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652MITCHELLROADNEWBURYPARKCA91320
SC1186
3
AGND
GATE1
LDOS1
LDOS2
VCC
REF
LDOEN
CS-
CS+
PGNDH
DH
PGNDL
1
2
3
LDOV
4
5
6
7
8
9
10
11
12
24
23
22
21
20
19
18
17
16
15
14
13
VOSENSE
EN
BSTH
BSTL
DL
VID0
VID1
VID2
VID3
VID4
GATE2
TopView
(24PinSOIC)
Note:
(1)Alllogiclevelinputsandoutputsareopen
collectorTTLcompatible.
PINDESCRIPTION
PinPinNamePinFunction
1AGNDSmallSignalAnalogandDigitalGround
2GATE1GateDriveOutputLDO1
3LDOS1SenseInputforLDO1
4LDOS2SenseInputforLDO2
5VCCInputVoltage
6REFBufferedReferenceVoltageoutput
7LDOENLDOSupplyMonitor.
8CS-CurrentSenseInput(negative)
9CS+CurrentSenseInput(positive)
10PGNDHPowerGroundforHighSideSwitch
11DHHighSideDriverOutput
12PGNDLPowerGroundforLowSideSwitch
13DLLowSideDriverOutput
14BSTLSupplyforLowSideDriver
15BSTHSupplyforHighSideDriver
16EN(1)Logiclowshutsdowntheconverter;
Highoropenfornormaloperation.
17VOSENSETopendofinternalfeedbackchain
18
VID4(1)ProgrammingInput(MSB)
19
VID3(1)ProgrammingInput
20
VID2(1)ProgrammingInput
21
VID1(1)ProgrammingInput
22
VID0(1)ProgrammingInput(LSB)
23LDOV+12VforLDOsection
24GATE2GateDriveOutputLDO2
ELECTRICALCHARACTERISTICS(Cont.)
Unlessspecified:V
CC
=4.75Vto5.25V;GND=P
GND
=0V;V
OSENSE
=V
O
;0mV<(CS+-CS-)<60mV;LDOV=11.4Vto12.6V;T
A
=0to70C
PARAMETERCONDITIONSMINTYPMAXUNITS
LDOVUndervoltageLockout6.58.010V
LDOENThreshold1.31.9V
LDOENSinkCurrentLDOEN=3.3V
LDOEN=0V
0.01
-200
1.0
-300
A
A
OvercurrentTripVoltage%ofVosetpoint204060%
Power-upOutputShortCircuitImmunity1560ms
OutputShortCircuitGlitchImmunity0.546ms
GatePulldownImpedanceGATE(1,2)-AGND;VCC=BST=0V80300750
k
Ω
VOSENSEImpedance10
k
Ω
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PROGRAMMABLESYNCHRONOUSDC/DC
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REGULATORCONTROLLER
1999SEMTECHCORP.
PRELIMINARY-December2,1999
652MITCHELLROADNEWBURYPARKCA91320
SC1186
4
OUTPUTVOLTAGE
Unlessspecified:4.75V
O
;0mV<(CS+-CS-)<60mV;
=0C
j
<85C
Standard
PARAMETERVID
43210
MINTYPMAXUNITS
OutputVoltage011111.2771.3001.323V
011101.3261.3501.374
011011.3751.4001.425
011001.4241.4501.476
010111.4781.5001.523
010101.5271.5501.573
010011.5761.6001.624
010001.6251.6501.675
001111.6751.7001.726
001101.7241.7501.776
001011.7821.8001.818
001001.8321.8501.869
000111.8811.9001.919
000101.9311.9501.970
000011.9802.0002.020
000002.0302.0502.071
111111.9702.0002.030
111102.0692.1002.132
111012.1672.2002.233
111002.2662.3002.335
110112.3642.4002.436
110102.4632.5002.538
110012.5612.6002.639
110002.6602.7002.741
101112.7582.8002.842
101102.8422.9002.958
101012.9403.0003.060
101003.0383.1003.162
100113.1363.2003.264
100103.2343.3003.366
100013.3323.4003.468
100003.4303.5003.570
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PRELIMINARY-December2,1999
652MITCHELLROADNEWBURYPARKCA91320
SC1186
5
V
C
C
_
C
O
R
E
2.
