Iec 60747 5 6 2016

ratio b twe n the sp ctral radiant flu of wavelen th λ that is reflected by an o ject an the sp ctral radiant flu of wavelen th λ that is a sorb d by the o ject Note 1 to e try: Sp ctral

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CONTENTS

FOREWORD 7

1 Sco e 9

2 Normative referen es

9 3 Terms an definition 10 3.1 General terms an definition 10 3.2 Terms an definition relatin to the me s rement of the q antity of radiation 12 3.3 Terms an definition relatin to the me s rement of the photometric q antity 14 4 Absolute maximum ratin s 17 5 Electrical an o tical c aracteristic 18 6 Me s rin method 19 6.1 Basic req irements 19 6.1.1 Me s rin con ition 19 6.1.2 Me s rin in truments an eq ipment 2

6.1.3 Es ential req irements 21

6.1.4 General precaution 21 6.2 Forward voltage (V F ) me s rement 2

6.2.1 Purp se 2

6.2.2 Circ it diagram 2

6.2.3 Req irements 22 6.2.4 Me s rement proced re 2

6.2 5 Precaution to b o served 2

6.2.6 Sp cified con ition 24 6.3 Reverse voltage (V R ) me s rement 2

6.3.1 Purp se 2

6.3.3 Me s rement proced re 2

6.3.4 Precaution to b o served 2

6.3.5 Sp cified con ition 25 6.4 Dif erential resistan e (r f me s rement 2

6.4.1 Purp se 2

6.4.2 Circ it diagram 25 6.4.3 Req irements 25 6.4.4 Me s rement proced re 2

6.4.6 Sp cified con ition 26 6.5 Reverse c r ent (I R ) me s rement 2

6.5.1 Purp se 2

6.5.2 Circ it diagram 26 6.5.3 Provision 2

6.5.4 Me s rement proced re 27 6.5.5 Precaution to b o served 2

6.5.6 Sp cified con ition 27 6.6 Me s rement of ca acitan e b twe n terminals (C t 2

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6.6.2 Me s rement u in LCR meter 2

6.6.3 Me s rement u in AC brid e 2

6.7 Me s rement of ju ction temp rature an thermal resistan e (R th(j-X) 2

6.7.1 Purp se 2

6.7.2 Me s rement prin iple 2

6.8 Resp n e time me s rement 3

6.8.1 Purp se 3

6.8.3 Provision 3

6.8.6 Sp cified con ition 35 6.9 Freq en y resp n e an c t of freq en y (f c ) me s rement 3

6.9.1 Purp se 3

6.9.3 Provision 3

6.9.6 Sp cified con ition 38 6.10 Luminou flu (Φ V ) me s rement 3

6.10.1 Purp se 3

6.10.3 Me s rin circ it 38 6.10.4 Me s rement proced re 3

6.10.6 Me s rement con ition to b defined 4

6.1 Radiant p wer (Φ e ) me s rement 4

6.1 1 Purp se 4

6.1 2 Me s rement prin iple 4

6.1 3 Me s rin circ it 4

6.1 4 Me s rement proced re 41 6.1 5 Precaution to b o served 41

6.1 6 Me s rement con ition to b defined 4

6.12 Luminou inten ity (I V ) me s rement 4

6.12.1 Purp se 4

6.12.3 Me s rin circ it 4

6.12.4 Me s rement proced re 44 6.12.5 Precaution to b o served 4

6.13 Radiant inten ity (I e ) me s rement 4

6.13.1 Purp se 4

6.13.4 Me s rement proced re 45 6.13.5 Me s rement con ition to b defined 4

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6.14.1 Purp se 4

6.15 Emis ion sp ctrum distribution, p a emis ion wavelen th (λ ), an sp ctral half b n width (∆λ) me s rement 4

6.15.1 Purp se 4

6.16 Chromaticity me s rement 4

6.16.1 Purp se 4

6.16.5 Me s rin con ition to b defined 51

6.17 Directional c aracteristic me s rement 51

6.17.1 Purp se 51

6.18 Il uminan e (E V ) me s rement 5

6.18.1 Purp se 5

7 Items to b in icated on the p ck ge 5

8 Qualty evaluation 5

8.1 Clas ification of q al ty evaluation 5

8.1.1 General 5

8.1.2 Clas ification I 55 8.1.3 Clas ification I 55 8.1.4 Clas ification I I 55 8.1.5 Precaution to b o served 5

8.2 Qual ty evaluation test 6

8.2.1 General 6

8.2.2 Sp cimen 6

8.3 L t q al ty in p ction 60 8.3.1 General 6

8.3.2 Sp cimen 6

8.4 Periodical q al ty in p ction 6

8.4.1 General 6

8.4.2 Sp cimen 6

8.4.3 In p ction p riod 60 8.5 Easin of the lot q al ty in p ction stan ard 61

8.6 Periodical evaluation maintenan e tests 61

8.6.1 Test items an sp cimen 61

8.6.2 Test p riod 61

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8.8 Contin ou c r ent test 61

