modelCauerLowPassSC

Cauer low-pass filter with operational amplifiers and switched capacitors

Extends from Modelica.Icons.Example (Icon for runnable examples).

Information

The example CauerLowPassSC is a low-pass-filter of the fifth order. It is realized using an switched-capacitor network with operational amplifiers. The voltage source V is the input voltage (step), and the OP5.out.v is the filter output voltage. The pulse response is calculated.

This model is identical to the CauerLowPassAnalog example, but inverting. To get the same response as that of the CauerLowPassAnalog example, a negative voltage step is used as input.

This model is identical to the CauerLowPassOPV example. But the resistors are realized by switched capacitors (see SwitchedCapacitor). There are two different types of instances, one with a value of R=1 and one with a value of R=-1.

The simulation end time should be 60. Please plot both V.v (which is the inverted input voltage) and OP5.out.v (output voltage). Compare this result with the CauerLowPassAnalog result.

Due to the recharging of the capacitances after switching the performance of simulation is not as good as in the CauerLowPassOPV example.

Parameters

TypeNameDefaultDescription
SI.Capacitancel11.304Filter coefficient i1
SI.Capacitancel20.8586Filter coefficient i2
SI.Capacitancec11.072Filter coefficient c1
SI.Capacitancec21/(1.704992^2*l1)Filter coefficient c2
SI.Capacitancec31.682Filter coefficient c3
SI.Capacitancec41/(1.179945^2*l2)Filter coefficient c4
SI.Capacitancec50.7262Filter coefficient c5

Components

TypeNameDefaultDescription
Modelica.Electrical.Analog.Basic.CapacitorC1
Modelica.Electrical.Analog.Basic.CapacitorC2
Modelica.Electrical.Analog.Basic.CapacitorC3
Modelica.Electrical.Analog.Basic.CapacitorC4
Modelica.Electrical.Analog.Basic.CapacitorC5
Modelica.Electrical.Analog.Ideal.IdealOpAmp3PinOp1
Modelica.Electrical.Analog.Basic.GroundG
Modelica.Electrical.Analog.Ideal.IdealOpAmp3PinOp2
Modelica.Electrical.Analog.Ideal.IdealOpAmp3PinOp3
Modelica.Electrical.Analog.Basic.GroundG1
Modelica.Electrical.Analog.Basic.CapacitorC6
Modelica.Electrical.Analog.Ideal.IdealOpAmp3PinOp4
Modelica.Electrical.Analog.Ideal.IdealOpAmp3PinOp5
Modelica.Electrical.Analog.Basic.CapacitorC7
Modelica.Electrical.Analog.Basic.CapacitorC8
Modelica.Electrical.Analog.Basic.CapacitorC9
Modelica.Electrical.Analog.Basic.GroundG2
Modelica.Electrical.Analog.Basic.GroundG3
Modelica.Electrical.Analog.Basic.GroundG4
Modelica.Electrical.Analog.Sources.StepVoltageV
Modelica.Electrical.Analog.Basic.GroundGround1
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR4
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR5
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR8
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR9
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR1
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR2
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR3
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorRp1
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR7
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR10
Modelica.Electrical.Analog.Examples.Utilities.SwitchedCapacitorR11

Revisions

  • January 13, 2006 by Christoph Clauss
    included into Modelica Standard Library
  • September 15, 2005 by Peter Trappe designed and by Teresa Schlegel
    initially modelled.