Need help with Everphotonics 808-100W-QCW

Aleksa said:

PowerMax PM3-100... That's one big puppy

You need to open it up and see what kind of driver it has.
Your goal is to modify the feedback circuitry. I honestly wouldn't touch that supply,its just so big and wonderful...
Tahmid's blog (google it) is a nice way to learn basics of SMPS. When you find out what is the driver in your supply,find a datasheet for it and look for error amplifier(or what ever feedback topology it has) and post it here so we can figure out how to mod it (if its even possible). :beer:

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Okay...I will go and see what kind of driver the PM3-100 has. I will let you know as soon as I get that information on it. Thanks so much for your help! This is all just so great!
I will also check out Tahmid's blog on SMPS.

You need to look at the diodes data sheet as the specks for CW and QCW are rather different ,

This data was taken from a coherent laser diode bar data sheet , CCP diode , same package as the one in your picture .

They may not fully relate to your diode but it shows you kinda what a QCW diode needs to be run at ( CCP diodes in data are 50W - 250W QCW)



QCW (quasi-continuous wave) operation refers to a high repetition rate, short-pulse mode of operation (e.g., 200 μs pulses, 1 kHz).

QCW products listed here are rated up to 20% duty cycle and pulses <1 ms long.



So your driver has to switch fast and clean to drive these in QCW mode

I did not see that... Listen to IonLaser,he has a point. My posts stand for CW diode mode only.

The problem with most of the power supply
designs out there is that they are constant
voltage (CV). In order to reliably drive a
laser diode, you will need a constant
current (CC). At least that is the case
with a CW laser diode. QCW I have no
idea. I imagine they are somewhere on a
continuum between CW and pulsed. Have you
been in contact with the manufacturer?

The Lightning Stalker said:

The problem with most of the power supply
designs out there is that they are constant
voltage (CV). In order to reliably drive a
laser diode, you will need a constant
current (CC). At least that is the case
with a CW laser diode. QCW I have no
idea. I imagine they are somewhere on a
continuum between CW and pulsed. Have you
been in contact with the manufacturer?

Click to expand...

Usually long pulses for QCW (Microseconds, short duty cycle), the driver I posted should be capable of doing it with some modification. The circuitry for pulsing the driver is already there, it'd just need something to give it a signal and a beefy output stage.

diachi said:

Usually long pulses for QCW (Microseconds, short duty cycle), the driver I posted should be capable of doing it with some modification. The circuitry for pulsing the driver is already there, it'd just need something to give it a signal and a beefy output stage.

Click to expand...

Thank you so much for posting that circuit. It looks really good! I noticed that it was only capable of putting out 1.5A though. How would we make something that would give us the 100A we need at the same low voltage? What are the specifications that you are going to need for the circuit that you are building?

ionlaser555 said:

You need to look at the diodes data sheet as the specks for CW and QCW are rather different ,

This data was taken from a coherent laser diode bar data sheet , CCP diode , same package as the one in your picture .

They may not fully relate to your diode but it shows you kinda what a QCW diode needs to be run at ( CCP diodes in data are 50W - 250W QCW)



QCW (quasi-continuous wave) operation refers to a high repetition rate, short-pulse mode of operation (e.g., 200 μs pulses, 1 kHz).

QCW products listed here are rated up to 20% duty cycle and pulses <1 ms long.



So your driver has to switch fast and clean to drive these in QCW mode

Click to expand...

Thanks for that information! I really appreciate how everyone is willing to help. The Coherent CCP diode bar that is 100w is basically the same as my Everphotonics package. Yes, I will definitely need to run my diode bar in QCW mode. Do you know of any circuit schematics out there of drivers that will do this and give us the max 100A and max 2.2V that we need?

Are you aware of the danger of what you are building ? I must ask,how old are you ?
Do you have any electronic experience ? Building the power supply requires a lot of knowledge. Please think this trough. Also,the supply isn't really the hard part,cooling the diode will be a major task. And optics are also going to be a tricky. Building what you want will require a LOT of money and knowledge that you don't seem to have. People here cant give you word for word solution. You need to learn all the basics first and then jump to building stuff. You cant run if you cant walk

Aleksa said:

Are you aware of the danger of what you are building ? I must ask,how old are you ?
Do you have any electronic experience ? Building the power supply requires a lot of knowledge. Please think this trough. Also,the supply isn't really the hard part,cooling the diode will be a major task. And optics are also going to be a tricky. Building what you want will require a LOT of money and knowledge that you don't seem to have. People here cant give you word for word solution. You need to learn all the basics first and then jump to building stuff. You cant run if you cant walk

Click to expand...

I am a physics student at University of North Carolina at Wilmington. I am part of a group of physics majors that is building a high power laser metal engraver using this unit.

Click to expand...

That's why I didn't mention the safety factor, I figured a group of physics majors would be able to figure it out. Cooling isn't all that difficult, either water cooling or water cooling with a beefy TEC would cover it. Getting a nice spot out of one of these, that's a completely different matter and the best way is probably to fibre couple.

Arockin, that circuit is only good for 1.5A as is, you should be able to add a FET or a bunch of pass transistors to it to do the heavy lifting. At least in theory... I haven't finished building mine as not all of the components have arrived, so it's not tested with the pass transistors yet!

Its all easy in theory,but actually building the whole thing? not that easy,been there,trust me. Not many people here are playing with such powerful lasers.
Schematic that Diachi has provided can be used as a interrupter but not as a driver. Adding fets and transistor to lover down 12v to 2.2v is not the way to go. Way to much heat dissipation. But...sense they are going to use it in QCW mode,it might be possible to get away with a few fets. Sense there will be not enough duty cycle to heat the fets. Still not a good way,not a professional way. If you are building something that is going to be used for manufacturing or being constantly used,you need a proper supply,optics,cooling etc. You can buy everything that you need. All dough it costs plenty,if you are going to use it in profitable application,money will come back
If you are just planing on experimenting,i suggest learning the whole theory of switch mode power supply's.
I wanted to build a similar machine but didn't have a clue on what lasers are and how they work. I had a presstek 40w 808nm FAP module and i didn't know anything about it. So i decided to learn the basics first and then play with the high power bars. That's is how i found this forum,all dough i didn't found out what i wanted i still managed to figure out a safe way to learn all that i needed. Go slow,go basic! Don't rush,that is one big mistake(experience talking). This forum is GREAT for learning the basics. There is a LOT of information and experiences being sheared.