SPICE: Defining Components

[Kingfish]

Greetings –

I would like to map out the IRFP4110 MOSFET to SPICE. I am using LTSpice, however the definition is not available. Instead – I borrowed another component within the library that is similar and reverse the model back to map with the spec sheet and kindly ask The Forum to check my work. In this manner I hope to map out other components as well and post them here.

IRFP4668PbF

SPICE Model

.model IRFP4668 VDMOS(Rg=2 Vto=4.85 Rd=1m Rs=1m Rb=1.2m Kp=33 lambda=0.01 Cgs=8n Cgdmin=500p Cgdmax=1n Cjo=4n Is=2n mfg=International_Rectifier Vds=200 Ron=8m Qg=161n)

VDMOS – How can I determine the device is of this type from the spec sheet? Is it by virtue of the schematic symbol?

Mapping to the Spec: SPICE Id -> Spec Id (LTSpice definition and other notes)
? = I don’t know how to map this to the Spec.

Rg = Rg (1, Gate ohmic resistance)
Vto = ? (Threshold voltage)
Rd = ? (Drain ohmic resistance)
Rs = ? (Source ohmic resistance)
Rb = ? (Body diode ohmic resistance)
Kp = ? (Transconductance parameter)
Lambda = ? (Channel-length modulation)
Cgs = ? (Gate-source capacitance)
Cgdmin = ? (Minimum non-linear G-D capacitance)
Cgdmax = ? (Maximum non-linear G-D capacitance)
Cjo = ? (Zero-bias body diode junction capacitance)
Is = Is (1, 2, Body diode saturation current)
Mfr = given: Name of Manufacturer (Note that spaces are replaced with underscores)
Vds = Vdss (Drain-source voltage rating)
Ron = Rds(on) (Nominal on resistance)
Qg = Qg (Nominal gate charge required to get to Ron)

Notes:

1. SPICE value does not match the Spec.
2. Units do not match.

I apologize for my noobness but the mapping just isn’t straight-forward. Are some of these values calculated?

Thanks, KF

 

[dnmun]

try IRFB4110

 

[Kingfish]

try IRFB4110

Oh thanks Dennis for that!
I found it in the LT Library just fine - but cannot locate where it is defined in the standard.mos file. Very odd :?

Also found this: IRFB4110 Spec that has a link to an SPI-type SPICE definition.

Although I would still like to know how to map the LTSpice ids top the Spec ids.

You know...
Give a man a fish; feed him for a day.
Teach a man how to fish; feed him for a lifetime.

Make sense?
Trying to bait the hook, KF

 

[dnmun]

it has been 37 years since i had to do SPICE modeling for my senior level EE projects. not even a memory anymore.

 

[Kingfish]

OK, I did a bit more digging. There are two solutions to the SPICE problem:

1. Easiest is to keep searching the web for a SPICE file matching the component. For International Rectifiers, I lucked out and found this page that handily carries a link to a SPICE (spi) file. With a little bit of work I was able to create a matching Symbol in LTSpice. Similarly, I found a listing of Components Library and Circuits on the LT Wiki which was very helpful and even had a test circuit for the component of interest.

2. The second choice is far more daunting for the noob. For example:
Threshold voltage.

Searching on how to resolve Drain ohmic resistance (Rd), I found this explanation to be quite useful, as was the relative diagram that helped put these parameters into perspective:

MOSFETschematic

This certainly makes sense for most of the remaining parameters.

For Kp and Lambda though, I cannot see how these are derived from the Datasheet. The examples I have found online reference the Model information direct from the manufacturer – which leads us back to going the easy route. :?

Anyways – I figured out how to get the information to create component models of interest.

Other references:
SPICE Simulation Software
SPICE Model Parameters for RIT MOSFET’s (pdf)
SPICE Model Links (includes a list of manufactures)

Satisfied for the moment. KF