Add laser for duet2 wifi

yaman

@EasyTarget
thanks for your replay
I like to buy circuit then make one
I found everywhere I look this things
1- PWM Laser Power Output Regulator/Frequency&Duty Adjustable

2-EleksMaker PWM To TTL Transition Module

My laser is PWM and TTL
so any suggestions ?

EasyTarget

@yaman said in Add laser for duet2 wifi:

I like to buy circuit then make one

I can appreciate that

I found everywhere I look this things
1- PWM Laser Power Output Regulator/Frequency&Duty Adjustable

This is not what you want. It is a standalone controller for when you are using the laser on a bench etc. It creates the PWM/ttl signal itself. The specs say it has a serial control (but I don't see that in the pictures) which could make it useful for some cnc stuff. But not for the Duet; serial control is nowhere near fast enough for our use.

2-EleksMaker PWM To TTL Transition Module

This looks more like it! so long as it can be driven from a 3.3v input. The eleksmaker controller is 5v, but this adaptor might be fine with 3.3v too. If so, it looks like exactly what you want.

its late here, I'll try and find time to look at this properly (find the circuit or something) before Monday.
in the meantime here is a thread that may prove educational about this module:
https://github.com/openfab-lab/toolsDocs/issues/13

My laser is PWM and TTL

That is also good to know, it means the 'PWM pin should be properly driven both high and low (TTL PWM) for best results. Non TTL PWM only pulls the pin low, it has to be pulled back high by a resistor and for this reason can be a little bit less precise in timing; I've seen this discussed to death in CNC forums.
This explains things nicely too.

so any suggestions ?

If you have money to burn, order one of those modules so that it is on the way.. I'm pretty sure it is a good plan but wont be held responsible if not.

PS: Nederlands?

nicolasdb created this issue in openfab-lab/toolsDocs

open laser module TTL vs PWM #13

yaman

@EasyTarget said in Add laser for duet2 wifi:

Nederlands

Ok let's burn some money and see if will work

EasyTarget

@yaman Sorry for not getting back earlier, I still think this card will suit your needs.

I've just spent all week fitting a 32bit 3.3v controller to my cnc/laser rig (not a Duet, something based on a 7 Euro ESP32 NodeMCU module) , this and the above discussion has me a bit over-focused on laser driving from 3.3v. systems.

The laser on my upgraded rig is a 5.5W unit with a pure TTL input. I'm lucky, it can simply be wired to my controller directly; the float voltage on this pin (measured) is 3.27v, and it is high-impedance meaning it does not absorb or supply any real power, it simply follows the voltage. Switch on voltage is around 1.5V . I can simply connect this to the relevant pin of the ESP module.

I'm also going to put my 8/15W unit into a new machine with a big bed (fabric/leather cutting and decorating is the main goal) but have not worked out the specifics of this yet, it's somewhat low priority, and whatever I do will be a full custom solution. For your application I think a unit like you are getting is ideal.

yaman

@EasyTarget
thanks for reply
II am Waiting for my shipping to arrive (right now in SHANGHAI, Arrival at outward office of exchange)
and I wish you luck with your project with ESP32
until it's arrive I want to know
is there any specific command i have to add to connect the laser in config file ?

yaman

@EasyTarget
@dc42
so after Received the part and test
it won't work
it's just convert PWM to TTL ONLY
the DC plug it's just for test the Laser If it work or not

so we back to Square 0

Right now I thinking to use mosfet Or make the the 74HCT02D

Danal

I know you want to buy a circuit... nonetheless, you might want to try this, it can be built for a few cents, and no board:

Note the original diagram shows 13V in. 24V in (from the heater 6 connector) will require NO changes.

It also shows 3.3V out. For five volt out, change the 150K and 39K in the lower right to 100K and 100K.

This is "old school" analog conversion. It will not make the signal any cleaner, but it won't make it any worse, either, in that nothing in that diagram has a limited switching speed.

yaman

@Danal said in Add laser for duet2 wifi:

e the original diagram shows 13V in. 24V in (from the heater 6 connector) will require NO changes.
It also shows 3.3V out. For five volt out, change the 150K and 39K in the lower right to 100K and 100K.

thanks Danal for your Replay
I think this circuit is easy to build
here you can see the change I make for heater 6-7

analog conversion.jpg

EasyTarget

@yaman said in Add laser for duet2 wifi:

so after Received the part and test
it won't work

I'm sorry for putting you off-course with this, I see what you mean about the DC power port being for testing; I'd assumed that was the principle power port, my apologies.

Your values and @Danal 's circuit look much more suitable. And easy to source all the parts for.

For reference in this thread: I just drew up the circuit I plan to drive my similar 15/8w diode laser module from a 3v3 controller (esp32 based) .
I will use an optocoupler, I have some at home already; the basic circuit looks like:
opto.out.jpg
The OutputLimiter resistor is probably being over-cautions, the 4n35 can take 100mA/30v, but the laser module might provide enough residual power on the PWM lines to make it a good idea.
(Edit; I just looked at my circuit, I refer to 'nagative' values, probably a faux-pas, not a typo.]

Danal

@EasyTarget circuit also looks quite good. More "standard" way in the digital world...

Danal

@yaman Yes, your modifications to the values are correct. Solder it up, wrap it in tape, and give it a try.

yaman

@Danal
here are the complete drawing between Laser ; header and the circuit
do I need to add anything else

yaman

@EasyTarget
never mind it's only 10$

EasyTarget

@yaman said in Add laser for duet2 wifi:

here are the complete drawing between Laser ; header and the circuit
do I need to add anything else

Looks good to me; I was going to suggest a switch but I see you have that covered.

Danal

Looks correct, and the values given will work with a Duet (expansion) at 12V or 24V.

As with any project, verify as much as possible with a voltmeter or o-scope, every step of the way.

yaman

@Danal
@EasyTarget
OK so after some work with solder
the circuit not work exactly but after I make little change the Laser finally work

2019-10-27 16.26.43.jpg
youtube for Laser Test

https://www.youtube.com/watch?v=1KxYv2g96GY

EasyTarget

AhHA! a 10V pwm input. Same as mine; when I was looking at this last year I'd noted that 10V pwm/analogue seems to be a bit of a standard in the laser world. It's common in many CO2 lasers.

hector

Something like this would work?

https://www.amazon.com/Voltage-0-100-Linear-Conversion-Transmitter/dp/B00U7GJDVO

alt text

connected to a fan or heater, take the pwm at 24v and transform it to 0-5V DC

yaman

@hector
thanks for you replay
but this circuit will not work in my case because I don't have Fan 2
fan 2 I use it for tool 2
I have heater 6 -7 with 5v PWM

https://forum.duet3d.com/assets/uploads/files/1570300649740-laser_cable_2.jpg

Danal

@yaman said in Add laser for duet2 wifi:

after I make little change the Laser finally wor

Sounds like that laser wants 10V in.

Some want 5V (TTL), some want 10V. The two versions of the circuit above will work for the respective cases.