Hi

Can you share your favour DC to DC chip here, I can do a search, but I think it might be a good idea to start with one of your favour chips.

requirements:
Input: 40V
Output: 5V
Current: ~100mA

Thanks

 

Do you mean the IC number or modules?

 

Do you mean the IC number or modules?

I meant the IC number

 

Texas Instruments TPS40200 is a good choice for the specified requirement above. I use it with great success. This IC has a wimpy gate driver so I only use it for low power converters. It drives an external P-FET. At 100 mA and 5 volts the duty factor is low and the P-FET does not need high values of gate current. The 40200 is fine for this job. If the requirement was 2 amp or more, I would recommend a TPS40054-5 family. At higher currents this family is the choice due to improved gate current and synchronous rectification, as well as N-FET drive.

But your requirement is fine w/ non-sync and P-FET drive, so the TPS40200 is the right part.

Claude

 

I just used TI's LM5008 and was very happy with it.
Just head over to TI and use their Webench designer and out comes a schematic/parts list,etc... You can adjust for "efficiency, parts count,price",etc... it can't get any easier.

 

i have used the LTC3824 a few times

http://cds.linear.com/docs/en/datasheet/3824fg.pdf