Connecting laser diode to a driver

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I’m attempting to connect an infrared laser diode to a laser diode driver circuit. I’m inexperienced with electronics and am having difficulty interpreting the technical information of my parts.

The laser diode is a ARIM ADL-78051TL. Its datasheet is available here.

The driver circuit is a iC-WK iCSY WK2D. This component seems to be part of a series, and has two datasheets. One specific to this version here, and one that details how the chip on the circuit works here.

My first questions concern how these parts should be connected to each other. I’ve compiled diagrams from the datasheets to illustrate my questions:

As is visible in the image, I don’t understand what “common pin laserdiode” and “2” are meant to connect to. Googling “common pin” indicates it has some relation to ground, but I didn’t find a definitive answer. I suspect that the “2” pin on the laser diode is meant to go to ground, since pin 1 is for the photo-diode and pin 3 is for the cathode, but the datasheet doesn’t explicitly mention this.

My other questions are concerned with the amount of voltage demanded by the diode and supplied by the driver. I’ve created a diagram with some tables from the datasheets, where I’ve highlighted the rows my questions are about:

My first question concerns supply voltage, with the relevant information highlighted in red. The driver seems to be supplying any diode connected to it with 2.4V to 6V, depending (I think) on how much the regulator on the driver has been adjusted. The diode datasheet mentions that the diode will only work with a voltage up to 2.2V.

Will this mean I need to reduce the driver’s output voltage by at least 3.8V, to ensure the diode isn’t damaged?

My second question concerns operating current, and has it’s relevant information highlighted in blue. The driver datasheet mentions it can supply a current up to 90mA. The diode datasheet indicates a maximum permissible current of 40mA. My understanding is that If I correctly limit the voltage to 2.2V, I won’t have to worry about too much current. Is this correct?

I hope that I’ve stated my questions in a clear and understandable manner, and would be overjoyed if any of you can help me.laserlaser-driverShareCiteEditFollowFlagasked 4 hours agolars1111 bronze badge New contributor

• your laser diode question is interesting and clear, but not understandable to me, because I understand infrared but not laser diodes. (1) Perhaps I can do some quick and dirty research this morning, and see if I can then understanding something. (2) I am not trying to give an answer for now. Because I cannot upload images as comments here, so I am cheating by putting image into my fake answers below. – tlfong01 1 hour ago   

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Question

1. What is the appropriate voltage to power the laser diode ARIM ADL-78051TL?
2. What is the appropriate current for its diode driver?
3. How can the laser diode and its driver connected together?

Answer

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Discussion Notes

1. your laser diode question is interesting and clear, but not understandable to me, because I understand infrared but not laser diodes. (1) Perhaps I can do some quick and dirty research this morning, and see if I can then understanding something. (2) I am not trying to give an answer for now. Because I cannot upload images as comments here, so I am cheating by putting images into my non answer here. –

/ to continue, …

References

(1) Laser ARIM ADL-78051TL Laser Diode, 25 mA, 1,8 V, 785 nm, Ø 5,6 mm Product Sheet – Reichelt, €6

(2) Laser Diode ARIM ADL-78051TL, 25 mA, 1,8 V, 785 nm, Ø 5,6 mm Data Sheet – Reichelt

(3) Laser Diode Evaluation Module, Laser Diode Driver, Integrated Reverse Polarity Protection, IC & Laser Diode – Newark

(4) Laser Diode Driver iC-WK BMST WK2D Datasheet – icHaus, Laser Components

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Appendices

Appendix A – Laser Driver Schematic

/ to continue, …ShareCiteEditFlagedited 12 mins agoanswered 1 hour agotlfong012,56311 gold badge77 silver badges1616 bronze badges

• ×Comments on locked posts are not eligible for votingtlfong01 – Hi, Please join me in the private chatroom here: chat.stackexchange.com/rooms/132856/… Thanks. – SamGibson♦ 11 mins ago

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