8.8.1 General 61

8.8.2 Initial me s rement 61

8.8.3 Test circ its 61

8.8.4 Test con ition 6

8.8.5 Post tre tment 6

8.8.6 Final me s rement 6

An ex A (normative) Stan ard luminou eficien y 6

An ex B (normative) How to o tain the self a sorption cor ection factor 6

B.1 Purp se 6

B.2 LED lg t sources for self a sorption me s rement 6

B.3 Method 6

An ex C (normative) How to o tain the colour cor ection factor 68 C.1 Purp se 6

C.2 Method 6

C.2.1 Luminou flu an luminou inten ity me s rement 6

C.2.2 Radiant p wer an radiant inten ity me s rement 6

An ex D (normative) Cal bration of the luminan e meter 7

D.1 Purp se 7

D.2 How to p rform the cal bration 7

An ex E (normative) Colour-matc in fu ction of the XYZ colour s stem 7

An ex F (normative) Sp ctral c romaticity co rdinates 7

An ex G (normative) Il uminometer cal bration 8

G.1 Purp se 8

G.2 How to p rform the cal bration 8

Bibl ogra h 8

Fig re 1 – Radiant inten ity 12 Fig re 2 – Radian e 13 Fig re 3 – Radiant exitan e 14 Fig re 4 – Ir adian e 14 Fig re 5 – Sp ctral luminou eficien y 15 Fig re 6 – Circ it diagram for V F me s rement 2

Fig re 7 – Circ it diagram for V F me s rement with a con tant voltage source an a c r ent lmitin resistor 2

Fig re 8 – Circ it diagram for V F me s rement u in an SMU 23 Fig re 9 – Circ it diagram for V R me s rement 2

Fig re 10 – circ it diagram for r f mes rement 2

Fig re 1 – Circ it diagram for I R me s rement 2

Fig re 12 – Circ it diagram for C t me s rement 2

Fig re 13 – Circ it diagram for C t me s rement 2

Fig re 14 – Circ it diagram for me s rement of c an e in V F 30 Fig re 15 – Waveform of c an e in V F 3

Fig re 16 – Tran ient c an e in thermal resistan e (double-logarithmic plots) 3

Fig re 17 – Circ it diagram for resp n e time me s rement 3

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Fig re 19 – Circ it diagram for f

c

me s rement 3

Fig re 2 – Circ it diagram for Φ V me s rement 3

Fig re 21 – circ it diagram for Φ e me s rement 41

Fig re 2 – Sc ematic diagram for I V me s rement 4

Fig re 2 – Circ it diagram for I V me s rement 4

Fig re 2 – circ it diagram for I e me s rement 4

Fig re 2 – Circ it diagram for L v me s rement 4

Fig re 2 – Circ it diagram for λ me s rement 4

Fig re 2 – Sc ematic diagram of ∆λ me s rement 4

Fig re 2 – Chromaticity 5

Fig re 3 – Circ it diagram for c romaticity me s rement 5

Fig re 31 – Directional c aracteristic (example 1) 5

Fig re 3 – Directional c aracteristic (example 2) 5

Fig re 3 – Circ it diagram for E v me s rement 5

Fig re 3 – Circ it diagram for contin ou c r ent test 6

Fig re B.1 – Sc ematic diagram for self a sorption me s rement 6

Fig re D.1 – Sc ematic diagrams for cal bration 71

Fig re G.1 – Sc ematic diagram for cal bration 8

Ta le 1 – Absolute maximum ratin s 18 Ta le 2 – Electrical an o tical c aracteristic 19 Ta le 3 – CIE averaged LED inten ity me s rements 4

Ta le 4 – Items for the s re nin test an their con ition (referen e) 5

Ta le 5 – Qual ty evaluation tests ( of 2) 5

Ta le 6 – L t q al ty in p ction 5

Ta le 7 – Periodical q al ty in p ction 5

Ta le A.1 – Definitive values of the sp ctral luminou eficien y fu ction for photo ic vision V(λ) ( of 3) 6

Ta le E.1 – Colour-matc in fu ction of the XYZ colour s stem ( of 5) 7

Ta le F.1 – Sp ctral c romaticity co rdinates ( of 5) 7

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INTERNATIONAL ELECTROTECHNICAL COMMISSION

Part 5-6: Optoelectronic devices – Light emit ing diodes

1) Th Intern tio al Ele trote h ic l Commis io (IEC) is a worldwid org nizatio for sta d rdizatio c mprisin

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this e d a d in a ditio to oth r a tivities, IEC p blsh s Intern tio al Sta d rds, Te h ic l Sp cific tio s,

Te h ic l Re orts, Pu lcly Av ia le Sp cific tio s (PAS) a d Guid s (h re fer refere to as “IEC

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in th su je t d alt with ma p rticip te in this pre aratory work Intern tio al g v rnme tal a d n

n-g v rnme tal org nizatio s laisin with th IEC also p rticip te in this pre aratio IEC c la orates closely

with th Intern tio al Org nizatio for Sta d rdizatio (ISO) in a c rd n e with c n itio s d termin d b

a re me t b twe n th two org nizatio s

2) Th formal d cisio s or a re me ts of IEC o te h ic l maters e pres , as n arly as p s ible, a intern tio al

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intereste IEC Natio al Commite s

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th later

5) IEC itself d es n t pro id a y atestatio of c nformity In e e d nt c rtific tio b dies pro id c nformity

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servic s c rie o t b in e e d nt c rtific tio b dies

6) Al users sh uld e sure th t th y h v th latest e itio of this p blc tio

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oth r d ma e of a y n ture wh tso v r, wh th r dire t or in ire t, or for c sts (in lu in le al fe s) a d

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Pu lc tio s

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in isp nsa le for th c re t a plc tio of this p blc tio

9) Ate tio is drawn to th p s ibi ty th t some of th eleme ts of this IEC Pu lc tio ma b th su je t of

p te t rig ts IEC sh l n t b h ld resp nsible for id ntifyin a y or al su h p te t rig ts

