580EXII Posibile Probleme

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PreliminaryResearchReportonCanon580EXIIFlashFailuresByJimClark&TimAmbrose,ResearchandDevelopment

LPADesignBackground:SincethelaunchofitsPocketWizardMiniTT1andFlexTT5modelsinearly2009,LPADesign(A.K.A.

PocketWizard)hasbeenreceivingperiodiccallsandreportsfromcustomerswhoareusingtheirCanon

580EXIIflasheswiththePocketWizardControlTLradiosandexpressingconcernthatperhapstheirflash

mayhavebeendamagedbyusingaPocketWizardradiotriggerwithit.

Asofthetimeofthisreport(Jan,2011),thereareabout120140PocketWizardcustomerswhohave

reportedhavingoneormore580EXIIflashesdamagedwithcommonsymptomsoverthepast18+

months.

Ifthefailuremodewasrelatedtoourproduct,thiswouldworkouttolessthan0.5%ofour

MiniTT1/FlexTT5radio

units

which

were

connected

to

aflash

that

failed

and

less

than

1%

of

the

580EX

II

flashesthatwereconnectedweredamaged.

LPADesignhasconductedaseriousindepthinvestigationforseveralmonthsaswecontinuetocollect

dataandevidenceofthespecificsofthefailuremode. Inadditionwehavejuststartedtheoutside

researchassistanceofanalyticalchemistryprofessorGiuseppePetrucciattheUniversityofVermont.

Research:Thesymptomofthefailureisthatthe580EXIIwillnolongeroutputcontrolledamountsoflight. Itwill

onlyoutputfullpowerdumps. Thisfullpowerdumpwillhappenevenonapreflash,thereforeleaving

nostoredenergywithinthecapacitorleftforamainflashexposure.

ThetestingquicklyrevealedthatanIGBT(transistor)withintheflashisdamaged. Thispartismadeby

Renesas(part#RJP4301).

TheIGBTisusedtoturnofftheflowofcurrentthroughtheflashtubewhenthedesiredamountoflight

hasbeenreached. ThisIGBTisalsousedtocontrol(modulate)thebrightnessofthelightwheninHSS

(HighSpeedSync)withthehelpofafiberopticcablefeedingalightsensorwithinthemainbody.

AlthoughLPADesignhasbeenabletoidentifythesymptomoftheproblem,LPADesignhasnotbeen

abletotracethecauseoftheproblemtoourPocketWizardproductsandwehavenoknowledgeofthe

incidenceratesofthisproblemarisingindependentlywithoutPocketWizard,i.e.somenumberof580EX

IIflasheslikelyfailwithoutPocketWizardControlTLradiosinteractingwiththem.Wereceivedreports

ofthis

IGBT

failure

in

all

spectrums

of

use.

It

spans

multiple

different

Canon

camera

models,

below

XSyncandaboveinHSS(moreofteninHSS),TTLormanualmodesandonanyversionoffirmwarethat

thePocketWizardMiniTT1andFlexTT5havehadinpublicrelease. Evenbrandnewflashescouldfail.

Wehaveruledoutheatbuildupasacausesinceseveralhavefailedwithinthefirstdozenshotsafter

beingpulledoutofthecamerabag. Thisisallbasedonverbaldescriptionsfromcustomers.

ItalsohasfailedasmanytimeswithaPocketWizardAC5RFSoftShieldasithasfailedwithoutusingthe

AC5. SothereappearstobenochangeinoccurrencewhenusingtheAC5orAC7.

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Wepurch

otherco

MostsigOnecom

replacem

Theseco

discharge

Repaired

periods

Soitbeca

Eventuall

andsoot

place.

Replacem

failwitho

Belowar

asedmanyo

moneleme

ificantobseontheme

ent.

dcommont

fromoneor

unitsthatha

henuseddir

mecleartha

wefoundt

builduparou

entofthefl

rwithouta

exampleso

fthefailedfl

tsbetween

vations:asthatALLf

hemewasth

moreendso

eonlytheI

ectlyonaCa

ttheIGBTw

attheflash

ndthe

ends

shheadssol

ocketWizard

the580EXII

ashesfrome

heunitstha

ailedflashu

atALLfailed

ftheflashtu

BTreplaced

oncamera

snttheonly

ead(tube/r

fthe

flash

tu

edthefailur

radio.

flashheads

ndusersso

failed.

itshavehad

unitshavevi

betotheme

willfrequen

ithoutaPo

failurecom

flector)was

be.Sparks

a

eproblems

hatwereca

ecouldtake

theIGBTda

iblesignsof

talreflector.

lyfailagain

ketWizardr

onentwithi

alsobadand

ndelectrical

ndtheflash

singIGBTfai

themapart

agedandn

electricalarc

ithinrelativ

dioinvolved

thesystem.

showedvisi

arcingwere

scouldnol

lurestorepe

ndstudyth

eded

ing/electric

elyshorttim

.

lesignsofa

pparentlyt

ngerbemad

at

l

sh

king

eto

7/22/2019 580EXII Posibile Probleme

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Figure1:

oxidizatio

Figure2:

possible

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housingi

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Figure4:

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ElectricalWecaptu

Forrefer

theIGBT

Belowis

Figure6:

AnalysisofFredfailuree

nce,IGBTcu

mitterlead.

nexampleo

Inthemiddl

ailureModeentsaswell

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ofaHighSp

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th

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Figure7:

sparkjum

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flectorandt

ctricalsignal

henintothe

. Notethat

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e

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Figure8:

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Figure10

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