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A-140 vs. M-140 vs. H1600

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The answer is the M and H series diodes are much more efficient than the A series diodes. They have an extra bond wire and a larger die. Most all M and H diodes can hit 2W+ with a single element lens and 1.8A current.;)
I'm late getting back to this party, but that's not totally correct. There is an extra bond wire, but the die is exactly the same size. The die itself is visually indistinguishable between all 3 types. The submount is a little different, the die itself is not.
 

DTR

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I'm late getting back to this party, but that's not totally correct. There is an extra bond wire, but the die is exactly the same size. The die itself is visually indistinguishable between all 3 types. The submount is a little different, the die itself is not.
Are you sure? I was going off what Blord said and his picture seems to shot that it is.:thinking:


4] The H1600 has a larger die, the black base is bigger than the A-140.
 
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The answer is the M and H series diodes are much more efficient than the A series diodes. They have an extra bond wire and a larger die. Most all M and H diodes can hit 2W+ with a single element lens and 1.8A current.;)
That extra bond wire is not part of the anode nor cathode, and serves no
additional function for current delivery. Now if there were 2 additional routed
to + / - points of the die, you could safely assume that more current could be
delivered. Though in this case its not.

Also, as PBD pointed out, its the submount which is larger, not the die.. The submount
is the larger square pad which the die is mounted to. The die itself is the long
thin line running down the center. The only other difference I would assume is
possibly a slight increase in the flow of heat into the body of the diode.

In neutral ground diodes, the submount is only thermally conductive, so in this
case, it being larger, will also not have any affect on power to the die..


EDIT* Just to save confusion, I was referring to the 'extra' bond wire to the single
extra, I misread the quoted post as if you were referring to that one. Need to read 3x
when posting at such a late hour.. :undecided:
 
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That extra bond wire is not part of the anode nor cathode, and serves no
additional function for current delivery. Now if there were 2 additional routed
to + / - points of the die, you could safely assume that more current could be
delivered. Though in this case its not.

Also, as PBD pointed out, its the submount which is larger, not the die.. The submount
is the larger square pad which the die is mounted to. The die itself is the long
thin line running down the center. The only other difference I would assume is
possibly a slight increase in the flow of heat into the body of the diode.

In neutral ground diodes, the submount is only thermally conductive, so in this
case, it being larger, will also not have any affect on power to the die..

A diodes have 3 anode and 3 cathode wires.
M diodes have 4 anode and 4 cathode wires.
H diodes have 4 anode wires, 4 cathode wires, and a 9th wire that attaches to a square component on the submount, essentially wired in parallel to the diode. My guess is a Zener diode for reverse bias protection? Total wild guess though.


A diodes have a unique submount (among the 3). H and M diodes have the same submount, you can see the prepared area on the M submount where the square component would sit.
 

BShanahan14rulz

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Well, I'm glad that got sorted out. Thanks Blord for providing pics, and PBD for the extra pics and terminology. So the differences in performance could purely be a more perfect crystal growth or just tweaking the "formula" a bit, not just a wider "lane" for supplying more current.

So now our laser diodes are being packaged with an integral ESD protection component? I wonder if this is the main reason why LEDs are more robust than laser diodes, or if LEDs are just inherently tougher by design. Either way, all it can do is help us, eh?
 

foulmist

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So I have a couple of A diodes, would 1.6A be safe for these or should I go lower? Thanks!
Tom I have been running my A-140 at 1.75A for lots of time now. Still Lasing and Working Great. It depends on the efficiency though. You might kill some at 1.75A if it's not a very efficient one.

I think 1.6A is a good choice even for the not so efficient ones.
 

Blord

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I wouldn't run an A140 at 1.6A. I use this rule of thumb of max current:

A140 3 wires to die, 1.4A
M140 4 wires, 1.8A
9mm diode 5 wires, 2.2A

Each wire counts for 450mA :)
 

lazeerer

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So I have a couple of A diodes, would 1.6A be safe for these or should I go lower? Thanks!
You are Completely fine running them up to to 1.8A.

We All use to run these at 1.8A before the M-140.

However they where just not All efficient so some at 1.8A would do 2W and other would only do 1.6W. "Just an Example"


It you want to play it extremely safe bin your diodes and match the currant to there peak power and average.


If you dont want to do that Just Keep it at 1.7A and you will be OK.

Just keep in mind if at 1.7A with a G1 lens if you are not getting over 1.6W-1.7W your diode is not that efficient and it might be a good idea to turn it down a little more to 1.6A - 1.5A.

1.6A your pretty much in the clear and no worries about killing your diodes.
 
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tsteele93

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Thanks, I am doing a couple of A-series builds for a friend and wanted to build them safe and reliable more than raw power, but I also happen to have a couple of 1.6A drivers already built. So that would make it easier for me if I can just use these.

One of them is Tom's (Foulmist) FMT drive, so I will give it a shot. I'm gonna rob the 1.62A Mohgasm out of my 2.15W Stainless build in my sig for the other A and use a 1.75FMT in my Stainless build and see if I can crack 2.3W with it...

I'll let everyone know how it goes.
 
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planters

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The 9mm only has 4 wires on one side with 5 on the other side. The fifth is thought to lead to an ESD protection diode. I believe the max current limit for the M series and the 9mm are the same based on the wires, but the larger heat flow from the 9mm copper flange probably reduces the heating and allows higher power levels.
 

rhd

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It has been over a year since I've built a laser....but it's time for one more build :)

I have been disconnected from the scene for some time now. Who is a current trustworthy source to go to for a diode? I am looking to source one of these diodes that can hit 3.5W.
 




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