PWM Laser control up 1 MHz and using 0-255 steps for duty cycle power control

Hello, I have one project (experimental) using a PWM Power Width Modulation. With two channels the First one has connected 1 Laser (Cross Hair) 24 Vdc supply control 5 Vdc with a 3rd control lead/wire to receive from a PDM the attenuation and 0-255 steps in duty cycle. And the 2nd CH has connected another video Ring Light that is connected to the same PWM (Light control) is working well. The Ch1 won’t work we don’t know if because we are connecting a fast device up 1 MHz and we want to control from 0-255 steps the duty cycle. The hardware we are using over the Ch1 are:
PWM from Leimac IDGB-50M2-24-TP/IP-T-L and the Laser is from Laser Components FP-DOE-635-10MD-218-F210-24V-HS19-1MHZ
We supply all with 24 Vdc and we need to use with the PWM 2 channels One for the Camera Ring that works fine and the other channel for the Laser we have the feature with the PWM to Switch from local control or remote-control using Ethernet, if we use the local knob if we push it, we can select channel 1 or Ch2. Then we can modulate the duty cycle that generates the PWM from 0 to 100 % duty cycle to the Laser square DC 5 volts train of pulses, with this equipment we don’t have the square pulses in all the span 0-1 MHz when we step from 0-255 the knob adjustment for the duty cycle, then ONLY from 0-3 we have in certain way the operation we need to. The Laser Cross Hair (using the 3rd wire for control) dimmed the output from low to high power and if we continue stepping, we can turn from On to Off the output to the Laser.
So, we need another PWM solution. Is possible we can use Seeeduino v4.2, Arduino-compatible ATmega328 MCU development.
The Seeeduino board

I will appreciate if someone can advise on this, thank you.


I’m having a degree of difficulty following the train of thought herein; please bear in mind that your equipment and application is not very familiar from this side of the screen.

What I’m gathering is that you have a desire to generate a PWM signal having a 1MHz frequency and 8-bit (256 step) resolution.

In general, a microcontroller’s clock frequency limits the achievable combinations of frequency and resolution available from its PWM peripherals; slicing a 1MHz signal into 256 pieces implies a need for something capable of operating at 256MHz, which is well beyond the capabilities of the Mega328 and similar.

There are techniques to do that, though the options one might pick depend a lot on one’s specific interests.

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Would you mind sharing with me some techniques? My expertise is working with industrial equipment like Rockwell Automation and Allen Bradley for 37 years, equipment already designed and ready to be used, but some colleges here in my work asked me about this technical support I am not able to give them for now. The devices they acquired and wired/connected won’t work as they thought.
My degree is bachelor’s degree in communications and Electronics, but I always work with metrology/Instrumentation and PLCs/HMIs. Let me know if you can advise, Regards. And yes, they want to control one Laser (Cross Hair) using a PWM up 1 MHz our Laser use and stepping/controlling from 0-255 steps duty cycle. Wondering if this controller is already in the market we can buy and use.

Unknown to me; not my area of familiarity, and DK tends to trade more in component product than finished goods.

There are analog techniques, faster microcontrollers, programmable logic, and perhaps other approaches.

That said, I’m not sure that the request is clear among all parties; your laser appears to have a 1MHz bandwidth, so a PWM controller capable of more than 1 bit resolution at that frequency would seem excessive. For uses within the limitations of the laser itself, the seeeduino device mentioned would likely be sufficient.

For uses within the limitations of the laser itself, the seeeduino device mentioned would likely be sufficient.
I will share the Seeduino with my peers. The good news one of my partners did yesterday, my coworker installed one resistor in series output between the PWM and the interface optical FC-ISO-D High Speed Optical Module, we are using between the Laser, and we have control up 225 steps, 001-225, we are still test with a 600 Ohms 1 Watt resistor and see how far we can go. I think this is enough to continue moving forward on this project. Thank and best regards for all the efforts in this support.