Vendor-supplied SPICE models for fixed linear voltage regulators are rare so most models available on the Internet have been created by individuals trying to fill the void. I came across the following post on a KiCad forum which contains models for the LM7809 and LM7909 regulators. These were created from adjustable LM317 and LM337 models by adding parameters to produce a +/- 9-volt output.
SPICE Models LM78xx & LM79xx Series
Based on this work, I created generic models from which any fixed regulator model can be created by passing two parameters. While these particular LM317 and LM337 models are not very accurate compared to the Texas Instruments models, the supplied parameters can be tweaked to create the desired output voltage.
I spent an afternoon creating models for the most popular fixed regulators and have compiled them into a library. My library also includes the TI models for the LM317 and LM337 adjustable regulators, which I've found to be very accurate.
In the spirit of giving back I've attached my library here, along with a "universal" symbol (reg.asy) that can be used with all models. This library comes with the usual caveats: no warranties implied, use at your own risk, etc.
Edit: Library updated May 16, 2025
SPICE Models LM78xx & LM79xx Series
Based on this work, I created generic models from which any fixed regulator model can be created by passing two parameters. While these particular LM317 and LM337 models are not very accurate compared to the Texas Instruments models, the supplied parameters can be tweaked to create the desired output voltage.
I spent an afternoon creating models for the most popular fixed regulators and have compiled them into a library. My library also includes the TI models for the LM317 and LM337 adjustable regulators, which I've found to be very accurate.
In the spirit of giving back I've attached my library here, along with a "universal" symbol (reg.asy) that can be used with all models. This library comes with the usual caveats: no warranties implied, use at your own risk, etc.
Edit: Library updated May 16, 2025
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These models are not particularly sophisticated nor were they intended to be (see the link in the original post). That link's author needed a model for fixed positive and negative 9-volt regulators because there are no manufacturer-supplied models available, and decided to create his own. I merely extended his work to include other popular fixed voltage regulators, and I posted that library because I thought some people might find those models useful. That was probably a mistake in hindsight.
I'm sorry that these simple models are not useful to you. If you find or create something better then maybe you can post them here.
I'm sorry that these simple models are not useful to you. If you find or create something better then maybe you can post them here.
PSRR is what we use regs for.
FWIW, the Texas Instruments models for the TL431 shunt regulator were also useless for simulation.
FWIW, the Texas Instruments models for the TL431 shunt regulator were also useless for simulation.
There are reasons to model a circuit using a voltage regulator other than examining PSRR. But I'm not going to argue with you. You can either use these models or not; it's all the same to me.