International Stan ard IEC 6 7 7-5-6 has b en pre ared by s bcommit e 4 E: Dis rete

semicon u tor devices, of IEC tec nical commite 4 : Semicon u tor devices

This first edition of IEC 6 7 7-5-6, together with IEC 6 7 7-5-4, IEC 6 7 7-5-5 an

IEC 6 7 7-5-7, can els an re laces IEC 6 7 7-5-1, IEC 6 7 7-5-2 an IEC 6 7 7-5-3,

publ s ed in 19 7, an their amen ments This edition con titutes a tec nical revision

This edition in lu es sig ificant tec nical c an es to the clau es for l g t emitin diodes in

IEC 6 7 7-5-1:19 7, IEC 6 7 7-5-2:19 7 an IEC 6 7 7-5-3:19 7, in lu in their

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The text of this stan ard is b sed on the fol owin doc ments:

Ful information on the votin for the a proval of this stan ard can b fou d in the re ort on

votin in icated in the a ove ta le

This publcation has b en drafed in ac ordan e with the ISO/IEC Directives, Part 2

A l st of al p rts in the IEC 6 7 7 series, publ s ed u der the general title Semico ductor

de ices, can b fou d on the IEC we site

The commit e has decided that the contents of this publ cation wi remain u c an ed u ti

the sta i ty date in icated on the IEC we site u der "htp:/ we store.iec.c " in the data

related to the sp cific publ cation At this date, the publ cation wi b

• reconfirmed,

• with rawn,

• re laced by a revised edition, or

• amen ed

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SEMICONDUCTOR DEVICES –

Part 5-6: Optoelectronic devices – Light emit ing diodes

This p rt of IEC 6 7 7 sp cifies the terminolog , the es ential ratin s an c aracteristic , the

me s rin method an the q al ty evaluation of l g t emit in diodes (LEDs) for general

in u trial a pl cation s c as sig als, control ers, sen ors, etc LEDs for l g tin a pl cation

e) I LED (infrared-emit in diode)

LEDs with a he t spre der or havin a terminal ge metry that p rforms the fu ction of a he t

spre der are within the s o e of this p rt of IEC 6 7 7

An integration of LEDs an controlge rs, integrated LED mod les, semi-integrated LED

mod les, integrated LED lamps or semi-integrated LED lamps, are out of the s o e of this

p rt of IEC 6 7 7

2 Normativ referenc s

The folowin doc ments, in whole or in p rt, are normatively referen ed in this doc ment an

are in isp n a le for its a pl cation For dated referen es, only the edition cited a pl es For

u dated referen es, the latest edition of the referen ed doc ment (in lu in an

IEC 6 7 9-6, Semico ductor de vice s – Me ch nical a d clmatc test meth ds – Part 6:

Stora e at high temp eratu re

IEC 6 7 9-10, Semico ductor de ices – Mech nical a d clmatc test meth ds – Part 10 :

Me ch nical sh ck

IEC 6 7 9-12, Semico ductor de ices – Mech nical a d clmatc te st meth ds – Part 12:

Vib rato , v riab le fre uency

IEC 6 7 9-14, Semico ductor de ice s – Me ch nical a d clmatc test meth ds – Part 14:

Trang 12

IEC 6 7 9-15 Semico ductor de ices – Mech nical a d clmatc te st meth ds – Part 15:

Re sistance to solderin temp ratu re forthrough-h le mounte d de ices

IEC 6 7 9-2 Semico ductor de ices – Mech nical a d clmatc te st meth ds – Part 20 :

Re sistance of plastc e ncap su lated SMDs to th comb in d efect of moistu re a d solderin

h at

Solderab il y

Ac elerated moisture resista ce – Unb iase d HAST

Temp erature cycln

Ac elerato , ste dy state

ISO 2 5 , Sampln p rocedures forinsp ecto b y atrib u tes

hol ow sphere whose internal s rface is a difu e reflector, as non-selective as p s ible

[SOURCE: IEC 6 0 0-8 5:19 7, 8 5-0 -2 , modified – The term "Ulbric t sphere" an the

note have b en removed

Trang 13

ratio b twe n the sp ctral radiant flu of wavelen th λ that is reflected by an o ject an the

sp ctral radiant flu of wavelen th λ that is a sorb d by the o ject

Note 1 to e try: Sp ctral refle ta c is also k own as th “sp ctral refle tio fa tor.”

3.1.9

spectral transmit ance

T(λ)

ratio b twe n the sp ctral radiant flu of wavelen th λ that is tran mited by an o ject an the

sp ctral radiant flu of wavelen th λ that is a sorb d by the o ject

Note 1 to e try: Sp ctral tra smita c is also k own as th “sp ctral tra smita c fa tor

3.1.10

spectral distribution

pro ortion of the q antum of radiation p r u it wavelen th in lu ed in the micro wavelen th

interval centre on wavelen th λ, whic is expres ed as a fu ction of wavelen th λ

Note 1 to e try: Sp ctral distrib tio is alsok own as th “sp ctrum distrib tio ”

3.1.1

spectral sensitivity

S(λ)

l g t sen itivity as a fu ction of wavelen th

Note 1 to e try: Th resp nse o tp t of th o tic l re eiv r for th ra ia t p wer (or lumin us flu ) in ut of

Trang 14

3.1.12

distribution temperature

temp rature of the Plan kian radiator whose relative sp ctral distribution S(λ) is the same or

ne rly the same as that of the radiation con idered in the sp ctral ran e of interest

