WEBENCH® Tools/LM3481: Boost simulation not working as expected when Vin > Vout,set

Kevin Schmidgall

Part Number: LM3481
Other Parts Discussed in Thread: TINA-TI

Tool/software: WEBENCH® Design Tools

Hello,

I am trying to simulate a boost converter with an input transient that has Vin goes higher than Vout,set (Vin = 17V and Vout,set = 15V). What I would expect to happen is the input is passed through to the output and is around 17V since 17V is already greater than your output voltage set point. Instead it looks more like the converter is still trying to boost the 17Vin. It looks like it is settling around 20V with Vin = 17V.

Is this a problem because my Vin = 17V is greater than the expected Vin range, 9-14V?

Regards,

Kevin

over 6 years ago

0 Gerold Dhanabalan - Online Design Tools over 6 years ago

TI__Genius 14455 points

Hi Kevin

While we debug the Spice model, can you please give it a try by downloading the TINA-TI model from the product folder and running the simulation with the WEBENCH recommended components? The behavior that you are expecting is correct - the Vout should be Vin - (Iload *Rdson_of_inductor) - Diode drop.

Regards,

Gerold

0 Herman Theodorus over 6 years ago in reply to Gerold Dhanabalan - Online Design Tools

TI__Genius 9775 points

Hi guys,

Since the TINA-TI product folder model seems to be ok, I'll set the resp org to WEBENCH tools for spice netlist behind WEBENCH tools.

Herman

0 Praveen Badiger over 6 years ago in reply to Herman Theodorus

TI__Expert 8365 points

Hi Herman,

We will update the latest Pspice model on the WEBENCH. We will let you know once it is done.

Thanks & Regards,
Praveen B

Power management

Power management forum

WEBENCH® Tools/LM3481: Boost simulation not working as expected when Vin > Vout,set