Semiconductor Switch Selector
Libraries:
Simscape /
Electrical /
Semiconductors & Converters
Description
The Semiconductor Switch Selector block models a controlled switch that represents a metal-oxide-semiconductor field-effect transistor (MOSFET), insulated-gate bipolar transistor (IGBT), thyristor, or gate turn-off thyristor (GTO).
Simscape™ Electrical™ includes blocks that can model the same type of semiconductor device but at different levels of fidelity. For example, the MOSFET (Ideal, Switching) and N-Channel MOSFET blocks both model a MOSFET. To develop your model with the right level of complexity, you need a different fidelity level depending on the stage you are at in the design process. The Semiconductor Switch Selector block combines these different library blocks under a single top-level block mask. Use the Semiconductor Switch Selector block to change the fidelity level without replacing a block or reentering parameter values that you have already specified.
To select and parameterize the underlying library block:
Specify the type of semiconductor device using the Switching device parameter.
Specify the underlying library block using the Library block parameter.
Choose which ports you want to enable in the underlying library block using the Modeling option, Gate-control port, and Number of terminals parameters. The Modeling option parameter determines whether you expose the thermal port, H, and defines the mathematical model that the underlying library block uses. The visibility of these parameters depends on the Switching device and Library block parameters.
Click the Edit parameters button to open the block dialog box for the underlying library block and specify the block parameters.
To switch to a different underlying library block, repeat steps 2 and 4. Parameter values that are common to both blocks carry over to your new selection. The Semiconductor Switch Selector block also stores parameter values that are specific to the underlying library block, so you can easily return to a previous choice.
If you no longer want to switch between fidelities, click the Remove Semiconductor Switch Selector block mask button. This button removes the Semiconductor Switch Selector block and replaces it with the underlying block. This action is irreversible.
This table shows the underlying library blocks that the Semiconductor Switch Selector block supports for each value of the Switching device parameter. Typically, you use simpler blocks for system-level design and more complex blocks for detailed component design. For more information about choosing the right level of fidelity for your application, see Choose Blocks to Model Semiconductor Devices. For more information about the underlying library block, see the relevant block reference page from this table.
Switching Device | Library Block | |
|---|---|---|
| Low or Medium Fidelity | High Fidelity | |
| MOSFET | ||
| IGBT | ||
| Thyristor | ||
| GTO | Not supported | |
If you change the Library block parameter, the Semiconductor Switch Selector block icon updates to the underlying library block icon.
The Gate-control port, Modeling option, and Number of terminals parameters are common to the Semiconductor Switch Selector block and the underlying library block. However, you must set the values of these parameters in the Semiconductor Switch Selector block mask. If you click the Edit parameters button, the underlying library block does not enable these parameters. You can only enable these parameters in the underlying library block by removing the Semiconductor Switch Selector block mask.
If you change the Library block parameter, the values of all parameters that are common to both blocks, including initial targets and nominal values, carry over to the new block. Values of equivalent parameters that have different names in different blocks also carry over. This table shows the equivalent parameters for MOSFETs.
| Equivalent Parameter | Library Block | |||
|---|---|---|---|---|
Ideal Semiconductor Switch | MOSFET (Ideal, Switching) | N-Channel IGBT | P-Channel MOSFET | |
| Threshold voltage | Threshold voltage, Vth | Gate-source threshold voltage, Vth | ||
| On-state resistance | On-state resistance | Drain-source on resistance, R_DS(on) | ||
This table shows the equivalent parameters for IGBTs.
| Equivalent Parameter | Library Block | ||
|---|---|---|---|
Ideal Semiconductor Switch | IGBT (Ideal, Switching) | N-Channel IGBT Block | |
| Threshold voltage | Threshold voltage, Vth | Gate-emitter threshold voltage, Vge(th) | |
If you change the Switching device parameter, the parameter values do not carry over. So you can also use the Semiconductor Switch Selector block to compare an optimized MOSFET to an optimized IGBT, thyristor, or GTO.
Assumptions and Limitations
The Semiconductor Switch Selector block supports only a single thermal port, H. If you set the Library block parameter to
MOSFET (Ideal, Switching)orIGBT (Ideal, Switching), when you click the Edit parameters button, the Separate thermal port for integral diode parameter in the underlying block dialog is not enabled. If you want to model a MOSFET or IGBT with separate thermal ports for the switching device and the body diode, you must remove the Semiconductor Switch Selector block mask.
Ports
Input
Conserving
Parameters
Extended Capabilities
Version History
Introduced in R2025a