Note 1 to e try: Th u it use is: K

le vin the source an pro agated in the element of sol d

an le dΩ containin the given direction, by the element of sol d an le

Note 1 to e try: For a ra iatio so rc th t is n t re ard d as a p int ra iatio so rc , th lmit v lu d termin d

b th v lu (whic is c lc late b dividin th ra ia t p wer th t is a sorb d b a smal are b th sold a gle

forme b th smal are toward a arbitrary p int o th ra iatio so rc ) wh n th dista c b twe n th

dΦ

eI

dΩ

So rc

IEC

Trang 15

[SOURCE: IEC 6 0 0-8 5:19 7, 8 5-01-3 , modified – The s mb l I has b en removed an

L

dcosdd

dΩ containin the given direction;

dA is the are of a section of that b am containin the given p int;

θ is the an le b twe n the normal to that section an the direction of the b am

e

dcos

d

π

ΩθL

dire tio s of th emite eleme tary b ams of sold a gle dΩ, a d θ is th a gle b twe n a y of th se b ams a d

th n rmal to th surfa e at th giv n p int

Trang 16

Note 1 to e try: An e uiv le t d finitio c uld b giv n as folows:Inte ral ta e o er th h misp ere visible

from th giv n p int, of th e pres io L

Note 1 to e try: Th re are two ty es of th se lamps: lumin us inte sity sta d rd lamps to whic th lumin us

inte sity v lu is a d d a d lumin us flu sta d rd lamps to whic th total flu v lu is a d d

Trang 17

Figure 5 – Spectral luminous ef icien y

Note 1 to e try: Th sp ctral lumin us eficie c for p oto ic visio was a re d at th CIE (Intern tio al

Commis io o I umin tio ) in 19 4 a d a o te b th CIPM (C omié Intern to al des Poids et Mesures –

Intern tio al Commite for Weig ts a d Me sures in En lsh) in 19 3 Th v lu s for sp ctral lumin us eficie c

were origin ly giv n for th wa ele gth ra g 3 0 nm to 7 0 nm at 10 nm interv ls In 19 2, n w v lu s were

a o te b th CIPM for th wa ele gth ra g 3 0nm to 8 0 nm at 1 nm interv ls

Note 2 to e try: Fig re 5 a d Ta le A.1 in An e A sh w th gra h a d th n meric sc eme for th sp ctral

lumin us eficie c , resp ctiv ly

3.3.3

maximum spectral luminous ef icienc

K

m

maximum value that is expres ed as the sp ctral con entration of the luminou flu in

wavelen th λ divided by the sp ctral con entration of the cor esp n in radiant p wer

by evaluatin the radiation ac ordin to its action up n

the CIE stan ard photometric o server

Note 1 to e try: This d finitio was a o te b th CIE in 19 8 Th relatio b twe n lumin us flu a d ra ia t

p wer is e pres e b th folowin formula

For p oto ic visio

( )

(λ) λ

λ

λΦ

d

dd

0e

[SOURCE: IEC 6 0 0-8 5:19 7, 8 5-01-2 , modified – The note has b en removed an p rt

of the definition has b en moved to notes to entry

Trang 18

Note 2 to e try: For a lg t so rc th t is n t re ard d as a p int lg t so rc , th lmit v lu d termin d b th

v lu (whic is c lc late b dividin th lumin us flu th t is a sorb d b a smal are b th sold a gle forme

b th smal are toward a arbitrary p int o th lg t so rc ) wh n th dista c b twe n th lg t so rc a d th

smal are b c mes lo g r, is use to c lc late th lumin us inte sity

Note 3 to e try: A lumin us inte sity of 1 c is d fin d as 1/6 × 10

is the luminou flu tran mit ed by an elementary b am p s in throu h the given p int

an pro agatin in the sold an le dΩ containin the given direction;

dA is the are of a section of that b am containin the given p int;

θ is the an le b twe n the normal to that section an the direction of the b am

Note 1 to e try: Th sp tial d finitio of lumin n e is sh wn in Fig re 2; h we er, symb l I sh uld b c a g d

Trang 19

dcos

d

π

ΩθL

dire tio s of th emite eleme tary b ams of sold a gle dΩ, a d θ is th a gle b twe n a y of th se b ams a d

Note 2 to e try: Th sp tial d finitio of lumin us e ita c is sh wn in Fig re 3; h we er, symb l Φ

vv

v

dcos

d

π

ΩθL

A

Φ

E

(dA: smal are )

Note 1 to e try: An e uiv le t d finitio c uld b giv n as folows: inte ral ta e o er th h misp ere visible

from th giv n p int, of th e pres io L

v

·c sθ·dΩ wh re L

v

is th lumin n e at th giv n p int in th v rio s

dire tio s of th in id nt eleme tary b ams of sold a gle dΩ, a d θ is th a gle b twe n a y of th se b ams a d

Note 2 to e try: Th sp tial d finitio of i umin n e is sh wn in Fig re 4; h we er, symb l Φ

Absolute maximum ratin s are s own in Ta le 1 They are sp cified at the ambient

temp rature or the referen e p int temp rature T

X

= (2 ± 3) °C, u les otherwise stated

These ratin s are a pl ca le to the five typ s of LED as des rib d in Clau e 1:

a) LED p ck ge;

b) LED flat i uminator;

c) LED n meric display an alpha-n meric display ;

d) LED dot matrix display;

Trang 20

Refere c p int X sh l b sele te a c rdin to th p rp se.

