Hello, is there a reference design or design calculator that can be used as a sanity check for the MPQ8643?
We are planning to use this for a 12V to 0.9V converter but the datasheet has no reference schematic with component values for any output voltage and there seems to be no reference design/eval kit available.
Thank you
Hello,
Unfortunately, there is not a reference design that we have for the MPQ8643 where Vout = 0.9V.
There are the calculations as specified in the datasheet for component sizing verification. As long as your schematic looks somewhat like the following aligning with the following pin functions as seen pn page 4 of the MPQ8643 datasheet you should be ok:
If you have need for a further sanity check, you can run a simulation of the MPQ8643 using the MPSmart Simplis Software. In order to get the file, go on this page and scroll down to Design Resources to get the MPQ8643 Simplis file using the following link:
To get the MPSmart Simplis software, use the following link for download:
MPSmart | Design Tools | MPS | Monolithic Power Systems
Hope this helped. If you have any more questions, please reach out.
Best,
Krishan
Thank you for the quick response.
I am not specifically looking for a 0.9V solution in the datasheet, but any reference schematic with component values so I can double/sanity check my math when I use the datasheet when I do my own design.
I noticed that this part is basically the MPQ8633B with better specifications but the same architecture so is it possible to use its evaluation schematic ( EVQ8633B-LE-00A) or the MPQ8633B online calculator (DC DC Designer Online - Design Tools - Design) as a starting point for a MPQ8643 design?
Unfortunately, there is not any reference schematic with values on either datasheet for both parts that you have mentioned. However, there is a reference schematic with values on the DC/DC Designer tool for the MPQ8633B.
Yes, looks like the MPQ8643 has similar specs and the same package type, so they should be interchangeable for your application. Since you are deferring to the MPQ8833B for simulation purposes, then using the DC/DC Designer tool is a solid choice in judging the performance of the MPQ8643 in this case because of the similarity of these parts.
Note the only difference between the MPQ8643 and the MPQ8633B in terms of external connections would be the C_OL capacitor between the FB and RGND pins in this case, so these minor differences with this part in your model should be accounted for.
However, if you are still going to use the MPQ8643, I would see the differences between the simulations for the MPQ8633B if you truly want an accurate simulation for the sake of having a sanity check. But these differences should be minimal.
Hope this helps,
~ Krishan