5
V
1.
5
V
G
N
D
VI
D
0
VI
D
1
VI
D
2
VI
D
3
VI
D
4
1
2
V
5
V
E
N
R
E
F
3.
3
V
C
1
0.
1
u
F
L
1
4
u
H
R
4
5
m
O
h
m
C
1
8
0.
1
u
F
+
C
1
4
1
5
0
0
u
F
+
C
1
5
1
5
0
0
u
F
+
C
1
6
1
5
0
0
u
F
+
C
1
7
1
5
0
0
u
F
+
C
3
1
5
0
0
u
F
+
C
2
1
5
0
0
u
F
R
1
1
0
C
1
3
0.
1
u
F
Q
2
I
R
L
3
4
0
2
5
Q
1
I
R
L
3
4
0
2
5
C
5
0.
1
u
F
Q
3
I
R
L
M
L
2
8
0
3
+
C
1
1
3
3
0
u
F
R
5
2.
3
2
k
U
1
S
C
1
1
8
6
C
S
W
A
G
N
D
1
V
C
C
5
R
E
F
6
L
D
O
E
N
7挽起的近义词
C
S-
8
C
S
+
9
P
G
N
D
H
1
0
D
H
1
1
B
S
T
H
1
5
E
N
1
6
V
O
S
E
N
S
E
1
7
VI
D
4
1
8
VI
D
3
1
9
VI
D
2
2
0
VI
D
1
2
1
VI
D
0
2
2
D
L
1
3
P
G
N
D
L
1
2
B
S
T
L
1
4
G
A
T
E
2
2
4
G
A
T
E
1
2
L
D
O
V
2
3
L
D
O
S
1
3
L
D
O
S
2
4
Q
4
I
R
F
Z
1
4
S
+
C
9
1
0
0
0
u
F
R
6
1.
0
0
k
C
2
1
+
3
3
0
u
F
APPLICATIONCIRCUIT
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SC1186
6
MA向来枉费推移力此日中流自在行 TERIALSLIST
ncePart/DescriptionVendorNotes
4C1,C5,C13,C180.1FCeramicVarious
6C2,C3,C14-C171500F/
1C91000F
2C11,C21330F/6.3VVarious
1L14H8Turns16AWGonMICROMETALST50-52Dcore
2Q1,Q2SeenotesSeenotesFETselectionrequirestrade-offbetweenefficiencyand
temaximumR
DS(ON)
=22m
Ω
forQ1,Q2
1Q3IRLML2803IR
.25
Ω
30VSOT23(orequivalent)
1Q4IRFZ14SIROrequivalent
1R4
5m
Ω
IRCOAR-1Series
1R5
2.32k
Ω
,1%,1/8W
Various
1R6
1k
Ω
,1%,1/8W
Various
1R1
10
Ω
,5%,1/8W
Various
1U1SC1186CSWSEMTECH
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SC1186
7
TypicalRipple,Vo=2.0V,Io=10A
TransientResponseVo=2.4V,Io=300mAto15A
76%
80%
84%
88%
92%
96%
0.02.04.06.08.010.012.014.016.0
Io(Amps)
Ef
f
i
ci
e
n
c
y
(
%)
Vo=2.8V
Vo=2.0V
Vo=2.5V
TypicalEfficiency(Switchingsection)
2.5VLinearShortcircuitoutputresponse
OutputVoltage
OutputCurrent
5A/div
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SC1186
8
LAYOUTGUIDELINES
Carefulattentiontolayoutrequirementsarenecessary
forsuccessfulimplementationoftheSC1186PWM
rrentsswitchingat140kHzarepre-
sentintheapplicationandtheireffectongroundplane
voltagedifferentialsmustbeunderstoodandmini-
mized.