Refere c p int temp ratures ared scrib d as T

cfor c se, T

Sfor sold rin p int a dT

Electrical an o tical c aracteristic are s own in Ta le 2 They are sp cified at the ambient

temp rature or the referen e p int temp rature T

X

= (2 ± 3) °C, u les otherwise stated

These electrical an o tical c aracteristic are a pl ca le to the five typ s of LED as

Trang 21

Refere c p int X is sele te a c rdin to th p rp se.

Th rmal resista c s are d scrib d usin refere c p ints R

th(j-c)for c se, R

th(j-s)for sold r p int a d R

th(j-a)for

temp rature (T

X) of (2 ± 3) °C in a con ition of fre air

b) Humidity

When h midity con ition is not sp cified, relative h midity s al b b twe n 4 % an

c) Precaution

In some cases, me s rements c an e b cau e of he t generation in the test LED over

time In that case, it is neces ary to decide on the me s rement time, otherwise the

Trang 22

Thermal eq i brium may b con idered to have b en ac ieved if doubl n the time

b twe n the a pl cation of p wer an the me s rement cau es no c an e in the in icated

res lt within the precision of the me s rement in truments

me s rement s stem can b ig ored However, this is not the case in the fol owin situation :

a) when no seriou influen e af ects a me s rement res lt;

b) when no seriou influen e af ects a ju gment of res lt

NOT Inste d of th semic n u tor ele tric c ara teristic me sureme t with th set of p wer su ply a d c re t

so rc , th so rc mo itor u it (SMU) th t c mbin s v lta e/c re t so rc a d digital me sureme t fu ctio s, or

SMU system, h s b c mes th in ustry-wid sta d rd Th me sureme t with SMU is suita le for hig -a c ra y

me sureme ts, su h as in 6.5

6.1.2.4 Standard l ght source

A l g t source for the photometry with hig sta i ty, hig re rod cibi ty an with an

a pro riate photometric value s al b u ed

6.1.2.5 Me s ring instruments for photometry

One of the fol owin in truments s al b u ed:

sp ctro hotometer):

A sp ctro hotometer that me s res a sp ctrum by turnin a difraction gratin , an ta in

l g t of a sp cific wavelen th throu h a sl t seq ential y an selectively

b) A p ly rometer- yp in trument (man wavelen th sp ctro hotometer):

A sp ctro hotometer whic me s res a sp ctrum with a detector at the same time u in a

one-dimen ional photodiode ar ay from the difraction l g t out of a fixed difraction gratin

c) A fi ter- yp in trument (

V(λ) sp ctro hotometer):

A photometer whic has c aracteristic that are simi ar to sp ctral luminou ef icien y,

without u in a sp ctrum o tical s stem This photometer comprises a photo lectric tub ,

a photomultipl er or a photo lectromotive force device whose sen itivity distribution on the

l g t receivin side is flat an sta le with a fi ter for vis al sen itivity revision In u in this

fiter- yp photometer, the me s rin l g t s al b monoc romatic, an the wavelen th

ran e of o jective l g t s ould b within the wavelen th ran e of the me s rin in trument

NOT Th fiter- y e p otometer is n t suita le for th p otometry of th folowin pro u ts:

– pro u t whic h s a lg t mixin meth d usin e cite lg t emis io from th LED die a d th flu resc nt

su sta c a ple o to th LED die (p osp or b se LEDs), or

– pro u t of a ma y-wa ele gth lg t emis io meth d e uip e with difere t LEDs of a pluralty of

Trang 23

6.1.2.6 Me s ring instruments for radiometry

The me s rin in truments for radiometry are the fol owin :

a) A monoc rometer typ in trument (a wavelen th s an in typ monoc romatic l g t

radiometer):

A sp ctroradiometer that me s res a sp ctrum turnin a difraction gratin , an ta in

l g t of a sp cific wavelen th throu h a sl t seq ential y an selectively

b) A p ly rometer typ in trument (man wavelen th radiometer):

A sp ctroradiometer whic me s res a sp ctrum with a detector at the same time u in a

one-dimen ional photodiode ar ay from the difraction lg t out of a fixed difraction gratin

c) Optical p wer meter:

A radiometer con istin of a phototub , a photomultipl er or a photo lectromotive- orce

device Provides a flat an sta le resp n e sen itivity c aracteristic in a wavelen th ran e

of me s rement lg t, an is cal brated so as not to k e a weig ting of the resp n e

sen itivity for the wavelen th, without u in a sp ctrum o tical s stem In u in this

radiometer, the me s rin l g t s al b monoc romatic, an the wavelen th ran e of

o jective l g t s ould b within the wavelen th ran e of the me s rin in trument

6.1.2.7 Devices used for the emis ion spectrum c aracteristic me s rement

Devices with neces ary wavelen th b n width an resolution for the me s rement of the LED

