Crane Aerospace & Electronics Power Solutions
MCH/MGH Single and Dual DC-DC Converters
28 Volt input – 1.5 Watt
Features
smꢀll fooꢁpꢂinꢁ, 0.79 in2 (5.1 cm2) - MCH
sꢃꢂfꢀcꢄ moꢃnꢁ pꢀckꢀgꢄ - MGH
•ꢀ Operatingꢀtemperatureꢀ-55°Cꢀtoꢀ+125°C
•ꢀ Inputꢀvoltageꢀ12ꢀtoꢀ50ꢀVDC
•ꢀ Transientꢀprotectionꢀ80ꢀVꢀforꢀupꢀtoꢀ120ꢀmsꢀ
-ꢀ 70ꢀVꢀforꢀ15ꢀVꢀsingleꢀandꢀdualꢀmodels
•ꢀ Fullyꢀisolated,ꢀmagneticꢀfeedback
•ꢀ Fixedꢀfrequencyꢀswitching
•ꢀ Inhibitꢀfunction
MODeꢅs
VDC Output
•ꢀ Shortꢀcircuitꢀprotection
SINGLE
DUAL
±5
•ꢀ Undervoltageꢀlockout
5
•ꢀ Upꢀtoꢀ79%ꢀefficiency
12
15
±12
±15
DesCrIPtION
Dualꢀmodelsꢀregulateꢀtheꢀnegativeꢀoutputꢀwithꢀmagneticꢀcouplingꢀ
toꢀtheꢀpositiveꢀoutput.ꢀUpꢀtoꢀ80%ꢀofꢀtheꢀtotalꢀloadꢀmayꢀbeꢀonꢀ
oneꢀoutputꢀprovidingꢀthatꢀtheꢀotherꢀoutputꢀcarriesꢀaꢀminimumꢀofꢀ
20%ꢀofꢀtheꢀtotalꢀload.ꢀTheꢀdualꢀmodelsꢀcanꢀbeꢀusedꢀatꢀdoubleꢀ
theꢀoutputꢀvoltageꢀbyꢀconnectingꢀtheꢀloadꢀbetweenꢀpositiveꢀandꢀ
negativeꢀoutputs,ꢀleavingꢀtheꢀcommonꢀunconnected.ꢀꢀ
TheꢀInterpoint™ꢀMCHꢀꢀSeries™ꢀandꢀMGHꢀSeries™ꢀofꢀdc-dcꢀ
convertersꢀdeliverꢀ1.5ꢀwattsꢀofꢀoutputꢀpowerꢀwhileꢀsavingꢀ
significantꢀboardꢀrealꢀestate.ꢀTheꢀwideꢀinputꢀvoltageꢀrangeꢀofꢀ12ꢀ
toꢀ50ꢀVDCꢀacceptsꢀtheꢀvaryingꢀvoltagesꢀofꢀmilitary,ꢀaerospace,ꢀorꢀ
spaceꢀbusꢀpowerꢀandꢀtightlyꢀregulatesꢀoutputꢀvoltagesꢀtoꢀprotectꢀ
downstreamꢀcomponents.ꢀTransientꢀprotectionꢀofꢀ80ꢀvoltsꢀforꢀupꢀ
toꢀ120ꢀmillisecondsꢀexceedsꢀtheꢀrequirementsꢀofꢀMIL-STD-704Aꢀ
forꢀtheꢀ5ꢀandꢀ12ꢀvoltꢀsingleꢀmodelsꢀandꢀtheꢀ12ꢀvoltꢀdualꢀmodel.ꢀ
Theꢀ15ꢀvoltꢀsingleꢀandꢀdualꢀconvertersꢀwillꢀwithstandꢀtransientsꢀofꢀ
upꢀtoꢀ70ꢀvoltsꢀforꢀupꢀtoꢀ120ꢀmilliseconds.
(ex:ꢀMCH2805Dꢀcanꢀbeꢀusedꢀasꢀaꢀ10ꢀVDCꢀoutput.)
