5. Parameters¶
Parameters can be set using the commands in Material Commands. There are two complementary formalisms for doing this.
5.1. Parameters¶
Parameters are set globally, on devices, or on regions of a device. The models on each device region are automatically updated whenever parameters change.
devsim.set_parameter(device="device", region="region",
name="ThermalVoltage", value=0.0259)
They may also be used to control program behavior, as listed in Table 5.1:
Parameter |
Description |
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5.2. Material database entries¶
Alternatively, parameters may be set based on material types. A database file is used for getting values on the regions of the device.
devsim.create_db(filename="foodb")
devsim.add_db_entry(material="global", parameter="q", value=1.60217646e-19,
unit="coul", description="Electron Charge")
devsim.add_db_entry(material="Si", parameter="one",
value=1, unit="", description="")
devsim.close_db
When a database entry is not available for a specific material, the parameter will be looked up on the global
material entry.
5.3. Discussion¶
Both parameters and material database entries may be used in model expressions. Parameters have precedence in this situation. If a parameter is not found, then DEVSIM
will also look for a circuit node by the name used in the model expression.