The p int with zero electric p tential to a ply the p tential on e c electrode of the LED u der

test s al b the cathode terminal

6.1.3.3 Power s p ly

The p wer s p ly s al b the fol owin

a) Ap led voltage

The a pl ed voltage to a certain electrode is the p tential dif eren e b twe n the electrode

an the p int with zero electric p tential

b) Sup ly voltage

The s p ly voltage is the voltage s p led to a circ it in lu in the LED u der test

c) Polarity

The p larity of al electric p tential is sp cified by the p larity for the p int with zero

electric p tential

6.1.3.4 Shading

Durin the me s rement, s ita le s adin s al b given so that the l g t from the outside or

other emis ion do s not afect the me s rements

6.1.4 General precautions

The general precaution are as fol ows

Trang 24

Even a secon , external stres s al not ex e d this value to g arante normal o eration

of the LED u der test

b) Tran ient b haviour

Even in a tran ient state, the voltage an c r ent s al not ex e d the value of the

a solute maximum ratin

c) Con ideration for the he tin

In the event that the LED me s rement ne d to avoid a me s rement er or prod ced by

he t generation in the LED u der test d rin a me s rement p riod, the me s rement

s al b p rformed in a pulse con ition

When a solutely neces ary, in icate “Pulse me s rement", an sp cify the pulse state

6.2 Forward voltage (V

F) me s rement

A con tant c r ent source s al in prin iple b u ed for the me s rin circ it

If the forward c r ent ne d to b set to the rated value u in a con tant voltage source an a

c r ent l mitin resistor, desig the circ it as s own in Fig re 7

In s c a case, to avoid c an es in the forward voltage res ltin from ac umulated he t in

the test LED an cor esp n in c an es in the set c r ent, set the imp dan e for the drive

Trang 25

In the case of hig drivin p wer LED (hig p wer LED, hig - lu LED), the drivin c r ent

ratin is u ualy sp cified in a con ition u in a he t sink in te d of fre air con ition For the

me s rement, the LED s al b mou ted on an a pro riate he t sink, an b me s red u in

Kelvin contact in order to red ce me s rement er ors res ltin from contact resistan e an

wirin imp dan e An example of me s rement u in SMU is s own in Fig re 8

F) is a pl ed to the test

V

A R

S

Trang 26

c) or referen e p int temp rature (T

X)

6.3 Reverse voltage (V

R) me s rement

6.3.1 Purpose

To me s re the reverse voltage of the LED when a sp cified reverse c r ent is a pl ed

This me s rement is p rformed for the reverse c aracteristic test in the case of LED

moutin a p ral el-con ected Zener diode for electrostatic dis harge protection In me s rin

voltage at a rated c r ent, thou htles me s rement of the reverse voltage for a general LED

without an protection circ it s ould not b p rformed to avoid a stres voltage at bre kdown

voltage or a ove the a solute maximum ratin of reverse voltage

R) is a pl ed to the

Trang 27

6.3.5 Specified con itions

The sp cified con ition are as fol ows:

– reverse c r ent (I

R);

– ambient temp rature (T

a), case temp rature (T

X)

6.4 Dif erential resistance (r

f) me s rement

6.4.1 Purpose

To me s re the diferential resistan e of the LED in sp cified me s rin con ition

NOT Ge eraly th series resista c of a LED is gre ter th n th t of a g n ral re tifier dio e This

me sureme t is p rforme to d termin re uire drivin v lta e a d to d sig th drivin circ it for a p wer LED

NOT If th re io in whic th forward c ara teristic c rv of th LED c n b su sta tialy re ard d as a

straig t ln n ar th sp cifie c r e t, th me sureme t c n also b p rforme b c lc latin th resista c v lu

b se o th gra ie t of th c re t a d v lta e v lu s b twe n two p ints n ar th re io

6.4.4 Me s rement procedure

The sp cified forward DC c r ent an AC c r ent to b s p rimp sed are a pl ed to the test

LED

Afer me s rement of forward c r ent an forward voltage waveforms of the LED with a

cal brated os i os o e, the dif erential resistan e is calc lated u in their ampl tu e by the

Trang 28

f

IV

The precaution to b o served are as folows

a) The freq en y of AC c r ent to b s p rimp sed s ould b arou d 10 kHz so that it wi

not afect the me s rement

b) The forward c r ent in lu in AC c r ent s ould b as hig as p s ible within the rated

value

c) For detai s other than those provided in a) an b) a ove, se 6.1

6.4.6 Sp cified con itions

– the value of forward c r ent an the ampl tu e of AC c r ent to b s p rimp sed, or the

ampl tu e mod lation factor (

Fs/)(

X)

6.5 Reverse c r ent (I

R) me s rement

Trang 29

6.5.3 Provisions

Sin e the reverse c r ent is extremely smal within the rated a pl ed voltage, the

me s rement b comes the “min te c r ent me s rement” It is desira le to have a s ield to

el minate foreig noise, prevent le ks at ca les an the con ectin terminals, an prevent an

electrostatic dis harge If the SMU has a c r ent l miter fu ction, it is desira le to set the

c r ent l miter to prevent the test LED from b in destroyed

The reverse c r ent (I

R) is me s red when sp cified reverse voltage (V

R) is a pl ed to the

test LED

6.5.5 Precautions to be observed

Se 6.1

6.5.6 Specified con itions

– reverse voltage (V

R);

– ambient temp rature (T

X)

6.6 Me s rement of ca acitance b twe n terminals (C

t)

To me s re the ca acitan e b twe n terminals of the LED when the sp cified reverse voltage

is a pl ed (in lu in zero bias voltage)

IEC

Trang 30

6.6.2.3 Requirements

The self b lan in brid e s stem re resents a s stem in whic the imp dan e is calc lated

u in the phase information of the sig al source an comp rison of the voltage of the AC

sig al source with the value of the voltage that is con erted from the c r ent flowin alon the

test sample

6.6.2.4 Me s rement procedure

The ca acitan e b twe n the terminals (C

t) is me s red when the sp cific DC bias voltage is

X)

