Driver with built in duty cycle?

[Cube777]

Hi LPF,

I don't have the knowledge (yet) to design something like this, but what if someone can build the usual driver like a FMT but with a built in timer to switch off the laser after it has reached it's max duty cycle "on" time and keep it off till it has cooled off, thus protecting the laser from n00bs who doesn't know what a duty cycle is. I'm sure someone here could design one, and maybe a adjustable one too? :thanks: for reading!

 

[baharini]

What sort of form factor are you looking for? A labby or portable build?.
I have a few ideas and could design one.

 

[Cube777]

i'm thinking this could work for handhelds (labby's won't need this), but I don't have a use for it yet, just throwing around some ideas.

 

[Moistenator]

It's a good idea. But it's not needed, Noobs who don't understand how to operate a laser and stick to a duty cycle shouldn't be in possession of any lasers above 5mW.

 

[Bionic-Badger]

I dunno... I could just see all the n00bs visiting this forums complaining that their laser is broken because it shuts down periodically while in use.

I also think it would be dangerous to have it turn back on once the laser has sufficiently cooled down. It ought to just shut off completely until turned on if it gets too hot.

 

[Cube777]

We could just add a note when you sell the laser saying "The laser will shut down automatically after X minutes", and I agree it shouldn't turn on automatically, you need to physically turn it off and then on again (after the cool down time is finished). Also the cool off time should only initiate if it had reached it's max "on" time, otherwise it could get complicated and annoying.

 

[Bionic-Badger]

It'd probably be better just to measure the heat and if it overheats, then shut off. Still, such a system wouldn't be worth adding to cheap lasers, and usually people with the better lasers know how to manage their on-time.

 

[Cube777]

Still it's a good backup just in case you forget.....

 

[jArdi]

How about this:
How About:
2 Switches/Click buttons, 2 LED's, + Laser diode.

Button 1: Turns on power
Led 1: Power Indicator [ON]

Led 2: Indicates Laser Duty cycle has passed, and your laser will now operate.
Button 2. Turns on LD

As the LD is on, led2 will blink. As the LD approaches the max duty cycle, the LD will blink faster or slower (either one, depending on what you want)

OR

Rather then led2 being on and saying your laser is 'armed' it can be like a 'hold' light instead. While led2 is on, you cant use it.
Of course, you can easily bypass this simply turning on/off full power, but then it will be your own fault for wrecking your LD
There are tons of combos you can do with this, all can be very simple.

A note: for anybody who doesnt feel like having 2 led holes drilled, you can easily get a click button with a multicolor light - that will indicate power, hold, armed/ready etc....

 

[Cube777]

^Very good idea..... then your not limited by the duty cycle yet there is protection for it.

 

[cheech226]

Who is going to pay an extra $50 (kinda arbitrary figure) to shut their laser off for them? there are greens that will adjust current to the pump to prevent overheating. but i think here we over complicate things for diode lasers

 

[Flaminpyro]

I rather like the idea of a temp sensor that will shut it down when it reaches a certain temp and let it be turned on when the temp drops a certain amount.

Wait a just one second we already have a driver that will do that and it's called a V5

 

[cheech226]

exactly, and that's not the only one.

 

[jArdi]

Who is going to pay an extra $50 (kinda arbitrary figure) to shut their laser off for them? there are greens that will adjust current to the pump to prevent overheating. but i think here we over complicate things for diode lasers

for the record, it will only cost like $2, total, MAX.the led is more expensive than the chip.

I rather like the idea of a temp sensor that will shut it down when it reaches a certain temp and let it be turned on when the temp drops a certain amount.

Wait a just one second we already have a driver that will do that and it's called a V5

I can implement that.

 

[Cyparagon]

Thermal switch. $1. Done.

 

[Hiemal]

Guys you do realize that nearly every driver in existence has some sort or form of thermal protection built into it?

The manufacturers of the IC's know that temperature is obviously something to keep in mind. So they often do us a huge favor by adding in overtemp sensors in the IC itself, so when it gets too hot, it starts to limit itself in some form or another, whether it be by flickering, lowering the output current...

This does the job well enough for you.

HOWEVER

If you're talking about the laser diode itself, that's something completely different...and would be kind of silly to bother implementing. Just feel the heatsink/laser diode area with the palm of your hand. If it's too hot, turn it off. Not hard.