# How to obtain SPICE parameters from a LED datasheet

Status
Not open for further replies.

#### pascualhr

##### Newbie level 3 First of all I am sorry if I haven't located the thread in the correct section. :roll:

I need to model a LED diode in AWR and the datasheet doesn't provide the SPICE parameters. Could anybody explain me if it is possible to obtain these parameters?

If there is a better solution to model the LED that I am going to use in my project, please tell me, I'm all ears. Many thanks in advance!

#### FvM

##### Super Moderator
Staff member The post is basically O.K. in Analog Circuit Design forum.

A basic diode model can be made with Is, Rs, N, xti, cj0. It's relative easy to adjust the parameters to comply with a datasheet.

#### pascualhr

##### Newbie level 3 The post is basically O.K. in Analog Circuit Design forum.

A basic diode model can be made with Is, Rs, N, xti, cj0. It's relative easy to adjust the parameters to comply with a datasheet.

Thank you very much for your quickly response, FvM. I really appreciate this.

The problem is that I don't have those parameters. Here you can find attached the datasheet.

#### Attachments

• KP-2012SURCK(Ver.15A).pdf
347.8 KB · Views: 5

#### SunnySkyguy

##### Advanced Member level 5 The post is basically O.K. in Analog Circuit Design forum.

A basic diode model can be made with Is, Rs, N, xti, cj0. It's relative easy to adjust the parameters to comply with a datasheet.

It's much easier to find the parameters than guess them.

.model PT-121-B D(Is=4.352e-7 Rs=.032 N=8.37 Cjo=5n Xti=100 Iave=20A Vpk=5.3 mfg=Luminus type=LED)
.model AOT-2015 D(Is=5.961e-10 Rs=1.07 N=6.222 Cjo=.5n Xti=200 Iave=175mA Vpk=5 mfg=AOT type=LED)
.model LXHL-BW02 D(Is=4.5e-20 Rs=.85 N=2.6 Cjo=1.18n Xti=200 Iave=400mA Vpk=5 mfg=Lumileds type=LED)
