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ISO7310C: ISO7310C

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Replies: 4

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Part Number: ISO7310C

Hello,

I have successfully modeled other components in TINA but the model of ISO7310C has an IBS file extension. I couldn't read it on my PC so I used an online reader. The result was copied and pasted into Note pad as a Txt file. It is a huge file. But when I try to use it in the 'New Macro Wizard' it just states - "Error Loading Library: File is empty!" But the file is anything but empty!

I have attached the txt file for your perusal.

What I have noticed is that this file is initially IBS - which I have never come acrossISO7310C.txtbefore!

Anyway thanks for your help.

Best regards,

Peter J Partridge

  • Hi Peter,

    Thank you for posting to E2E!

    IBIS models are used to model digital isolators since most simulation tools cannot model isolation performance on different GND potentials.

    IBIS models are accurate for I/O simulation, and although IBIS models can be imported as macros in the full version of TINA, IBIS models cannot be imported into TINA-TI. The .txt file attached still looks like an accurate IBIS model with the different extension, so you may be able to run a simulation with this model (or the original IBIS model) in a signal integrity simulation tool such as HyperLynx, or import the IBIS model into HSpice.


    Thank you for your time,
    Manuel Chavez

  • In reply to Manuel Chavez:

    Hi Manuel,

    Thanks for your response and your time.

    Hmmm. I have the free version - the Full version isn't cheap! But what I have done is simulated the output of the chip using TI digital gate, figured out the Zo and added some resistance to ~ the Zo of the 7310C.

    It is driving a short bit of coax into my scope. Results look OK but will have to build and tweak accordingly! :-)

    Not interested in simulating the input circuitry or the capacitive barrier - just the output section - hope it is reasonably close to reality!

    Best regards,

    Peter

  • In reply to Peter Partridge:

    Hi Peter,

    Of course! Digital isolators behave essentially like buffers, so using a gate and factoring in impedances should yield a usable model for your case :)

    I apologize for the inconvenience due to the lack of a model, but let us know if there is another way we can help in your analysis! Please also consider using the ISO7710 in your setup instead of ISO7310C. IISO7710is a newer isolator with improved isolation performance which can replace ISO7310C in the majority of applications.


    Thank you,
    Manuel Chavez

  • In reply to Manuel Chavez:

    Hi Manuel,

    Yes - the method I have used is working well to simulate the Output of the ISO chip.

    Thanks for suggesting the 7710 - it looks superior in many respects to the 7310C. But there is a couple of things - the minimum threshold for a high is only 0.7 x Vcc = 3.5V compared to 2V for the 7310C. This is bad for me - the input is fed from 1.5m length of 50 ohm coax that is not terminated properly - i.e. 50ohm source and 50 ohm load. I had to use a source of 10 ohm and load of 100 ohm to prevent the signal from dropping too low plus there is a momentary dip due to the mismatch. The dip sits above 2V comfortably with the 7310C BUT it would be dangerously close to the 3.5V threshold in the 7710. Why the discrepancy in thresholds?

    Also the quiescent current for the second section is very low @ 600uA compared to 1.2mA for the 7310. This is great because I want absolute minimum current for Icc2 because that part is floating and driven by a 9V battery through a micropower 5V reg.

    But, the weird thing is the ratio of Icc1:Icc2 - for the 7310C it is 0.2:1.2mA but for the 7710 it is 0.5:0.6mA. The current ratios for the 1st and 2nd sections are so different - why is that? Is it a misprint in the datasheet for the 7710?

    Thanks for your help.

    Best regards,

    Peter