LM5001 SEPIC Gain/Phase simulation using TINA-TI

Sagar Sivasankaran

Prodigy 170 points

Other Parts Discussed in Thread: LM5001, TINA-TI

Hi,

I want to simulate Gain/Phase of LM5001 SEPIC configuration.

LM5001 product page has “LM5001 TINA-TI Transient Reference Design” and it is example of BOOST converter.

Please advise

1.Transient spice model or Average spice model is required to simulate Gain/Phase?

2. I can simulate Gain/Phase of SEPIC configuration when I modify boost circuit as follows?

3. How to use the Voltage generator in feedback loop.

Best Regards,

Sagar C S

over 9 years ago

0 Alex Triano over 9 years ago

TI__Genius 12621 points

Hi Sagar,

This post belongs in the DC/DC forum. I will move it accordingly for the correct team to work with you.

Thanks,
Alex

0 Britt Brooks - Online Design Tools over 9 years ago

TI__Mastermind 41310 points

Sagar,

The Average model is required to simulate the gain/phase of the LM5001. Unfortunately, we do not have an average model for the LM5001 available currently.

The transient model should support the SEPIC configuration, but I have not checked it in that configuration.

The Bode Plot is available in WEBENCH®, but only for the boost configuration.

0 Sagar Sivasankaran over 9 years ago in reply to Britt Brooks - Online Design Tools

Prodigy 170 points

Britt,

Thank you for your quick reply.

I am trying to simulate the sepic convertor using transient model. I also requested for the Average spice model in TI Website.

Can you please provide any application note describing the Gain / Phase analysis using TINA-TI.

I am not sure how to introduce the voltage generator in the feedback path?

Also i am not able to simulate the circuit with a battery replacing the voltage generator (the battery is working fine for some other circuits).

I've upload the simulation file to googledrive.

https://drive.google.com/folderview?id=0B5e2mKfhqOVqSmhpT1F5UEZFbHc&usp=sharing

0 Nikhil Gupta (Product Folder Models) over 9 years ago in reply to Sagar Sivasankaran

TI__Mastermind 39210 points

Sagar,

Can you attach the file with this post instead? We can not open public drives due to security risks.

Thanks!

0 Sagar Sivasankaran over 9 years ago in reply to Nikhil Gupta (Product Folder Models)

Prodigy 170 points

Please find the simulation files below.

5V_LM5001 SEPIC.zip

0 Sagar Sivasankaran over 9 years ago in reply to Sagar Sivasankaran

Prodigy 170 points

Also i got a reply from TI saying that they don't make and provide average spice model.
May i go ahead with Transient spice model for Gain / Phase analysis?

0 Britt Brooks - Online Design Tools over 9 years ago in reply to Sagar Sivasankaran

TI__Mastermind 41310 points

Sagar,

Since TI does supply average models for many products, I would guess that the reply you received was inaccurate. You cannot use the transient model for Gain/Phase analysis. You can use the transient model to do transient simulations (time domain). You may get some insight into the stability of the circuit by running a load transient and observing the ringing, but that will not tell you the Gain/Phase characteristics of the device.

0 Sagar Sivasankaran over 9 years ago in reply to Britt Brooks - Online Design Tools

Prodigy 170 points

Britt,

Thanks for the clarification.

Still i want to have the average model for the analysis. I contacted tiasia@ti.com and they said "no".

Please share if you have any other contacts for the spice models.

I still have few other questions regarding the issue.

1. My SEPIC circuit is working with only voltage generator source, not with battery. Pls have a look at the below schematics?

LM5001 5V OUT WORKING_Actual.TSC

2. How to connect the voltage generator in the feedback loop for stability analysis?. Even it is not possible with LM5001 as of now, i want to use the same for my future designs. so please share any details you have regarding the same.

Simulation, hardware & system design tools

Simulation, hardware & system design tools forum

LM5001 SEPIC Gain/Phase simulation using TINA-TI