.model LXK2-PW14 D(Is=3.5e-17 Rs=.725 N=3.12 Cjo=1.2n Xti=200 Iave=1.6 Vpk=5 mfg=Lumileds type=LED)
.model Luxeon1 D(Is=2.27n Rs=0.25 N=6.79 Cjo=42p Iave=350m mfg=Lumileds type=LED)
.model NSPW500BS D(Is=.27n Rs=5.65 N=6.79 Cjo=42p Xti=200 Iave=30m Vpk=5 mfg=Nichia type=LED)
.model NSCW100 D(Is=16.88n Rs=8.163 N=9.626 Cjo=42p Xti=200 Iave=30m Vpk=5 mfg=Nichia type=LED)
.model QTLP690C D(Is=1e-22 Rs=6 N=1.5 Cjo=50p Xti=100 Iave=160m Vpk=5 mfg=Fairchild type=LED)
.MODEL TLSV5100GREEN D(IS=1.7e-20 N=1.8 RS=8 Ikf=2m Eg=2.4 Cjo=50p Bv=6 Ibv=10u mfg=Vishay type=LED)
.MODEL TLSV5100RED D(IS=2.1e-19 N=1.8 RS=10 Ikf=1.1m Eg=2.3 Cjo=50p Bv=6 Ibv=10u mfg=Vishay type=LED)
.model NSSW008CT-P1 D(Is=.23f Rs=17.6 N=3.43 Cjo=42p Xti=120 Iave=35m Vpk=5 mfg=Nichia type=LED)
.model NSSWS108T D(Is=1.13e-18 Rs=14.9 N=3.02 Cjo=42p Xti=150 Iave=35m Vpk=5 mfg=Nichia type=LED)
.MODEL LedRed D (IS=93.2P RS=42M N=3.73 BV=4 IBV=10U CJO=2.97P VJ=.75 M=.333 TT=4.32U Iave=40m Vpk=4 type=LED)
.MODEL LedGreen D (IS=93.2P RS=42M N=4.61 BV=4 IBV=10U CJO=2.97P VJ=.75 M=.333 TT=4.32U Iave=40m Vpk=4 type=LED)
.MODEL LedBLUE D (IS=93.2P RS=42M N=7.47 BV=5 IBV=10U CJO=2.97P VJ=.75 M=.333 TT=4.32U Iave=40m Vpk=5 type=LED)
.model LedWHITE D(Is=0.27n Rs=5.65 N=6.79 Cjo=42p Iave=30m Vpk=5 type=LED)
.MODEL XlampMX6 D IS=4.3302E-9 N=6.4231 RS=1.0062 XTI=55 EG=2.5 Iave=1 mfg=CREE type=LED
.MODEL XlampMX3 D IS=2n N=6.4231 RS=2 XTI=55 EG=2.5 Iave=350m mfg=CREE type=LED
.model W724C0 D(Is=1.396n N=5.727 Rs=43.6m Ikf=.3128 Xti=3 Eg=3.4 Ipk=2.8 Diss=11.8 mfg=Seoul_Semi type=LED)
.model UPWLEDxx D(Is=1E-30 N=1.923 Rs=32.09 Eg=3.6 Cjo=63.87p M=.1513 Vj=2.02 Fc=.5 Isr=1.304m Nr=3.4Meg Bv=12 Ibv=369.5u Tt=432.8n Xti=5 Iave=30m Vpk=8 mfg=Microsemi type=LED)
.model UPBLED-470B D(Is=1E-30 N=1.923 Rs=32 Ikf=42.04 Eg=3.6 Cjo=63.87p M=.1513 Vj=2.02 Fc=.5 Isr=1.3m Nr=3.4Meg Bv=12 Ibv=369.5u Tt=432.8n Xti=5 Iave=30m Vpk=8 mfg=Microsemi type=LED)

