www.德州仪器.com
FUNCTIONALDESCRIPTION
OVERVIEW
POWERSTAGE
OSCILLATORANDWATCHDOG
构建
THERMALSHUTDOWN
同步
DCP
02
V
输出 1
V
供应
V
S
0V
V + v
输出 1 输出 2
同步
0V
COM
DCP
02
V
输出 2
V
S
0V
同步
0V
DCP02Series
SBVS011C–MARCH2000–REVISEDDECEMBER2005
Thisisduetothesmallvariationsinswitching
frequenciesbetweenthedc/dcconverters.
TheDCP02overcomesthisbyallowingdevicestobe
TheDCP02offersupto2Wofunregulatedoutput
synchronizedtooneanother.uptoeightdevicescan
powerfroma5v,12v,15v,or24vinputsourcewith
besynchronizedbyconnectingtheSYNCpins
atypicalefficiencyofupto89%.thisisachieved
一起,takingcaretominimizethecapacitanceof
throughhighlyintegratedpackagingtechnologyand
追踪.straycapacitance(>10pf)willhavethe
theimplementationofacustompowerstageand
effectofreducingtheswitchingfrequency,oreven
controlic.thecircuitdesignusesanadvanced
stoppingtheoscillatorcircuit.itisalsorecommended
bicmos/dmosprocess.
thatpowerandgroundlinesbestar-连接.
Itshouldbenotedthatifsynchronizeddevicesare
usedatstartup,alldeviceswilldrawmaximum
thedcp02usesapush-拉,中心-tappedtopology
currentsimultaneously.thiscancausetheinput
switchingat400khz(分隔-用-2froman800khz
voltagetodip,andifitdipsbelowtheminimuminput
振荡器).
电压(4.5v),thedevicesmaynotstartup.a2.2
µ
F
capacitorshouldbeconnectedclosetotheinputpins.
ifmorethaneightdevicesaretobesynchronized,它
Theonboard800kHzoscillatorgeneratesthe
isrecommendedthattheSYNCpinsbedrivenbyan
switchingfrequencyviaadivide-用-2circuit.这
externaldevice.detailsarecontainedinapplication
oscillatorcanbesynchronizedtootherDCP02
ReportSBAA035,
ExternalSynchronizationofthe
circuitsoranexternalsource,andisusedtominimize
dcp01/02seriesofdc/dcconverters
,availablefor
systemnoise.
downloadfromwww.德州仪器.com.
Awatchdogcircuitcheckstheoperationofthe
oscillatorcircuit.theoscillatorcanbestoppedby
pullingthesyncpinlow.theoutputpinswillbe
ThebasicconstructionoftheDCP02isthesameas
触发-陈述.thiswilloccurin2
µ
s.
standardics.thereisnosubstratewithinthemolded
包装.thedcp02isconstructedusinganic,
rectifierdiodes,andawoundmagnetictoroidona
thedcp02isprotectedbyathermal-关闭
引线框架.sincethereisnosolderwithinthe
电路.iftheon-chiptemperatureexceeds+150
°
c,
包装,thedcp02doesnotrequireanyspecial
thedevicewillshutdown.oncethetemperaturefalls
printedcircuitboard(pcb)assemblyprocessing.这个
below+150
°
c,normaloperationwillresume.
resultsinanisolateddc/dcconverterwithinherently
highreliability.
intheeventthatmorethanonedc/dcconverteris
neededonboard,beatfrequenciesandother
electricalinterferencecanbegenerated.
figure7.connectingthedcp02inseries
6