- Joined
- Mar 29, 2013
- Messages
- 1,221
- Points
- 63
Hello LPF, long time no see!
It's been a good long while since i've been on here. After switching my focus to multirotors and FPV and then moving to the east coast for school, I seem to have forgotten my roots!
Well, 2+ years later i'm halfway done with my Electrical Engineering degree and looking to get back into the laser scene (oh how it has changed so much since I was last here!)
Basically, I am looking to build a lab-style 445 - 450nm tabletop laser to be used in demonstrations (working with my professor). However, as an exercise in circuit design and tweaking, I want to design my own constant current driver from scratch that allows analog control of the output power. I have completed a few semesters of analog electronics but definitely not enough for this project to be a breeze.
So i come to you guys! There's plenty of information on constant current drivers online, but as we all know, laser diodes can be more sensitive than your average load. I was hoping that some of the driver design veterans out there could point me in the right direction as to what makes a good constant current driver and what kind of specifications are important. I am assuming that you can not just pluck any buck IC from the lot and it will be suitable for driving laser diodes.
I guess the first thing I am unfamiliar with is how you take a voltage converter and then turn it into a constant current source. I am assuming that it utilizes a precision resistor inline with the load and then drives the output such that the voltage across the resistor is equal to some internal reference?
I am planning to use a step-down design (~12V input) with a max output current of around 5A (for those new beefy NUBM44 V2 diodes). Size is not a concern, and I plan to use active cooling for both the diode and the driver for continuous operation. I am looking to learn along the way here!
I am familiar with circuit design tools and circuit simulation, if that's relevant.
Any and all pointers in the right direction would be greatly appreciated!
Thanks guys, it's good to be back.
Best,
Matthew
It's been a good long while since i've been on here. After switching my focus to multirotors and FPV and then moving to the east coast for school, I seem to have forgotten my roots!
Well, 2+ years later i'm halfway done with my Electrical Engineering degree and looking to get back into the laser scene (oh how it has changed so much since I was last here!)
Basically, I am looking to build a lab-style 445 - 450nm tabletop laser to be used in demonstrations (working with my professor). However, as an exercise in circuit design and tweaking, I want to design my own constant current driver from scratch that allows analog control of the output power. I have completed a few semesters of analog electronics but definitely not enough for this project to be a breeze.
So i come to you guys! There's plenty of information on constant current drivers online, but as we all know, laser diodes can be more sensitive than your average load. I was hoping that some of the driver design veterans out there could point me in the right direction as to what makes a good constant current driver and what kind of specifications are important. I am assuming that you can not just pluck any buck IC from the lot and it will be suitable for driving laser diodes.
I guess the first thing I am unfamiliar with is how you take a voltage converter and then turn it into a constant current source. I am assuming that it utilizes a precision resistor inline with the load and then drives the output such that the voltage across the resistor is equal to some internal reference?
I am planning to use a step-down design (~12V input) with a max output current of around 5A (for those new beefy NUBM44 V2 diodes). Size is not a concern, and I plan to use active cooling for both the diode and the driver for continuous operation. I am looking to learn along the way here!
I am familiar with circuit design tools and circuit simulation, if that's relevant.
Any and all pointers in the right direction would be greatly appreciated!
Thanks guys, it's good to be back.
Best,
Matthew