The biggest problem is working with poor specs and no Spice models, and I have no use for Spice, since it does not compute junction temperature rise.
Nor does the Spice Model tell you which bin the result is in or if it is TYP, MIN or MAX. nor does it factor Shockley effect from your heatsink and device Thermal resistance, so basically just a rough answer .

I have successfully modelled without difficulty and posted many times in this forum, many examples, equally accurate and can do it in my head, it is so simple using Ohm's Law any my computation for ESR and Vth.

But that's a different question.

#### pascualhr

##### Newbie level 3 It's much easier to find the parameters than guess them.

.model PT-121-B D(Is=4.352e-7 Rs=.032 N=8.37 Cjo=5n Xti=100 Iave=20A Vpk=5.3 mfg=Luminus type=LED)
.model AOT-2015 D(Is=5.961e-10 Rs=1.07 N=6.222 Cjo=.5n Xti=200 Iave=175mA Vpk=5 mfg=AOT type=LED)
.model LXHL-BW02 D(Is=4.5e-20 Rs=.85 N=2.6 Cjo=1.18n Xti=200 Iave=400mA Vpk=5 mfg=Lumileds type=LED)
.model LXK2-PW14 D(Is=3.5e-17 Rs=.725 N=3.12 Cjo=1.2n Xti=200 Iave=1.6 Vpk=5 mfg=Lumileds type=LED)
.model Luxeon1 D(Is=2.27n Rs=0.25 N=6.79 Cjo=42p Iave=350m mfg=Lumileds type=LED)
.model NSPW500BS D(Is=.27n Rs=5.65 N=6.79 Cjo=42p Xti=200 Iave=30m Vpk=5 mfg=Nichia type=LED)
.model NSCW100 D(Is=16.88n Rs=8.163 N=9.626 Cjo=42p Xti=200 Iave=30m Vpk=5 mfg=Nichia type=LED)
.model QTLP690C D(Is=1e-22 Rs=6 N=1.5 Cjo=50p Xti=100 Iave=160m Vpk=5 mfg=Fairchild type=LED)
.MODEL TLSV5100GREEN D(IS=1.7e-20 N=1.8 RS=8 Ikf=2m Eg=2.4 Cjo=50p Bv=6 Ibv=10u mfg=Vishay type=LED)
.MODEL TLSV5100RED D(IS=2.1e-19 N=1.8 RS=10 Ikf=1.1m Eg=2.3 Cjo=50p Bv=6 Ibv=10u mfg=Vishay type=LED)
.model NSSW008CT-P1 D(Is=.23f Rs=17.6 N=3.43 Cjo=42p Xti=120 Iave=35m Vpk=5 mfg=Nichia type=LED)
.model NSSWS108T D(Is=1.13e-18 Rs=14.9 N=3.02 Cjo=42p Xti=150 Iave=35m Vpk=5 mfg=Nichia type=LED)
.MODEL LedRed D (IS=93.2P RS=42M N=3.73 BV=4 IBV=10U CJO=2.97P VJ=.75 M=.333 TT=4.32U Iave=40m Vpk=4 type=LED)
.MODEL LedGreen D (IS=93.2P RS=42M N=4.61 BV=4 IBV=10U CJO=2.97P VJ=.75 M=.333 TT=4.32U Iave=40m Vpk=4 type=LED)
.MODEL LedBLUE D (IS=93.2P RS=42M N=7.47 BV=5 IBV=10U CJO=2.97P VJ=.75 M=.333 TT=4.32U Iave=40m Vpk=5 type=LED)
.model LedWHITE D(Is=0.27n Rs=5.65 N=6.79 Cjo=42p Iave=30m Vpk=5 type=LED)
.MODEL XlampMX6 D IS=4.3302E-9 N=6.4231 RS=1.0062 XTI=55 EG=2.5 Iave=1 mfg=CREE type=LED
.MODEL XlampMX3 D IS=2n N=6.4231 RS=2 XTI=55 EG=2.5 Iave=350m mfg=CREE type=LED
.model W724C0 D(Is=1.396n N=5.727 Rs=43.6m Ikf=.3128 Xti=3 Eg=3.4 Ipk=2.8 Diss=11.8 mfg=Seoul_Semi type=LED)
.model UPWLEDxx D(Is=1E-30 N=1.923 Rs=32.09 Eg=3.6 Cjo=63.87p M=.1513 Vj=2.02 Fc=.5 Isr=1.304m Nr=3.4Meg Bv=12 Ibv=369.5u Tt=432.8n Xti=5 Iave=30m Vpk=8 mfg=Microsemi type=LED)
.model UPBLED-470B D(Is=1E-30 N=1.923 Rs=32 Ikf=42.04 Eg=3.6 Cjo=63.87p M=.1513 Vj=2.02 Fc=.5 Isr=1.3m Nr=3.4Meg Bv=12 Ibv=369.5u Tt=432.8n Xti=5 Iave=30m Vpk=8 mfg=Microsemi type=LED)

The biggest problem is working with poor specs and no Spice models, and I have no use for Spice, since it does not compute junction temperature rise.
Nor does the Spice Model tell you which bin the result is in or if it is TYP, MIN or MAX. nor does it factor Shockley effect from your heatsink and device Thermal resistance, so basically just a rough answer .

I have successfully modelled without difficulty and posted many times in this forum, many examples, equally accurate and can do it in my head, it is so simple using Ohm's Law any my computation for ESR and Vth.

But that's a different question.

So sorry, but I haven't understood what you said.
Could you help me please?

I have tried to extract some points from the IV curve that it is in the datasheet, and then add them into a .ivd file and importing it into AWR. But I think that this is not the correct way to do that.

How could I extract the Is, Rs, N, etc in an easy way?

Thank you so much in advance!

Status
Not open for further replies.