And I felt confident this is an automotive application because TS said that in post #9.
My bad.

Not a problem because it is an automotive application OP said in post #1 that the power supply circuit was one that he found, so it's unclear if it was intended only for automotive applications.

The "problem", if there is one, is that I'm very detail oriented...

 

The "problem", if there is one, is that I'm very detail oriented...

Maybe you can partner with WBahn. He seems to be in high gear this week.

 

Should I swap the D16 zener to a TVS Diode whether or not I go with an output of 5v or 9v? If I go with 9v, which zener or TVS diode should I use?

Something with a standoff voltage higher than your operating voltage.

I rarely use TVS diodes. I've only had one power supply I built ever have a regulator go bad and it never damaged anything other than itself when it died...

 

Something with a standoff voltage higher than your operating voltage.

I rarely use TVS diodes. I've only had one power supply I built ever have a regulator go bad and it never damaged anything other than itself when it died...

Thanks! I wonder if I should just keep it simple and follow the diagram I posted in post #1.

 

Thanks! I wonder if I should just keep it simple and follow the diagram I posted in post #1.

If I was doing it, I'd drop the unnecessary components. If I was rectifying AC, I'd go with with 1N400x rectifiers as a schottky rectifier is wasted in that application.

The small value caps are ceramic and are typically placed close to the regulator.

 

That would only be true if 12V raw was around 12.4V.

Well, the 12VRAW and 12V are simply labels. I guess that the 12V label should have read "12VRAW-DIODE_DROP".

 

Well, the 12VRAW and 12V are simply labels. I guess that the 12V label should have read "12VRAW-DIODE_DROP".

Actually, the schematic creator should have just used the correct I/O designators. S/he used an input designator for the 5V output...

 

Actually, the schematic creator should have just used the correct I/O designators. S/he used an input designator for the 5V output...

Yeah, I saw that!

 

Notice the varistor at the input. I'm not too familiar with using varistors for transient surge protection, but my first impression would be that the Schottky diode is there to separate the regulator IC from the transients that the varistor is suppressing. Again, I'm not at all conversant with such circuits.

Is this schematic intended for automatic applications? Auto electrical systems are a notoriously high noise environment -- though with all of the computers and other electronics in a modern car that may be less the case now. I guess that would come down to whether it is cheaper to condition a single supply source and distribute it or to clean up and protect devices at the points where they are used.