1).Thehighpowerpartsofthecircuitshouldbelaid
dplaneshouldbeused,thenumber
andpositionofgroundplaneinterruptionsshouldbe
suchastonotunnecessarilycompromisegroundplane
edorsemi-isolatedareasoftheground
planemaybedeliberatelyintroducedtoconstrain
groundcurrentstoparticularareas,forexamplethe
inputcapacitorandbottomFETground.
2).TheloopformedbytheInputCapacitor(s)(Cin),the
TopFET(Q1)andtheBottomFET(Q2)mustbekept
opcontainsallthehigh
current,tionsshould
beaswideandasshortaspossibletominimizeloop
zingthisloopareawilla)reduce
EMI,b)lowergroundinjectioncurrents,resultingin
electrically“cleaner”groundsfortherestofthesystem
a生僻却美到爆的词牌名 ndc)minimizesourceringing,resultinginmorereli-
ablegateswitchingsignals.
3).TheconnectionbetweenthejunctionofQ1,Q2and
theoutputinductorshouldbeawidetraceorcopper
his
connectionhasfastvoltagetransitions,keepingthis
nection
betweentheoutputinductorandthesenseresistor
shouldbeawidetraceorcopperarea,thereareno
fastvoltageorcurrenttransitionsinthisconnection
andlengthisnotsoimportant,howeveraddingunnec-
essaryimpedancewillreduceefficiency.
Vout
12VIN
3.3VVoLin1
VoLin2
5V
4uH
5mOhm
+
Cout
+
Cin
10
Q2
0.1uF
Q3
+
CoutLin1
2.32k
Q4
+
CoutLin2
1.00k
+
CinLin
SC1186
AGND
1
VCC
5
REF
6
LDOEN
7
CS-
8
CS+
9
PGNDH
10
DH
11
BSTH
15
EN
16
VOSENSE
17
VID4
18
VID3
19
VID2
20
VID1
21
VID0
22
DL
13
PGNDL
12
BSTL
14
GATE2
24
GATE1
2
LDOV
23
LDOS1
3
LDOS2
4Q1
0.1uF
Heavylinesindicate
highcurrentpaths.
LayoutdiagramfortheSC1186
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9
Vout
5V
+
+
4)TheOutputCapacitor(s)(Cout)shouldbelocated
asclosetotheloadaspossible,fasttransientload
currentsaresuppliedbyCoutonly,andconnections
betweenCoutandtheloadmustbeshort,widecop-
perareastominimizeinductanceandresistance.
5)TheSC1186isbestplacedoveraquietground
planearea,avoidpulsecurrentsintheCin,Q1,Q2
ndPGNDLshould
bereturnedtothegroundplaneclosetothepackage.
TheAGNDpinshouldbeconnectedtotheground
sideof(oneof)theoutputcapacitor(s).Ifthisisnot
possible,theAGNDpinmaybeconnectedtothe
groundpathbetweentheOutputCapacitor(s)andthe
Cin,Q1,ocircumstancesshould
AGNDbereturnedtoagroundinsidetheCin,Q1,Q2
loop.
6)VccfortheSC1186shouldbesuppliedfromthe
5Vsupplythrougha10
Ω
resistor,theVccpinshould
bedecoupleddirectlytoAGNDbya0.1
Fceramic
capacitor,tracelengthsshouldbeasshortaspossi-
ble.
7)TheCurrentSenseresistorandthedivideracross
itshouldformassmallaloopaspossible,thetraces
runningbacktoCS+andCS-ontheSC1186should
0.1
Fca-
pacitorshouldbemountedasclosetotheCS+and
CS-pinsaspossible.
8)Ideally,thegroundsforthetwoLDOsections
shouldbereturnedtothegroundsideof(oneof)the
outputcapacitor(s).