inhibit FunCtion
MCHꢀandꢀMGHꢀconvertersꢀprovideꢀanꢀinhibitꢀterminalꢀthatꢀcanꢀbeꢀ
usedꢀtoꢀdisableꢀinternalꢀswitching,ꢀresultingꢀinꢀnoꢀoutputꢀvoltageꢀ
andꢀanꢀinputꢀcurrentꢀasꢀlowꢀasꢀ2.3ꢀmA.ꢀTheꢀconverterꢀisꢀinhibitedꢀ
whenꢀtheꢀinhibitꢀpinꢀisꢀpulledꢀbelowꢀ0.8ꢀVꢀandꢀenabledꢀwhenꢀitsꢀ
inhibitꢀpinꢀisꢀleftꢀfloating.ꢀAnꢀexternalꢀinhibitꢀinterfaceꢀshouldꢀbeꢀ
capableꢀofꢀpullingꢀtheꢀconverter’sꢀinhibitꢀpinꢀbelowꢀ0.8ꢀVꢀwhileꢀ
sinkingꢀtheꢀmaximumꢀinhibitꢀcurrentꢀandꢀalsoꢀallowingꢀtheꢀinhibitꢀ
pinꢀtoꢀfloatꢀhighꢀtoꢀenableꢀtheꢀconverter.ꢀAꢀvoltageꢀshouldꢀnotꢀbeꢀ
appliedꢀtoꢀtheꢀinhibitꢀpin.ꢀTheꢀopenꢀcircuitꢀvoltageꢀpresentꢀonꢀtheꢀ
inhibitꢀpinꢀisꢀ7ꢀtoꢀ12ꢀV.ꢀ
Theꢀconvertersꢀareꢀofferedꢀwithꢀstandardꢀscreening,ꢀ“ES”ꢀ
screening,ꢀorꢀfullyꢀcompliantꢀtoꢀ“883”ꢀMIL-PRF-38534ꢀClassꢀHꢀ
screening.ꢀSeeꢀ“Tableꢀ11:ꢀElementꢀEvaluation”ꢀonꢀpageꢀ12ꢀandꢀ
“Tableꢀ12:ꢀEnvironmentalꢀScreening”ꢀonꢀpageꢀ13.ꢀStandardꢀ
microcircuitꢀdrawingsꢀ(SMD)ꢀareꢀavailable.ꢀSeeꢀ“Tableꢀ5:ꢀ
MCHꢀSMDꢀNumbers”ꢀonꢀpageꢀ4ꢀandꢀ“Tableꢀ6:ꢀMGHꢀSMDꢀ
Numbers”ꢀonꢀpageꢀ4.
Converter Design
MCHꢀSeriesꢀandꢀMGHꢀSeriesꢀofꢀdc-dcꢀconvertersꢀincorporateꢀaꢀ
continuousꢀflybackꢀtopologyꢀwithꢀaꢀconstantꢀswitchingꢀfrequencyꢀ
ofꢀapproximatelyꢀ370ꢀkHz.ꢀꢀCurrent-modeꢀpulseꢀwidthꢀmodulationꢀ
(PWM)ꢀprovidesꢀoutputꢀvoltageꢀregulation.ꢀOutputꢀerrorꢀvoltageꢀ
isꢀmagneticallyꢀfedꢀbackꢀtoꢀtheꢀinputꢀsideꢀofꢀtheꢀPWMꢀtoꢀregulateꢀ
outputꢀvoltage.ꢀRegulationꢀisꢀalsoꢀaffectedꢀbyꢀtheꢀload;ꢀreferꢀꢀ
toꢀtheꢀElectricalꢀCharacteristicsꢀTableꢀ9ꢀonꢀpageꢀ6ꢀandꢀ
Tableꢀ10ꢀonꢀpageꢀ7.
ProteCtion Features
Undervoltageꢀlockoutꢀpreventsꢀtheꢀconvertersꢀfromꢀoperatingꢀ
belowꢀapproximatelyꢀ8ꢀVDCꢀinputꢀvoltageꢀtoꢀkeepꢀsystemꢀ
currentꢀlevelsꢀsmooth,ꢀespeciallyꢀduringꢀinitializationꢀorꢀre-startꢀ
operations.ꢀAllꢀmodelsꢀincludeꢀaꢀsoft-startꢀfunctionꢀtoꢀpreventꢀ
largeꢀcurrentꢀdrawꢀandꢀminimizeꢀovershoot.ꢀTheꢀconvertersꢀalsoꢀ
provideꢀshortꢀcircuitꢀprotectionꢀbyꢀrestrictingꢀtheꢀcurrent.ꢀ
ꢀ
MiL-stD-461
UseꢀtheꢀInterpointꢀFMSA-461ꢀ(down-leaded)ꢀorꢀFMGA-461ꢀ
(surfaceꢀmount,ꢀside-leaded)ꢀEMIꢀfiltersꢀtoꢀpassꢀtheꢀCE03ꢀ
requirementsꢀofꢀMIL-STD-461C.
Crane Aerospace & Electronics
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Power Solutions – Interpoint Products
10301 Willows Rd. NE, Redmond, WA 98052
+1.425.882.3100 • power@crane-eg.com
www.craneae.com/interpoint
MCH_MGHꢀRevꢀABꢀ-ꢀ2013.05.31