Operating Information
AꢀcombinationꢀofꢀlowꢀESRꢀandꢀoutputꢀcapacitanceꢀ
exceedingꢀ8ꢀmFꢀcanꢀcauseꢀtheꢀregulatorꢀintoꢀoverꢀcurrentꢀ
protectionꢀmodeꢀ(hick-up)ꢀdueꢀtoꢀhighꢀstartꢀupꢀcurrent.ꢀTheꢀ
outputꢀfilterꢀmustꢀthereforeꢀbeꢀdesignedꢀwithoutꢀexceedingꢀ
theꢀaboveꢀstatedꢀcapacitanceꢀlevelsꢀifꢀtheꢀESRꢀisꢀlowerꢀthanꢀ
30-40ꢀmΩ.
Parallel Operation
TheꢀPMBꢀ4000ꢀSeriesꢀDC/DCꢀregulatorsꢀcanꢀbeꢀconnectedꢀinꢀ
parallelꢀwithꢀaꢀcommonꢀinput.ꢀParallelingꢀisꢀaccomplishedꢀbyꢀ
connectingꢀtheꢀoutputꢀvoltageꢀpinsꢀdirectlyꢀandꢀusingꢀaꢀloadꢀ
sharingꢀdeviceꢀonꢀtheꢀinput.ꢀLayoutꢀconsiderationsꢀshouldꢀbeꢀ
madeꢀtoꢀavoidꢀloadꢀimbalance.ꢀForꢀmoreꢀdetailsꢀonꢀparallel-
ing,ꢀpleaseꢀconsultꢀyourꢀlocalꢀapplicationsꢀsupport.ꢀ
Input Undervoltage Lockout
TheꢀPMBꢀ4000ꢀSeriesꢀDC/DCꢀregulatorsꢀareꢀequippedꢀwithꢀaꢀ
lockoutꢀfunctionꢀforꢀlowꢀinputꢀvoltage.Whenꢀtheꢀinputꢀvoltageꢀ
isꢀbelowꢀtheꢀundervoltageꢀlockoutꢀlimitꢀofꢀtheꢀregulatorꢀitꢀwillꢀ
shutꢀoff.ꢀWhenꢀtheꢀinputꢀvoltageꢀincreasesꢀaboveꢀtheꢀlockoutꢀ
levelꢀtheꢀregulatorꢀwillꢀturnꢀon.ꢀ
ꢀꢄ
ꢀꢀꢀꢀꢀꢀEN/LZTꢀ146ꢀ049ꢀR4Aꢀ©EricssonꢀPowerꢀModules,ꢀMarchꢀ2007
PMBꢀ4518TꢀWPꢀDatasheet
ERICSSON [ ERICSSON ]
