Pulsed laser diode : Query

[elecrom]

Hello,

I have LDMP9050050 pulsed laser diode. I also have laser diode driver which can provide pulses of 100ns. This driver has two outputs terminals : +ve and GND

However laser diode has three terminals. When I looked into datasheet of PLD it says ...
1. is LD cathode
2. is PD anode
3. is PD cathode

(on the contrary our OLD PLD, of unknown number, has only two terminals)

What does it mean ? Which two terminals( possibly 2 and 3 ??) should I connect to o/p of laser driver ?

These are very expensive components and hence I don't want to proceed without taking experienced user's advice.

please help.

 

[FvM]

PD is monitor photo diode. It's usually present with CW laser diodes. From the (scarce) information you gave, I would expect, that the laser diode uses the case as a fourth terminal. If the laser diode anode would be in common with photo diode, it should be clearly said in a datasheet.

Generally you have to assure, that your driver can safely drive the diode. I would expect, that a pulsed diode could be operated without feedback through a monitor diode, but I can't know for sure. You have to check from the driver and diode specification. In any case, the laser diode allowed operation conditions have to be written in the datasheet.

 

[elecrom]

Thank you.

This is the datasheet of that PLD. **broken link removed**

We have ensured that our laser diode driver will not supply more than 50W . And pulse width will never be longer than 100ns.

 

[FvM]

I think, operation should be safe, when you keep the allowed maximum pulse current and pulse width (and repetion rate). I still don't know, why the said LD has a monior detector, that's unusual for pulse laser. May be, it exists only in the drawing, copied from a CW diode data sheet, cause the necessary sensitivity specification is missing.