Currentsinvariouspartsofthepowersection
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10
COMPONENTSELECTION
SWITCHINGSECTION
OUTPUTCAPACITORS-Selectionbeginswiththe
eoffasttransientload
currentrequirementsinmodernmicroprocessorcore
supplies,theoutputcapacitorsmustsupplyalltransient
loadcurrentrequirementsuntilthecurrentintheoutput
capacitor
maximumESRcanbesimplycalculatedfrom:
stepcurrentTransientI
excursionvoltagetransientMaximumV
Where
I
V
R
t
t
t
t
ESR
=
=
≤
EachCapacitorTotal
TechnologyC
(F)
ESR
(m
Ω
)
Qty.
Rqd.
C
(F)
ESR
(m
Ω
)
LowESRTantalum33
OS-CON3302539908.3
LowESRAluminum15.8
()OIN
t
ESRVV
I
CR
L
−≤
OSC
IN
LfL4
V
I
RIPPLE⋅⋅
=
IN
O
)on(DS
2
OCOND
V
V
cycleduty=
where
RIP
≈
⋅⋅=
2
INOSW
10VIP−⋅⋅=
4
f)tt(VI
POSCfrINO
SW
⋅+⋅⋅
=
OSCINRRRR
fVQP
⋅⋅=
Forexample,tomeeta100mVtransientlimitwitha
10Aloadstep,theoutputcapacitorESRmustbeless
than10m
Ω
.TomeetthiskindofESRlevel,thereare
threeavailablecapacitortechnologies.
Thechoiceofwhichtouseissimplyacost/perfor-
manceissue,withLowESRAluminumbeingthe
cheapest,buttakingupthemostspace.
INDUCTOR-Havingdecidedonasuitabletypeand
valueofoutputcapacitor,themaximumallowable
geanin-
ductorwillproduceaslowcurrentramprateandwill
causetheoutputcapacitortosupplymoreofthetran-
sientloadcurrentforlonger-leadingtoanoutputvolt-
agesagbelowtheESRexcursioncalculatedabove.
Themaximuminductorvaluemaybecalculatedfrom:
Thecalculatedmaximuminductorvalueassumes100%
dutycycle,ng
aninductorvalueof50to75%ofthecalculatedmaxi-
mumwillguaranteethattheinductorcurrentwillramp
fastenoughtoreducethevoltagedroppedacrossthe
ESRatafasterratethanthecapacitorsags,henceen-
suringagoodrecoveryfromtransientwithnoadditional
excursions.
Wemustalsobeconcernedwithripplecurrentinthe
outputinductorandageneralruleofthumbhasbeento
allow10%ofmaximumoutputcurrentasripplecurrent.
Notethatmostoftheoutputvoltagerippleisproduced
bytheinductorripplecurrentflowingintheoutputca-
currentcanbecalculatedfrom:
Ripplecurrentallowancewilldefinetheminimumper-
mittedinductorvalue.
POWERFETS-TheFETsarechosenbasedonsev-
eralcriteriawithprobablythemostimportantbeing
powerdissipationandpowerhandlingcapability.
TOPFET-ThepowerdissipationinthetopFETisa
combinationofconductionlosses,switchinglossesand
bottomFETbodydioderecoverylosses.
a)Conductionlossesaresimplycalculatedas:
b)Switchinglossescanbeestimatedbyassuminga
switchingtime,ifweassume100nsthen:
ormoregenerally,
c)Bodydioderecoverylossesaremoredifficulttoesti-
mate,buttoafirstapproximation,itisreasonabletoas-
sumethatthestoredchargeonthebottomFETbody
diodewillbemovedthroughthetopFETasitstartsto
ultingpowerdissipationinthetopFET
willbe:
Toafirstorderapproximation,itisconvenienttoonly
considerconductionlossestodete人教版七年级下册语文目录 rmineFETsuitability.
