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How to handle multiple unit ICs (e.g. quad op-amps) in PSPICE for TI

Roger Brooks
Prodigy 50 points
Other Parts Discussed in Thread: TL074, TL071, TLV9002, TLV9004, TLV9001, TL074H, TL103WB, INA351, INA351A

I am using PSPICE for TI to simulate a preamplifier based on TL074. When I add the op-amps to the schematic, each unit appears as a separate IC.  How can I make PSPICE realize that all 4 units belong to the same package, and need only one pair of connections to DC power?

P.S. I chose "I don't have a part number" above because this is not a part-specific question and, if I supply the part number, I can no longer select the appropriate forum.

  • 0
    TI__Mastermind 20460 points

    Hi Roger,

    Let me see if I understand what you're trying to do. You've placed the TL074 in your circuit, but it's showing as a single op-amp, not as a quad. 

    I see the same thing. Other than the annoyance of having to route V+ and V- (or using a labled wire which would be a fine short cut, do you have concerns about the model itself?

    The only way to get this as a single part would be for the product group to release this as a 4 op-amp solution in a 14 pin package (in the tool).

    We can pull them in if that's what you really need. I do not know why the chose to release a quad as a single. Probably just re-used the TL071 and called it a day.

    I'm able to do the named wire thing, but am currently having issues showing the netlist name on the wire. Once I've resolved that, I'll include an image of what I'm doing for you to see.

    David

  • 0 in reply to David Larkin
    TI__Mastermind 20460 points

    Hi Roger,

    You can place one instance of TL074, and put wires on V+ and V-, then use Place -> Net Alias to name these connections. Then copy paste to reproduce.

    There is a capability to edit properties, but I ran into problems with that. It will allow you to rename the wire, but displaying that change didn't always work, but Adding a Net Alias did always work.

    David

  • 0 in reply to David Larkin
    TI__Mastermind 22332 points

    Hey Roger, 

    Thanks for your question and welcome to e2e! :) 

    For op amps, since there is no differences in the IC behavior between the channel counts, we will often have one 1 IC in the simulation that may be placed multiple times regardless of channel count. This is more of general theme since op amps have been around for a very long time and the model developers have changed throughout the years. These days for our modern op amps, there is one op amp (usually the channel count that is released first) that represents the whole family - TLV9002 for the TLV9001, TLV9002, and TLV9004. 

    In this case, the quad is represented as 1 IC and may be placed four times. 

    In my schematics, I often use the "VCC_BAR" that can be found under the place menu under power, or keyboard shortcut "F." 

    This power net can be renamed and used frequently throughout the schematic pages, see below. 

    Since PSpice for TI is used as a simulation engine, this is often times enough for customers; however, I can see the use case for what you are describing if this was being laid out and fabricated. 

    Since it appears you are in the introductory stages of your design, I recommend upgrading from TL074 to TL074H. 

    All the best,
    Carolina 

  • 0 in reply to Caro Walter
    Prodigy 50 points

    Dear Carolina,

    You guessed it! I need a quad because I will pass the design on to a colleague for PCB layout. The type of the op-amp is not critical.  I didn't find the TL074H as a quad in my library: only TL07X as a single. Is there another popular low-noise, jfet op-amp in the PSPICE for TI library which is packaged as a quad?

    Thanks for your help!

  • 0 in reply to Roger Brooks
    TI__Mastermind 33573 points

    Hey Roger,

    You can probably create a custom symbol in PSpice for your schematic entry for layout, then connect the nodes together for simulation. Unfortunately, the integrated library just has the spice models there, but this does mean that if you want to attach a footprint to the custom symbol, you can grab that from the product page!

    All of the devices that we have SPICE models for are all created as single channel op amps. The only devices that have multiple devices in them in them are the ones that don't come in other channel flavors (TL103WB and INA351/INA351A).

    Best,
    Jerry

  • 0 in reply to Gerasimos Madalvanos
    Prodigy 50 points

    Hi Jerry,

    It is a pretty simple circuit, and my friend wants to use KiCad for layout, so it will be easier to just recapture the schematic in KiCad.

    Thanks for your help.

    Roger