6.6.3 Me s rement usin AC brid e

6.6.3.1 Purpose

To me s re the ca acitan e b twe n the terminals of the LED when the sp cified reverse

voltage is a pl ed other than for a zero-bias voltage

Trang 31

6.6.3.3 Requirements

The bias circ it for the test LED s al satisfy the fol owin con ition in order to maintain the

ac urac of the me s rement an the me s rin sig al voltage s al b a sig al that is

s f iciently smal er than the bias voltage

CC

2X

21

X)

6.7 Me s rement of junction temperature and thermal resistance (R

th(j-X))

6.7.1 Purpose

To me s re the ju ction temp rature an thermal resistan e of the LED u der esta l s ed

con ition

6.7.2 Me s rement principle

Whi e sp cified total p wer dis ip tion (P) is a pled to the LED k e in the sp cified

con ition of he t radiation an ambient temp rature, the ju ction temp rature (T

j) an the

referen e p int temp rature (T

X) at referen e p int X are me s red Thermal resistan e

R

Xj

X-jth

a), the case

temp rature (T

c) or the solderin p sition temp rature (T

S)

T

j

is estimated by u in the temp rature de en en e of the forward voltage (V

F) as a

temp rature sen itive p rameter The temp rature de en en e of forward voltage is o tained

by the me s rement of forward voltage (V

F) at diferent p ints of ambient temp rature The

rise of ju ction temp rature is estimated by the c an e in forward voltage (V

F) in u ed by

Trang 32

The thermal resistan e is clas ified into “saturated thermal resistan e” an “ ran ient thermal

resistan e” as fol ows de en in on time d ration (

p) of total p wer dis ip tion (P)

a) Saturated thermal resistan e

The thermal resistan e u der the con ition in whic the total p wer dis ip tion (P) is

contin ou ly a pl ed u ti the thermal eq i brium is re c ed

b) Tran ient thermal resistan e

The thermal resistan e when p wer dis ip tion is a pl ed for a s ort p riod of time The

value of thermal resistan e de en s on time d ration (

p) of p wer

6.7.3.1 Me s rement of temperature coef icient of forward voltage (V

F)

The relation hip b twe n the forward voltage (V

F) an ju ction temp rature (T

j) is o tained as

the temp rature co f icient by the fol owin proced re

At first, the LED is held in a varia le temp rature oven an lef u ti it is con idered to b at

eq i brium as T

j

b comes eq al to the oven temp rature Then the forward voltage (V

F) is

me s red at a smal me s rin c r ent (I

M) so that the temp rature rise by the me s rement

is negl gible

Subseq ently, several p ints of the forward voltage are me s red seq ential y cor esp n in

to the varied oven temp rature as a temp rature de en ent c aracteristic of the forward

voltage

6.7.3.2 Me s rement of c ange in forward voltage (V

F) induced by power

dis ipation (P)

The c an e in forward voltage (V

F) in u ed by the p wer dis ip tion (P) given on the LED is

me s red by the circ it s own in Fig re 14 as an example

Trang 33

Only a smal me s rin c r ent (I

M) is a pl ed to the LED where the ju ction temp rature rise

is negl gible, an the forward voltage (V

The he tin c r ent is a pl ed for p wer dis ip tion d rin a sp cified “p wer dis ip tin

M)”

is me s red again with the cal brated DC os i os o e

6.7.3.3.2 Saturated thermal resistance me s rement

Close the switc b forehan

Only a smal me s ring c r ent (I

M) is a pl ed to the LED where the ju ction temp rature rise

is negl gible, an the forward voltage (V

The he tin c r ent is a pled for p wer dis ip tion for a lon time u ti the s stem re c es

the eq i brium state

Forward voltage (V

F2) ju t af er the time of the return to only the “me s rement c r ent (I

M)”

is me s red again with the cal brated DC os i os o e

Trang 34

Figure 15 – Waveform of c ange in V

F

The me s red forward voltage V

F2

ju t afer the en of p wer dis ip tion is lower than the

forward voltage V

temp rature aferward

Fig re 15

The me s rement timin of V

F2

ju t afer the en of he tin ne d to b s ort enou h in

comp rison with the thermal time con tant of the test LED However, sin e a tran ient rin in

noise is s p rimp sed onto the o served waveform d e to the c t of of the he tin c r ent

(I

H

), V

F2

sampl n is done af er a certain delay time to avoid the influen e of the rin in noise

6.7.3.4 Calc lation of thermal resistance

The thermal resistan e from the ju ction to a certain referen e p int X, R

Xj

X-jth

/

IIbVT

T

∆

≈-

≡

t I

F1

Ch n e in forward v lta e (V

F) in u e b h at a c mulatio

d e to h atin c re t (I

H) d rin p rio (

p)

Observ d wa eform

Trang 35

Two saturated region are o served in this example

The first saturated region in icates the state in whic the LED die has almost warmed up,

whi e the last region in icates the proces u ti the case (or the solderin p int has re c ed

the ste d state

The two saturated region reflect the ju ction- o-case thermal resistan e R

th(j-c) (or the

ju ction- o-solderin p int thermal resistan e R

th(j-s)) an the ju ction- o-ambient thermal

resistan e R

th(j-a)

resp ctively

Becau e the thermal resistan e from the referen e p int is determined by t

p, the value of t

p

s al b c osen in ac ordan e with the purp se

The thermal resistan e of LEDs that the rated drivin c r ent esta l s es as umin u e of the

p(j-s)) as the value of t

sen itivity of forward voltage dif eren e ∆V

p(j-s)

