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I am trying to incorporate the ADA4898-2 into my simulation. The KiCad symbol shows up with only 3 pins: 2 input, 1 output, while the actual op amp has two more supply pins: +Vs and -Vs. If I try to associated the .cir file supplied by Analog Devices with the ADA4898-2 circuit symbol from the KiCad library and then try to run the simulation, I get the error:

warning, model type mismatch in line
s1 98 1030 106 113 switch
warning, model type mismatch in line
s2 1 100 106 113 switch
warning, model type mismatch in line
s3 9 101 106 113 switch
warning, model type mismatch in line
s5 81 82 83 113 switch
warning, model type mismatch in line
s4 104 313 106 113 switch
Circuit: KiCad schematic
Too few parameters for subcircuit type "ada4898" (instance: xxu1)
Doing analysis at TEMP = 27,000000 and TNOM = 27,000000
Fatal error: DCtrCurv: source / resistor +vdc not in circuit
doAnalyses: no such device
run simulation(s) aborted

How can I fix this? Why isn't the KiCAD component EXACTLY like the actual device from Analof Devices? Afterall, it was given the exact same name...

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  • \$\begingroup\$ The simulation side of things is seperate to the schematic symbols, the symbols in general where designed and added well before the simulation package was added, as such you may need to rename the pins in your model to match the symbol or vice versa. \$\endgroup\$ – Reroute Jul 8 '20 at 12:35
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    \$\begingroup\$ Some devices will have symbols with multiple components. This is common in op amps (especially dual and quad amplifiers) and logic gates, where you might have a separate symbol for each individual amplifier or gate, plus an extra symbol that holds the power pins. KiCAD labels them as "UxA", "UxB", and so on when they're placed on the schematic. I don't recall exactly how to place the other parts of a device though. \$\endgroup\$ – Hearth Jul 8 '20 at 14:01
  • \$\begingroup\$ @Hearth handling of multi unit symbols is explained in this tutorial forum.kicad.info/t/… section "Multi Unit Symbols" \$\endgroup\$ – Rene Pöschl Jul 10 '20 at 14:55
  • \$\begingroup\$ Many digital logic parts have hidden power and ground pins in the schematic symbol that the program will automatically connect to like-named power and ground nets, so we don't have to clutter the schematic with power and ground wires running everywhere. Possibly that op-amp has hidden power pins - you could edit the schematic symbol to check. \$\endgroup\$ – Peter Bennett Jul 10 '20 at 15:06
  • \$\begingroup\$ You demand a lot of accuracy from others. That is brave for someone who spells Analof Devices. \$\endgroup\$ – pipe Jul 10 '20 at 15:10
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The official library (the library that comes with a KiCad installation) focuses on the core usecase of KiCad which is PCB design. This means the symbols are made to best fit that usecase. (The pin numbers are chosen to fit the footprint meant for this symbol. Footprint pad numbers come from industry standards like JEDEC.)

Simulation is supported by special symbols placed in libraries with prefix "Simulation_". In your case you could use the OPAMP symbol from the Simulation_SPICE library.

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