SPICE controller allows you to easily simulate analog circuits within eCADSTAR Schematic Editor. It uses an embedded version of the free high-performance simulation software, and waveform viewer LTspice®, from Analog Devices. LTspice® provides enhancements and models for the simulation of analog circuits. You can download it from the Analog Devices website. It allows you to view graphical waveforms, conduct speculative analysis, change discrete values, and run parameter sweeps.
When a simulation is executed, an additional folder named "SimA" is created within the relevant design folder. The following simulation files, which are created by the simulator, are added and are required to open the simulations.
- Element name conversion list file ([Circuit name].ade): links component IDs and element names to each other.
- Analog Unit net list ([Circuit name].adn): a netlist for the SPICE Controller Manager. You can create it from the schematic data using the Netlist Out dialog.
- Analog Unit Project File ([Circuit name].adp): the project file that the SPICE Controller Manager creates for each simulation. Data such as power, input signals, analysis conditions, and simulator types are saved here.
- Analysis result list ([Circuit name].log): the output file for LTspice, which provides the analysis result in text format. Error and warning messages, and the analysis duration are also listed.
- SPICE net list ([Circuit name].net): the input file for LTspice. This is outputted by the SPICE Controller Manager. This file mainly comprises analysis and element statements.
- Analysis Results Waveform file ([Circuit name].raw): an output file for LTspice. This provides the resultant waveform data for the dedicated waveform display tool.
- Include files (.inc): these are text files that may contain analysis statements, circuit nets, and device models for LTspice. If you specify include files in SPICE Controller Manager, then they are loaded when you perform the analysis.
To support multi-gated, analog semiconductor devices in the LTspice simulator, you must configure the relevant part in eCADSTAR Library Editor. See: Using Multi-gated, Analog Semiconductor Devices with the LTspice Simulator, which also describes the following.
- How to use a multi-gated analog semiconductor device in a design.
- The priority order used by eCADSTAR to map the pins from the schematic symbols to the pin sequence order of the SPICE model.
- If you save the library as a different version by clicking Save As in eCADSTAR Library Editor, then note the following.
- Older version: all SPICE properties and SPICE pin assignments are deleted.
- Newer version: all SPICE properties are assigned defaults, with no values set.
- If you add a new part to a PCB design, and then execute Back Annotation, the SPICE properties and SPICE pin assignments are displayed in schematic editor using the values stored for the part in eCADSTAR Library Editor. If you execute Forward Annotation, these properties and pin assignments are not added to eCADSTAR PCB Editor.
- LTspice values that you specify must not contain spaces.
- For further information on configuring and using LTspice, see the following user guide.
Simulation Properties for Components and Pins
The following LTspice simulation properties can be set in the Properties panel in eCADSTAR Schematic Editor. They can be specified for a part in the Part Editor Panel: SPICE tab, SPICE Part Attributes table, or in the Library Editor Panel: Parts Tab. If you specify SPICE attributes in the Library Editor Panel: Parts Tab or the Part Editor Panel: SPICE Tab, then the specified values are shown in the Properties panel in eCADSTAR Schematic Editor when the part is added to the canvas. See Banned Characters.pdf for the characters that are prohibited for these values.
The SPICE attributes that you specify in the Properties panel in eCADSTAR Schematic Editor are not added to the library. When simulating with parts, it is recommended to add them to the library instead. However, this is not necessary when simulating only with symbols.
| Item | Description | ||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Element Name or Element Header | Specifying an element value
in the Properties
panel, Element Name or Element
Header rows allows
you to override the reference designator within the simulator.
Because SPICE identifies the device type based on the lead Character
of its reference or the element name, this can be beneficial.The
relationship between device types and head characters is shown
below. For example, "IC" would be identified as a "Current
Source." Changing the element header to "X1" or
adding "X" in the element header would mean the component
is the recognized as a subcircuit.
|
||||||||||||||||||||||||
| SPICE Simulation Value | This is a basic part property in eCADSTAR which defines the electrical characteristics of passive elements. It provides the resistance value (Ω), capacitance value (F), or inductance value (H) of resistors, capacitors, and inductors, respectively. If the simulation value is different to this, then the simulation value is used in the analysis. | ||||||||||||||||||||||||
| SPICE Model Name | This is a dedicated LTspice property which defines the electrical characteristics of active elements. It provides the device model name that is used for analyzing active elements such as transistors or various types of IC. To be used in the analog unit, you must add the device model as an include file in the Schematic Editor: Application Settings dialog. | ||||||||||||||||||||||||
| SPICE Substrate Connection Node | For BJT, JFET, or MOSFET devices, this specifies the net to connect to a substrate pin. Set the net name to specify a substrate (bulk) connection target. You cannot set it for a device model in subcircuit (.SUBCKT) format, even if the device type is BJT, JFET, or MOSFET. | ||||||||||||||||||||||||
| SPICE Parameter 1-10 | These are SPICE Controller properties which define supplementary electrical characteristics for LTspice. They are general purpose values that can represent parameters in the model file, or other spice parameters. All available parameters for SPICE components are listed in the LTspice Help. The items that you can set vary depending on the type of the element. For example, for passive elements you can set temperature coefficients (up to secondary coefficients). For active elements, you can set physical information on semiconductors. Set the characteristics by typing "[parameter]=[value]" in the Value column. Many of these properties can be omitted. |
