Hi, I need to design a buck converter using a LM27403 or LM27402. I need to implement some features not included in the 'vanilla' examples which are generated by Webench, design spreadsheet, EVMs etc. so I want to do a transient simulation in TINA. Since I was not sure which part I would use, I downloaded the unencrypted spice models for both, and captured a basic schematic for each. In summary, the LM27402 design simulates OK, but the LM27403 design gets as far as displaying the progress bar, but sticks at 0% indefinitely. I wonder if anyone can see why?
Btw, I don't really need the current limit function (or the temperature compensation thereof) - can I disable it by tying the CS+/- and D+/- pins somehow? On this same subject, since I don't need current limit, I would rather have used the LM27402 instead of the LM27403 which seems to be a superset. However, for some reason the LM27403 is cheaper and seems to give better efficiency in Webench, all other things being equal. Why is this?
Thanks
Ian
