Recent content by jbord39

Well my friend has one from you and it screws right onto my Aixiz housing (maybe it was modified). It looks just like the picture of you holding it.

Hey, I was wondering if I could buy a 405-g lens from you. I have bought the aizix housing so I just want to be able to screw the old lens off and another new lens on. Please bill me at paypal my email address, johnbordelon@yahoo.com The address is John Bordelon 865 Iris Street Baton...

It is just a diode. All the information that I have on it is: 808nm 300mW High Power Burning IR Laser Diode DIY Lab Thanks for the info, John

Hey guys, I have some A-140 diodes that I am going to hook up to their drivesr soon. My question is why are there three pins? Normally I know you only connect two, but I am wondering if the third pin can be used to protect the diode in some way? Thanks, John

Hey guys, I recently ordered a 808nm 300mW laser. I also have an old 650-g-1 lens. I am wondering if the 650-g-1 lens will be worth using on an IR laser, since it is about 150nm off. Any information is appreciated, John

No you're reading it correctly. You only use one of the op-amps on the chip.

Here is it updated for TTL. With the TTL input at 5V about 1mA will through the load. This is sufficiently low so that almost any laser diode will be "off".

Here is a pretty good shell for your current driver. It can run off of most voltages above +9V. +12V will work. R4 works as your "range" knob and R6 as your "% of range" knob. With the given values, the current changes from 0-2A as you turn R6 if R4 is turned all the way down. If R4 is...

I didn't realize you had 3 of them built already. That said it is probably not worth rebuilding. However, as transistors heat up their parameter values (beta and forward voltage for BJT's and turn on, etc for MOSFETS) will change. A lot of that circuit is basically making an op-amp for use...

Only because I have no idea how these particular drivers work. For example if they used feedback to keep their current constant but otherwise had slightly different parameter values, then running two in parallel could cause them to overload/oscillate or something. It could work totally fine...

Thanks GDB. Do you know if two zeners in parallel, pointing opposite directions across the laser diode (with Vzk~5V) would work the same way? Thanks, John

Be sure to use a power resistor. A regular resistor (smaller than a penny) will burn out. The power needs to be rated for V^2/R = 1.25^2/1.3 ~ 1 W. You could also stick a few non-power resistors in parallel.

I would not trust this circuit in sensitive applications. As the current increases the gains will change. Try using an op-amp instead.

Yes. There is a good chance running two in parallel could break them. If you are interested you could try doing this: Set the potentiometer so that you are getting close to the lowest current. Power the circuit off and measure the resistance between the potentiometers middle and (pick one)...

If you look that is a darlington transistor. The transistors are not in parallel but hooked up in a darlington configuration. A darlington pair is not a specially made device, but two NPN bjt's with collectors connected, and the emitter of the first BJT feeding the base of the second. The...