Fora5Vin;2.8Voutat14.2Arequirement,typicalFET
losseswouldbe:
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)1(RIP
)on(DS
2
OCOND
−⋅⋅=
FETtype
R
DS(on)
(m
Ω
)
P
D
(W)Package
IRL34025151.69D2PAK
IRL220310.51.19D2PAK
Si4410202.26SO-8
FETtype
R
DS(on)
(m
Ω
)
P
D
(W)Package
IRL34025151.33D2PAK
IRL220310.50.93D2PAK
Si4410201.77SO-8
BOTTOMFET-BottomFETlossesarealmostentirely
ydiodeisforcedintocon-
ductionatthebeginningandendofthebottomswitch
conductionperiod,sowhentheFETturnsonandoff,
thereisverylittlevoltageacrossit,resultinginlow
tionlossesfortheFETcanbe
determinedby:
Fortheexampleabove:
Eachofthepackagetypeshasacharacteristicthermal
impedance,fortheTO-220package,thermal
impedanceismostlydeterminedbytheheatsinkused.
ForthesurfacemountpackagesondoublesidedFR4,2
ozprintedcircuitboardmaterial,thermalimpedancesof
40oC/WfortheD2PAKand80oC/WfortheSO-8are
respondingtemperaturerise
isdetailedbelow:
Temperaturerise(oC)
FETtypeTopFETBottomFET
IRL3402567.653.2
IRL220347.637.2
Si4410180.8141.6
ItisapparentthatsingleSO-8Si4410arenotadequate
forthisapplication,butbyusingparallelpairsineachpo-
sition,powerdissipationwillbeapproximatelyhalvedand
temperaturerisereducedbyafactorof4.
INPUTCAPACITORS-sincetheRMSripplecurrent
intheinputcapacitorsmaybeashighas50%ofthe
outputcurrent,suitablecapacitorsmustbechosenac-
,duringfastloadtransients,theremay
berestrictionsoninputdi/estrictionsrequire
useableenergystoragewithintheconvertercircuitry,
eitherasextraoutputcapacitanceor,moreusually,
nglowESRinput
capacitorswillhelpmaximizerippleratingforagiven
size.
SHORTCIRCUITPROTECTION-LINEARS
TheShortcircuitfeatureonthelinearcontrollersis
implementedbyusingtheRds(on)
outputcurrentincreases,theregulationloopmaintains
theoutputvoltagebyturningtheFETonmoreand
ally,astheRds(on)limitisreached,the
FETwillbeunablytoturnonmorefully,andoutput
eoutputvoltagefalls
toapproximately50%ofnominal,theLDOcontroller
islatchedoff,ust
becycledtoresetthelatch.
Topreventfalselatchingduetocapacitorinrushcur-
rentsorlowsupplyrails,thecurrentlimitlatchisini-
abledatapresettime(nominally
2mS)afterboththeLDOVandLDOENrailsrise
abovetheirlockoutpoints.
Tobemosteffective,thelinearFETRds(on)should
notbeselectedartificiallylow,theFETshouldbecho-
sensothat,atmaximumrequiredcurrent,itisalmost
fullyturnedon
If,forexample,alinearsupplyof1.5Vat4Aisre-
qui雨字开头的成语 redfroma3.3V5%rail,maxallowableRds(on)
wouldbe.
Rds(on)max=(0.95*3.3-1.5)/4
≈
400m
Ω
Toallowfortemperatureeffects200m
Ω
wouldbea
suitableroomtemperaturemaximum,allowingapeak
shortcircuitcurrentofapproximately15Aforashort
timebeforeshutdown.
Using1.5XRoomtempR
DS(ON)
toallowfortemperature
rise.
元器件交易网
PROGRAMMABLESYNCHRONOUSDC/DC
CONVERTER,DUALLOWDROPOUT
REGULATORCONTROLLER
1999SEMTECHCORP.
PRELIMINARY-December2,1999
652MITCHELLROADNEWBURYPARKCA91320
SC1186
12
OUTLINEDRAWING
JEDECMS-013AD
B17104B
ECN99-6009-22-99
ECN99-71912-2-99
元器件交易网
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