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TPS7A4501-SP: TINA TI simulation VS Spice for TI simulation

Part Number: TPS7A4501-SP

Dear TI community,

I am currently studying the TPS7A4501-SP stability with bode plot of TINA TI and Spice for TI (with the Worst case analysis model).

Before trying to really study the stabilization, I'm trying to understand how bode plots are generated within the two software, since differences can be notice.

I join the screenshots of the two circuit as well as the simulation for each software. It can be seen that the two circuits are exactly the same.

From the simulations, here is what we can analyze:

The two DB magnitude plot are the same for both software, but the issue comes from the Phase plot..

As you can see, the curve shapes are the same, but the curve from TINA TI is kinda "shifted" so that the curve is centered around 0°, while the curve from Spice is centered around approximately -400°.

Moreover, if we look at the values of the phase margins (for Spice, it can be seen on the bottom of the plot) we can see that:

-Phase margin of TINA TI = 28.41 (Computed simply as Frequency value when DB curve = 0)

-Phase margin of Spice = -151.61453 (computed as Frequency value (when DB curve =0) + 180

-> Actually, if we compute -151.61453 + 180 = 28.38, which is the same than the Phase margin for TINA but we can see that the graph is shifted more than 180° compared to the graph of Pspice. So I can't

really understand the relationship between these two values.

Now if we look at the Gain margin, we can see that Pspice finds -60 (computed as 0 - Gain(when phase margin curve = -180°) while TINA doesn't find the Gain margin! The explanation is that TINA TI is 

also looking for the Gain value when the Phase crosses -180°, but since the graph is shifted, the phase never crosses -180°, so TINA says: "Gain margin not found".

My stability requirements are: 50° of phase margin and 6dB of Gain margin. The Phase margin and Gain margin values of my two analysis seems completely out of range since the circuit is quite simple.

From now, I don't now how to tune my circuit since I can't really understand which tool is the more reliable and how exactly the two software are doing the analysis.

That would be awesome if you could help me understand how to reliably perform the analysis. 

Thank you in advance for your answer. I'm available if you need any extra information.

Kind regards,