NXP provides the following model types on www.nxp.com.
The models can be accessed by clicking “get support “ → “models” or from data sheet links.

Single models

For single devices and devices using multiple dies of the same type, a single parameter set is provided, i.e. a single model for one die only (one diode or one transistor). If a package contains two or more devices of the same type (example: BCM847BS), the provided model has to be inserted twice into the schematic.

Subcircuit models

Subcircuit models contain a main and at least one sub model. This model type is used

To model devices called “complex discretes“, i.e. more than one device is integrated into one package and the devices are connected internally. Example: PSSI2021SAY

To improve modeling accuracy of some types of bipolar transistors, such as PNP and some kinds of high voltage transistors. Please note that these elements reflect no physical devices! In this case, a related remark is added to the model header.

Examples:

• Diode to improve accuracy of reverse operation mode

Fig. 1: PBSS306PX, hFE reverse vs. IE using subcircuit with additional diode	Fig. 2: PBSS306PX, hFE reverse vs. IE without diode

• Transistor to improve accuracy in quasi saturation area

Fig. 3: Output characteristic of PBSS4021PT using subcircuit with additional transistor	Fig. 4: Output characteristic of PBSS4021PT without transistor

In case of problems using these models, you can request a simple model without additional devices. Please note that this model will run with most kinds of simulators, but provides less accuracy. To get a simple model, please contact our customer service.

Multiple models: Used if several devices are placed in one package, e.g. loadswitches or MOSFET-driver. If the use of single models is preferred for simplification of the schematic, you will find a description in the model header that suggests which alternative single devices can be used from the NXP portfolio