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I am new to PCB designing and I am new to Altium. I want to make a schematic, PCB design and simulate a RF circuit involving a GPS receiver front end IC MAX2769. Altium library does not have this IC. I can create the component in library and also its layout for PCB. But for Signal Integrity simulation purposes I need to define what's inside of this IC package. How do I do that? Maxim does not provide a simulation model for this IC. Do I need to define all the individual components inside the IC package or is there any other way?

I am in real need of support right now. Thank you very much. IC internal circuit is as below.

IC internal circuit

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2 Answers 2

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You will need to get the info from Maxim or use another IC if you really want to go that way. Yet I do not see how you will benefit from this. The only use-case for Altium's signal integrity part (which I have used in the past) is for transmission lines to determine proper signal termination. If you want to simulate the RF part, I guess you're probably better off with a different simulation tool.

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  • \$\begingroup\$ Using another IC wouldn't be possible in my case as I have already did my research and found that this chip fulfills all my requirements of Gain, IF Frequency etc. I guess I'll have to work with testing of transmission lines only within Altium, unless I get another tool for RF analysis. Is there any other tool you recommend for this purpose? \$\endgroup\$
    – Umair47
    May 16, 2015 at 7:48
  • \$\begingroup\$ If you're going to simulate the RF part and beyond, maybe something like CST Studio would be appropriate (yet, a little pricey and a hell of work). But you would also be able to take casing and other components into consideration). To be honest, the only part I think Altium is capable of simulating is the 3-wire interface (but this is .. well .. I don't find it useful). \$\endgroup\$
    – Tom L.
    May 16, 2015 at 9:14
  • \$\begingroup\$ I have one more question though. Will I be able to make the whole internal circuit of this chip in the CST studio? I mean this is just the block diagram. Each component would need to be disintegrated into its own circuitry for example, say, an LNA would be composed of other active and passive components. Do you think this level of complexity could be achieved in CST studio? \$\endgroup\$
    – Umair47
    May 16, 2015 at 11:46
  • \$\begingroup\$ Since you have no exact definition of the internal parts - probably (most likely) no. But you would be able to study how the RF signal "travels" from the outside world to the antenna. To be honest: I think your only choice is to either get the model data (although I haven't seen one myself in the past) or to go the trial-and-error way we all probably have one or the other time. \$\endgroup\$
    – Tom L.
    May 16, 2015 at 13:13
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The chip you refer to is a highly-integrated system. According to the datasheet, "incorporated on the chip is the complete receiver chain, including a dual-input LNA and mixer, followed by the image-rejected filter, PGA, VCO, fractional-N frequency synthesizer, crystal oscillator, and a multibit ADC."

You are not likely to be able to get a SPICE model for such a complex chip. And if you did, it would likely be so complex that simulation requires substantial computing resources.

Better would be to use the datasheet to make a behavioral model of the chip at whatever level of detail you need. A tool like Matlab/Octave/Scilab/Numpy is better suited to modeling a chip like this than a circuit simulator.

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  • \$\begingroup\$ Thank you for your input. My intention was to perform the analysis of the chip within the circuit that I am going to implement on the PCB. That way I could have an idea how my circuit is going to operate in reality, as this is going to be my first RF design. Realizing that it would not likely be possible within a single tool, I am thinking of performing transmission lines analysis within Altium and chip analysis in another software. \$\endgroup\$
    – Umair47
    May 16, 2015 at 8:36

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