Thanks for measuring that, Jufran88. It seemed weird to me that it was outputting too much current.
The LM317 does drop ~2.5v at 1.5A and 25*C.... He's running at ~100ma so it should be lower dropout, looks like ~1.7v from the graph.
The "Dropout" rating of regulators is the maximum, for...
If the diode were in backwards it would be in parallel with the LD, so the whole setup would still work as expected... well, it wouldn't protect your LD and your voltage drop would be higher, but it would lase still.
Still puzzled on the expected vs actual current output. Have you tested...
Cool, great to hear that they work.
I'm sorry if this sounds insulting, but perhaps the protection diode is on backwards?
4.5+1.2+0.7 = 6.4, so your 6.11v source wouldn't cut it.
Does seem to operate a couple volts lower than the LM317 though, how is the heat? Do you notice a difference?
As...
That is why I said it was hard to see. I was having identifying everything.
From what I can tell:
If you look at the bottom center you'll see 3 red pads.
The left two connect to resistors (for the current limiting) and the rightmost connects to the positive power through a decoupling cap. The...
Your circuit looks good, the board is harder to tell because I can't see it very well, but also looks OK to me. If it passes the DRC and ERC fine then you should be in the clear.
What's the size of the finished board if you don't mind me asking? Around 11x15mm?
As you said, your power rating...
The datasheet shows a larger (22uF) cap on the output, but a 10uF should be fine on input.
I don't know of resistors offhand, but I will need to order some as well.
Edit: Missed the point, yes 10uF is probably fine, I'll use a 22uF because I have it in inventory.
The Micrel 29312 Chip looks good to me.
The Vin(Max) is +16v with an absolute max of +20v.
Vref = 1.215-1.265 (Basically 1.25 like the LM317)
Dropout is way lower.
I'll add a couple to my digikey order for testing as well.