i have 24v cnc that generate 24v pwm and i wan to install 12v laser on it
there is post that say that we can do it with L298N motor driver
L298N is easy to get for me

ext-12v-pwr -> l298n-pwr-input
ext-12v-gnd -> l298n-gnd-input
cnc-24v-gnd -> l298n-gnd-input
cnc-24v-pwm -> l298n-ena
cnc-24v-pwr -> l298n-inta
ext-12v-pwr -> laser-12v
l298n-pwra-output ->laser-pwm
l298n-gnda-output ->laser-gnd

is it good wiring plan?

 

The language to describe circuits are the schematics. You may say, my description is simple and straightforward. It may be, but it nevertheless it is not clear what other components should be attached to each pin to make it work.
This is similar to an architect describing a house without a floor plan.

 

The language to describe circuits are the schematics. You may say, my description is simple and straightforward. It may be, but it nevertheless it is not clear what other components should be attached to each pin to make it work.
This is similar to an architect describing a house without a floor plan.

what easy tool to use

 

Even if you won’t use their PCB services, you can download the ExpressPCB free schematic capture software.
Or use a pencil and quadriculated sheet of paper will do. Forrest Mims Notebook style.

 

i have 24v cnc that generate 24v pwm and i wan to install 12v laser on it
there is post that say that we can do it with L298N motor driver
L298N is easy to get for me

ext-12v-pwr -> l298n-pwr-input
ext-12v-gnd -> l298n-gnd-input
cnc-24v-gnd -> l298n-gnd-input
cnc-24v-pwm -> l298n-ena
cnc-24v-pwr -> l298n-inta
ext-12v-pwr -> laser-12v
l298n-pwra-output ->laser-pwm
l298n-gnda-output ->laser-gnd

is it good wiring plan?

No, you can't put 24V signals intp the INT or EN pins, they're strictly TTL logic level inputs. I don't think the L298N would be suitable at all. A proper current controlled Laser driver is what you need.

 

There is also a caution about the laser polarity requirements. The last lasers that I used had the positive supply on the case and the negative was the isolated connection. I used a small DC to DC module to solve the voltage and polarity problems.