IEC

Trang 36

To detect the photoc r ent sig als at the photo detector, a tran imp dan e ampl fier that

en ures s ficient resp n e c aracteristic s al general y b u ed; however, this may also b

p rformed by meas rin the voltage u in a resistor whose resistan e is low enou h to

en ure resp n ivenes an l ne rity

The rise an fal times of the pulse generator an the o tical pulse me s rement s stem

s ould b s ficiently lower than the resp n e time of the test LED The resp n ivenes of a

photo detector may worsen when outside of a sp cific wavelen th region de en in on the

cry tal ne material an device stru ture The combination of wavelen th region an device

stru tures s ould b pro erly selected

The col ective len may b omit ed if it is not ne ded de en in on the o tical c aracteristic

of the test LED

The me s rement proced re is as fol ows

a) Ap ly the sp cified forward c r ent pulse to the test LED

b) The lght emited from the LED is received by the photo detector an con erted into an

Trang 37

c) Me s re this electrical sig al with an os i os o e or other s ita le me s rement

in trument that has b en s n hronized with the pulse generator Next, me s re the rise

time (

r

an fal time (

f) (an , if neces ary, the turn-on delay time (

d(o )) an turn-of

delay time (

d(of) b sed on the relation hip b twe n the input an output waveforms

s own in Fig re 18 in ac ordan e with the fol owin definition

The time that ela ses from when the ampl tu e of the input waveform re c es 10 %

u ti that of the output waveform re c es 10 %

3) Fal time (

f)

The time req ired for the ampltu e of the output waveform to decre se from 9 % to

10 %

4) Turn-of delay time (

d(of)

The time that ela ses from when the ampl tu e of the input waveform dro s to 9 %

u ti that of the output waveform dro s to 9 %

a) The rise, fal , an delay times of the forward c r ent pulse generator an the o tical pulse

me s rement s stem s al b s ficiently lower than those of the test LED

b) The lne rity of the o tical pulse me s rement s stem s al b cor ected to within the

me s rement ran e of the me s red value b fore u e

c) For detai s other than those provided in a) an b) a ove, se 6.1

a) ambient temp rature (T

c), or referen e p int temp rature (T

X);

b) input pulse sig al (pulse c r ent, pulse width, d ty ratio)

Trang 38

Fig re 18 – Waveform of respon e time me s rement

6.9 Frequenc resp nse and c t of frequenc (f

c) me s rement

r

T

fT

d(on)

IEC

Trang 39

To detect the photoc r ent sig als of the photo detector, a tran imp dan e ampl fier that

en ures s ficient resp n e c aracteristic s al general y b u ed; however, this may also b

p rformed by me s rin the voltage u in a resistor whose resistan e is low enou h to

en ure resp n ivenes an lne rity

The resp n ivenes of a photo detector may worsen when outside of a sp cific wavelen th

region de en in on the cry tal ne material an device stru ture The combination of

wavelen th region an device stru tures s ould b pro erly selected

The freq en y variation of the AC sig al source output s al be s f iciently low, either

eq al n or s rp s in IEC 6 0 1

The col ective len may b omit ed if it is not ne ded de en in on the o tical c aracteristic

of the test LED

The me s rement proced re is as fol ows

a) Ap ly the sp cified forward c r ent to the test LED an s p rimp se the smal sig al AC

in trument s c as a sp ctrum analy er

d) Obtain i

p

(f) i

p(f ) for the alternatin c r ent i

p(f ) that cor esp n s to a s ficiently low

referen e freq en y f (f ≦ f /10 ) as the freq en y resp n e

e) The c t of freq en y (f) is the freq en y at whic the freq en y resp n e decre ses by

3 dB with resp ct to the referen e freq en y

D

L

IEC

Trang 40

a) Use the freq en y c aracteristic of the smal-sig al AC source an the o tical sig al

me s rement s stem with a ran e that is s ficiently wider than that of the freq en y

c aracteristic of the LED

b) The l ne rity of the o tical sig al me s rement s stem s ould b cor ected to within the

me s rement ran e of the me s red value b fore u e

c) When photo lectric con ersion is p rformed on the o tical output from the LED by a photo

detector, b cau e the freq en y at whic the electric output from the photo detector

decre ses by 3 dB an that at whic the o tical output of the l g t source decre ses by

3 dB an are dif erent, b careful not to p rform the con ersion in or ectly

d) For detai s other than those provided in a), b), an c) a ove, se 6.1

a) ambient temp rature (T

c), or referen e p int temp rature (T

X);

b) bias forward c r ent (I

F) of the LED;

test LED at the centre of the integratin sphere an re d the output value from e c

photometer With I

VS

as the o tical output of the photometer when the luminou - lu stan ard

LED is i uminated u der esta l s ed con ition an I

VT

as the o tical output of the

photometer when the test LED is i uminated, the total flu Φ

VT(1m) of the test LED wi b as

fol ows

VSVT

II

dif er gre tly, it may b p rtic larly a pro riate to have a fiter

whose at en ation is known b twe n the photometer an the photometer win ow

6.10.3 Me s ring circ it

Tiêu đề	IEC 60747-5-6:2016 - Semiconductors – Part 5-6: Optoelectronic Devices – Light Emitting Diodes
Trường học	International Electrotechnical Commission (IEC) - Geneva
Chuyên ngành	Electrical and Electronic Standards
Thể loại	Standard
Năm xuất bản	2016
Thành phố	Geneva

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Dung lượng	3,14 MB