I have an IoT project to monitor battery voltage. The battery is nominally 12V (car battery) and my IoT board accepts 5V input. I previously powered it just using a 5V regulator but that is not efficient and it is getting too hot. I would like to switch to something more efficient. Would something like this DC-DC converter (Mean well SPU01M-05) be what I am looking for?

I would guess I need to add some over voltage protection for the input side since the battery is charged at 13.6V and teh DC-DC converter is limited to 13.2V.

Would this be more efficient than a TO220 package regulator?

 

Go for a LM2596 pcb..

 

As @Dodgydave says, these work pretty well. And cheap too.

 

Thanks @Dodgydave . I think that is what I am looking for. I'll try it out.

 

Don't overlook obsolete car cell phone chargers (and USB adapters); most of those are just a 12V to 5V converter based on an MC34063 (or clone), good up to 1 amp. I don't know how the efficiency compares with the '2596, but they're free if you have one already (or almost free at garage sales and thrift stores), more efficient than a 7805, and designed to survive an automotive electrical environment. Motorola provided a very helpful data sheet and app note booklet for the 34063, complete with PCB layouts for up/down/inverting applications.