modelIdealizedOpAmpLimited
Extends from Modelica.Icons.ObsoleteModel (Icon for classes that are obsolete and will be removed in later versions).
Information
Idealized operational amplifier with saturation:
- Input currents are zero.
- No-load amplification is high (but not infinite).
- Output voltage is limited between positive and negative supply.
Supply voltage is either defined by parameter Vps and Vns or by (optional) pins s_p and s_n.
In the first case the necessary power is drawn from an implicit internal supply, in the second case from the external supply.
If initialization is problematic for a model containing this as a component you can set the homotopyType parameter. Using Linear ignores the saturation initially which simplifies the initialization, and may help if the component is connected with negative feedback; but generally fails if the feedback is positive. Using LowerLimit (or UpperLimit) gives a fixed value within the saturation bounds, which works with positive feedback. However, it does not work if the intent is to initialize the input to give a specific output.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Real | V0 | 15000.0 | No-load amplification |
| Boolean | useSupply | false | Use supply pins (otherwise constant supply) |
| SI.Voltage | Vps | +15 | Positive supply voltage |
| SI.Voltage | Vns | -15 | Negative supply voltage |
| Advanced | |||
| Boolean | strict | true | = true, if strict limits with noEvent(..) |
| Initialization | |||
| Modelica.Blocks.Types.LimiterHomotopy | homotopyType | Modelica.Blocks.Types.LimiterHomotopy.NoHomotopy | Simplified model for homotopy-based initialization |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Electrical.Analog.Interfaces.PositivePin | in_p | Positive pin of the input port | |
| Modelica.Electrical.Analog.Interfaces.NegativePin | in_n | Negative pin of the input port | |
| Modelica.Electrical.Analog.Interfaces.PositivePin | out | Pin of the output port | |
| Modelica.Electrical.Analog.Interfaces.PositivePin | s_p | Optional positive supply pin | |
| Modelica.Electrical.Analog.Interfaces.NegativePin | s_n | Optional negative supply pin |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| SI.Voltage | vps | Positive supply voltage | |
| SI.Voltage | vns | Negative supply voltage | |
| SI.Voltage | v_in | in_p.v - in_n.v | Input voltage difference |
| SI.Voltage | v_out | out.v | Output voltage to ground |
| SI.Power | p_in | in_p.v*in_p.i + in_n.v*in_n.i | Input power |
| SI.Power | p_out | out.v*out.i | Output power |
| SI.Power | p_s | -(p_in + p_out) | Supply power |
| SI.Current | i_s | p_s/(vps - vns) | Supply current |