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PKJ4000EPIEN/LZT146025R8AEricssonPowerModules,June2007
Operating Information
Input Voltage
Theinputvoltagerange36…75Vdcmeetstherequirements
oftheEuropeanTelecomStandardETS300132-2for
normalinputvoltagerangein–48Vand–60VDCsystems,
-40.5…-57.0Vand–50.0…-72Vrespectively.Atinput
voltagesexceeding75V,thepowerlosswillbehigherthan
atnormalinputvoltageandTPcbmustbelimitedtoabsolute
max+125°C.Theabsolutemaximumcontinuousinput
voltageis80Vdc.
Turn-Off Input Voltage
ThePKJ4000ESeriesDC/DCconvertersmonitortheinput
voltageandwillturnonandturnoffatpredeterminedlevels.
Theminimumhysteresisbetweenturnonandturnoffinput
voltageis1Vwheretheturnoninputvoltageisthehighest.
Output Voltage Adjust (Vadj)
AllPKJ4000ESeriesDC/DCconvertershaveanOutput
Voltageadjustpin(Vadj).Thispincanbeusedtoadjustthe
outputvoltageaboveorbelowOutputvoltageinitialsetting.
Whenincreasingtheoutputvoltage,thevoltageattheoutput
pins(includinganyremotesenseoffset)mustbekeptbelow
theovervoltagetrippoint,topreventtheconverterfrom
shutdown.Alsonotethatatincreasedoutputvoltagesthe
maximumpowerratingoftheconverterremainsthesame,
andtheoutputcurrentcapabilitywilldecreasecorrespond-
ingly.Todecreasetheoutputvoltagetheresistorshouldbe
connectedbetweenVadjpinand–Sensepin.Toincrease
thevoltagetheresistorshouldbeconnectedbetweenVadj
pinand+Sensepin.TheresistorvalueoftheOutputvoltage
adjustfunctionisaccordingtoinformationgivenunderthe
outputsection.
Remote Control (RC)
ThePKJ4000ESeriesDC/DC
convertershavearemotecontrol
functionreferencedtotheprimary
side(-In),withnegativeandpositive
logicoptionsavailable.TheRC
functionallowstheconvertertobe
turnedon/offbyanexternaldevice
likeasemiconductorormechanical
switch.TheRCpinhasaninternal
pullupresistorto+In.Theneededmaximumsinkcurrent
is1mA.WhentheRCpinisleftopen,thevoltagegenerated
ontheRCpinis3.5-6.0V.Themaximumallowableleakage
currentoftheswitchis50A.
Thestandardconverterisprovidedwith“negativelogic”
remotecontrolandtheconverterwillbeoffuntiltheRC
pinisconnectedtothe-In.Toturnontheconverterthe
voltagebetweenRCpinand-Inshouldbelessthan1V.
ToturnofftheconvertertheRCpinshouldbeleftopen,or
connectedtoavoltagehigherthan4Vreferencedto-In.In
situationswhereitisdesiredtohavetheconvertertopower
upautomaticallywithouttheneedforcontrolsignalsora
switch,theRCpincanbewireddirectlyto-In.
Thesecondoptionis“positivelogic”remotecontrol,which
canbeorderedbyaddingthesuffix“P”totheendofthe
partnumber.Theconverterwillturnonwhentheinput
voltageisappliedwiththeRCpinopen.Turnoffisachieved
byconnectingtheRCpintothe-In.Toensuresafeturn
offthevoltagedifferencebetweenRCpinandthe-Inpin
shallbelessthan1V.Theconverterwillrestartautomatically
whenthisconnectionisopened.
AllPKJ4000ESeriesDC/DCconvertershaveremotesense
thatcanbeusedtocompensateformoderateamountsofre-
sistanceinthedistributionsystemandallowforvoltagereg-
ulationattheloadorotherselectedpoint.Theremotesense
lineswillcarryverylittlecurrentanddonotneedalarge
crosssectionalarea.However,thesenselinesonthePCB
shouldbelocatedclosetoagroundtraceorgroundplane.
Inadiscretewiringsituation,theuseoftwistedpairwires
orothertechniquetoreducenoisesusceptibilityishighly
recommended.Theremotesensecircuitrywillcompensate
forupto10%voltagedropbetweenthesensevoltageand
thevoltageattheoutputpins.Theoutputvoltageandthe
remotesensevoltageoffsetmustbelessthantheminimum
overvoltagetrippoint.Iftheremotesenseisnotneededthe
–Senseshouldbeconnectedto–Outand+Senseshouldbe
connectedto+Out.
Remote Sense
Circuitconfigurationforoutputvoltageadjust
+Out
-Out
+Sense
Vadj
-Sense
Load
Radj
Decrease
Load
Increase
+Out
-Out
+Sense
Vadj
-Sense
Circuitconfiguration
forRCfunction
+In
RC
-In