Original question:
Hello.
I am simulating a digital input model with TINA Tool, with de IC ISO1211, I can't found the ISO1211 model, there is a ISO121x Model, but the pins are very diferent from the datasheet. I'm sorry, I am new on this, I ever worked in LTSpice. Also, I want to simulate in the same circuit the TVS 3330, Where can I get the TVS 3330 model in TINA Tool? Thanks.
I am working with this. I have this schematic for simulate
But, I have a problem, the Vout is not working correctly:
I read in another post, that de FND has a problem, but I don't know if is it or I have a problem with the schematic. Please help me. Thanks.
Hi Vladimir,
Thank you for your patience. I went ahead and ran the simulation for a circuit configuration that matches the one that you showed in your initial post. To obtain a better understanding for why the simulation was not behaving as expected, I added an additional voltage measurement node at C4 (labeled as VC4 in the schematic below).
Here are the results of the above simulation:
As you can see by the simulation results above, the C4 capacitor is not able to completely charge and discharge at the same rate that VIN is switching. This is because the capacitance value of C4 is too large for the given bandwidth of VIN. To correct this, the capacitance value of C4 needs to be decreased. To observe behavior that is closer to what is expected for this device, I recommend decreasing C4 so that it has a capacitance value equal to or less than 1 nF.
As shown by the screenshots above, the device behaves as expected whenever a 1 nF capacitor is used for C4. For any applications where the input voltage signal has a bandwidth similar to VIN in this simulation, I recommend that you keep the capacitance value of C4 equal to or less than 1 nF.
Regards,
Kenneth
