MATLAB How to simulate Op-Amp in MATLAB

  • Thread starter Thread starter jean28
  • Start date Start date
  • Tags Tags
    Matlab Op-amp
AI Thread Summary
To simulate an operational amplifier in Simulink, a configuration using two adders and a gain block is recommended, with a high gain setting and a saturation block to limit output. Issues arise when trying to connect resistors and capacitors to the sum block due to incompatible signal types; the sum block requires pure numerical signals while resistors and capacitors use voltage signals. To resolve this, a Voltage Measurement Block and a Variable Voltage Source can be used to convert signal types appropriately. Additionally, a controlled voltage source is necessary to convert the output from the saturation block back to a voltage signal for measurement. Users are encouraged to explore block configuration panels for further understanding and troubleshooting.
jean28
Messages
83
Reaction score
0
Good day. Could anyone tell me how to simulate an equivalent Operational Amplifier in Simulink? I read somewhere that I had to do it with 2 adders and a gain block, but I don't know how. Thanks.
 
Physics news on Phys.org
---(-ve Input)----
......| (- +)SUM | ----|-Gain-> --- |Saturation Block| ---> (output)
---(+ve Input)---

Set gain very high, like 10,000. Saturation Block is used to limit the output to within certain range; for real hardware op-amps the output would saturate at power supply voltage levels.
 
I_am_learning said:
---(-ve Input)----
......| (- +)SUM | ----|-Gain-> --- |Saturation Block| ---> (output)
---(+ve Input)---

Set gain very high, like 10,000. Saturation Block is used to limit the output to within certain range; for real hardware op-amps the output would saturate at power supply voltage levels.
Ok thanks for that. Now, for some reason the resistors and capacitors don't want to connect to the Sum block. I tried the SimpowerSystems and Simscape blocks and they don't connect. Do you know why?
 
Blocks are very restrictive of what type of signals are input and what types are output.
Resisters and capacitors take 'voltage' signals as input but the 'sum' block needs pure signal (number) as input. 'Voltage Measurement Block' and 'Variable Voltage source' can convert signal of one form to other.
In short, the blocks don't connect because the signal types don't match.
 
I_am_learning said:
Blocks are very restrictive of what type of signals are input and what types are output.
Resisters and capacitors take 'voltage' signals as input but the 'sum' block needs pure signal (number) as input. 'Voltage Measurement Block' and 'Variable Voltage source' can convert signal of one form to other.
In short, the blocks don't connect because the signal types don't match.

That is great information. Is there any specific source or book that you can recommend me to learn all of these things?

I'll try to set up the whole model later on and tell you if I need any help.

P.S. Does the saturation block require another converter?
 
I_am_learning said:
Blocks are very restrictive of what type of signals are input and what types are output.
Resisters and capacitors take 'voltage' signals as input but the 'sum' block needs pure signal (number) as input. 'Voltage Measurement Block' and 'Variable Voltage source' can convert signal of one form to other.
In short, the blocks don't connect because the signal types don't match.

What converter do I need to put to the saturation block to be able to measure the output voltage?
 
The voltage measurement block measures 'voltage difference between two points' only. So, you need to connect both of its two input.

The saturation block takes in pure number and gives out pure number. To convert it to voltage signal use a 'controlled voltage source' block.
http://www.mathworks.com/help/physmod/powersys/ref/controlledvoltagesource.html

You can learn a great deal about various blocks by opening their configuration panel (double click) and choosing help.
 
Last edited:
I_am_learning said:
The voltage measurement block measures 'voltage difference between two points' only. So, you need to connect both of its two input.

The saturation block takes in pure number and gives out pure number. To convert it to voltage signal use a 'controlled voltage source' block.
http://www.mathworks.com/help/physmod/powersys/ref/controlledvoltagesource.html

You can learn a great deal about various blocks by opening their configuration panel (double click) and choosing help.

Ok, so I connected the voltage measurement blocks and then added the controlled voltage source block and I still get some weird error. What's wrong now? Did I connect the voltage measurement blocks wrong?

http://i1226.photobucket.com/albums/ee410/jean28x/modelo2attempt.jpg
 

Similar threads

Replies
1
Views
3K
Replies
5
Views
4K
Replies
5
Views
3K
Replies
7
Views
2K
Back
Top