Setting driver while "hot" with LOC red diode

[paulzimm]

Hello, I just received 3 LOC (long open can) LPC-815 red laser diodes. I have a few RKCSTR Micro-Drivers coming in the mail and I was wondering if it is possible for me the adjust the potentiometer on the driver while the laser is "hot" and running.

Since the laser diode can handle over 400mA and the RKCSTR driver can only max out at 440mA, I was wondering if I will harm anything. I have a lab-style heatsink and also a dummy load, but I want to see the difference real-time. The reason is that I may only set the driver at just over 300mA if there is no big difference in light output between that and +400mA. I just want to be sure that by adjusting it while "hot" I will not cause any voltage spikes or anything. Thank you for your time...

 

[Kookapeli]

I wouldnt suggest doing that you could kill both the driver and or diode when turning the pot you could slip and short something out on the driver but there are other reasons I'm sure someone else will explain.

 

[Toke]

I have been doing that with a labby, it looks pretty cool on the wall with a wide spot going from 100-420mA and back.

You just have to be careful with your metering method to avoid interruptions between driver and diode. The RKCSTR Micro-Driver is linear, right?
That would let you insert a multimeter in the supply to the driver.

And yes try to avoid shorting anything while adjusting.

 

[paulzimm]

Yes, from the documentation I see that it is linear:
http://laserpointerforums.com/f64/micro-drive-laser-driver-rkcstr-22553.html
"Design based around a low-dropout linear regulator IC (1117 series) in a constant current topology."

With these drivers, does the potentiometer "stop" at the max and min positions? I have seen some potentiometers that will allow you to rotate them through a full 360 degrees so you have no way of knowing when minimum and maximum values have been reached.

I have always built my own drivers using my own parts and the information from this website:
Laser driver - It can be done

Thanks people!

 

[dnar]

I have exactly your setup, if your careful it is ok. Dont push hard on the trim pot and be aware of static (use an anti-static strap).

 

[Kevlar]

With these drivers, does the potentiometer "stop" at the max and min positions? [/url]

Thanks people!

When I built my LOC with the rckstr driver I do recall it having a stop.

 

[jander6442]

This is all good for your learning curve. I remember I use to to this very thing... still do
It's one of the fun things to do in this hobby. U have to use a fine touch, but yea it's ok to do this in the combination you described.