Drivers with wrong output voltage

[Grix]

Does output voltage matter when it comes to laser diode drivers, as long as it's above the diode's forward voltage?

I'm thinking about using these for various builds: New 445nm laser diode driver/adjustable to 1.5A [OL-445D-1.5] - $12.00 : Zen Cart!, The Art of E-commerce

But they state "Output voltage 4,5 - 6V" and the title makes it seem like they only work for 445nm diodes.. But I could use these for diodes with a low voltage too, like reds, right? The diode will adjust the voltage itself according to current, no?

 

[lasersbee]

Only if the Driver is Current regulated....
As is stated in the link... that is a Current limited
Boost Driver that can supply up to 4.5-6V.

A Voltage Regulated driver will try to supply a fixed
amount of Voltage no matter what the load.

Jerry

 

[Hiemal]

It depends on what kind of driver it is...

With a boost type driver, the output voltage can only be HIGHER than the input voltage. If you try to put a lower forward voltage diode in there it'll run the risk of death due to overcurrent AND overvoltage.

With a buck type driver, the output voltage can be lower than the input voltage. This is also true of linear drivers as well.

For buck boost drivers, they're a combination of the above and don't really care what the forward voltage of the diode is.


Point is, be careful what you use with a boost, and with everything else, it doesn't matter as long as the current is set correctly, and your input voltage is sufficient enough.





Though, this made me think, what would happen if you had a laser diode with a forward voltage of say, 3 volts...your supply voltage was 2.5 volts, so it doesn't overcome that voltage; yet the diode still lights up, yes?

What happens when you continue to increase the current to the diode? Do the dies' leads just fry off?