IR 1W laser diode: regulated current AND regulated voltage??

Hi All,

Just bought a IR laser diode here:
One Extra High Burning Power 1000 1500mw Infrared to 5 9mm Laser Diode Gift | eBay

and they say "
Typical operation current is 1.2A
Typical operation voltage is 2.0V
Maximum operation current depends of the diode, the interval value is around 1.2A - 1.6A
Maximum operation voltage is 2.2V"

I thought that as long as the current was limited, the voltage was not relevant (as long as there are no spikes) since we have a constant voltage drop across the diode anyway?
Are they just using "Maximum operation voltage is 2.2V" instead of "Voltage drop is 2.2V"?
many thanks

Thomas

ryckmans said:

Are they just using "Maximum operation voltage is 2.2V" instead of "Voltage drop is 2.2V"?
many thanks

Thomas

Click to expand...

In this case they are the same. Diodes are current driven devices. If you put 1.2A on the diode the voltage will set automatically at +/- 2.2Volt. No need to regulate the voltage too.

Thanks a lot. They don't provide a datasheet, and when the text is unclear... it gets confusing. I was planning to use the 3.3V output from a computer PSU, and then regulate the current on that. Is this a good idea?
many thanks

Thomas

If you've got nothing else, possibly. Some computer power supplies don't like to operate with such a light load. You might have to put a power resistor on the 5V rail. 3.3V also isn't enough for a linear regulator so you might have to use the 5V rail anyway. You might want to consider an old phone charger or other wall wart instead.