Compilation Of Information (First Major Build)
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Toaster
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Re: WIP Complete Laser Creation Tutorial
Diode Testing
Redundant additional video.. I am just videoing my learning
Pt1
Pt2
Diode Testing
Redundant additional video.. I am just videoing my learning
Pt1
Pt2
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HIMNL9
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Re: WIP Complete Laser Creation Tutorial
Diode voltage dropout depend from the material of the junction, the type of diode (rectifier, schottky, avalanche, tunnel, and so on), and from the current that is passing through them (and the temperature of work) .....
Basically, is assumed that all standard silicon rectifier diodes have a medium dropout of 0,75V (but this only at low currents, typically 50 to 100mA) ..... this can change a bit, anyway, with the current rising .....
1N400x serie (1A silicon rectifiers), as example, have a dropout curve like this:
Good til 500mA, but over this limit, not too much suggested (also cause it start to heat a lot
)
diodes like 1N540x and BY255 (3A silicon rectifiers) and BY500 serie (5A silicon rectifiers) have dropout curves like these ones (BY500 curve is practically identical to BY255 one):
1N540x
- BY255
More stable at higher currents, ofcourse ..... and still perfectly working at low currents
Also, if you need a "medium step" for get the needed value, you can add to your serie a 5A schottky diode (like SR5100 or any other equivalent), cause for their internal construction, schottky diodes have a minor dropout than standard silicon diodes, usually in the range of 0,4V ..... this is not indispensable, but can be useful, as example, if you have to test a specific low-voltage driver for laser diodes with low dropout, like power IR ones .....
Diode voltage dropout depend from the material of the junction, the type of diode (rectifier, schottky, avalanche, tunnel, and so on), and from the current that is passing through them (and the temperature of work) .....
Basically, is assumed that all standard silicon rectifier diodes have a medium dropout of 0,75V (but this only at low currents, typically 50 to 100mA) ..... this can change a bit, anyway, with the current rising .....
1N400x serie (1A silicon rectifiers), as example, have a dropout curve like this:
Good til 500mA, but over this limit, not too much suggested (also cause it start to heat a lot
)diodes like 1N540x and BY255 (3A silicon rectifiers) and BY500 serie (5A silicon rectifiers) have dropout curves like these ones (BY500 curve is practically identical to BY255 one):
1N540x
More stable at higher currents, ofcourse ..... and still perfectly working at low currents
Also, if you need a "medium step" for get the needed value, you can add to your serie a 5A schottky diode (like SR5100 or any other equivalent), cause for their internal construction, schottky diodes have a minor dropout than standard silicon diodes, usually in the range of 0,4V ..... this is not indispensable, but can be useful, as example, if you have to test a specific low-voltage driver for laser diodes with low dropout, like power IR ones .....
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Re: WIP Complete Laser Creation Tutorial
Good work, man. You should link the diode compilation thread on the diode section for more information. Also, Drew at modwerx.com sells chargers for less money: Battery chargers : Modwerx Shop (he's out of stock right now but I think he'll be getting some more soon).
Good work, man. You should link the diode compilation thread on the diode section for more information. Also, Drew at modwerx.com sells chargers for less money: Battery chargers : Modwerx Shop (he's out of stock right now but I think he'll be getting some more soon).
HIMNL9
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Re: WIP Complete Laser Creation Tutorial
Yes, basically, for our use in test loads, you can considerate them 0,7 / 0,8V, it's not too much important in this case ..... just use 1N400x serie for currents til 500mA, and 1N540X / BY255 / BY500x serie for high current loads (or, more simple, just build a test load using directly 3A or 5A diodes, they works good for high currents and also better with low currents, so you don't need to build 2 of them
)
After all, (but you probably already know this), diodes in the test load are used for simulate a "real laser diode" load type, with its own dropout voltage, so the setting of the load can be done with a load that try to reproduce in the more accurate possible way the dropout of the real laser diode, and in this way you can check if, with that type of load, the driver work good ..... so, you don't need a super-precision in dropout simulation, just to get a value close enough to the laser diode that you want to use .....
Just for give an example, imagine to use a boost drive with a maximum output voltage of 5V ..... if you use it with a red laser diode, it's ok, if you use it with a BR diode with 6V FV, it don't work correctly ..... but if you set up the driver with a pure resistive load, or with a load that don't have a dropout similar as the BR diode, your driver works good during the set up process, and you find it non working correctly only after, when you have already soldered it on the laser diode .....
Yes, basically, for our use in test loads, you can considerate them 0,7 / 0,8V, it's not too much important in this case ..... just use 1N400x serie for currents til 500mA, and 1N540X / BY255 / BY500x serie for high current loads (or, more simple, just build a test load using directly 3A or 5A diodes, they works good for high currents and also better with low currents, so you don't need to build 2 of them
)After all, (but you probably already know this), diodes in the test load are used for simulate a "real laser diode" load type, with its own dropout voltage, so the setting of the load can be done with a load that try to reproduce in the more accurate possible way the dropout of the real laser diode, and in this way you can check if, with that type of load, the driver work good ..... so, you don't need a super-precision in dropout simulation, just to get a value close enough to the laser diode that you want to use .....
Just for give an example, imagine to use a boost drive with a maximum output voltage of 5V ..... if you use it with a red laser diode, it's ok, if you use it with a BR diode with 6V FV, it don't work correctly ..... but if you set up the driver with a pure resistive load, or with a load that don't have a dropout similar as the BR diode, your driver works good during the set up process, and you find it non working correctly only after, when you have already soldered it on the laser diode .....
Toaster
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Re: WIP Complete Laser Creation Tutorial
I am seeming to have a hell of a time Making a test load.. Some thing Isn't working on my set up, either the drivers are shit, or the test load is messed up some how. I will post what I got later, Got to go to my classes.
I would, but its very incomplete and it only has Blu-ray diodes and 2 reds. Not even the 445nms.
Yes, basically, for our use in test loads, you can considerate them 0,7 / 0,8V, it's not too much important in this case ..... just use 1N400x serie for currents til 500mA, and 1N540X / BY255 / BY500x serie for high current loads (or, more simple, just build a test load using directly 3A or 5A diodes, they works good for high currents and also better with low currents, so you don't need to build 2 of them
After all, (but you probably already know this), diodes in the test load are used for simulate a "real laser diode" load type, with its own dropout voltage, so the setting of the load can be done with a load that try to reproduce in the more accurate possible way the dropout of the real laser diode, and in this way you can check if, with that type of load, the driver work good ..... so, you don't need a super-precision in dropout simulation, just to get a value close enough to the laser diode that you want to use .....
Just for give an example, imagine to use a boost drive with a maximum output voltage of 5V ..... if you use it with a red laser diode, it's ok, if you use it with a BR diode with 6V FV, it don't work correctly ..... but if you set up the driver with a pure resistive load, or with a load that don't have a dropout similar as the BR diode, your driver works good during the set up process, and you find it non working correctly only after, when you have already soldered it on the laser diode .....
I am seeming to have a hell of a time Making a test load.. Some thing Isn't working on my set up, either the drivers are shit, or the test load is messed up some how. I will post what I got later, Got to go to my classes.
I would, but its very incomplete and it only has Blu-ray diodes and 2 reds. Not even the 445nms.
Morgan
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Re: WIP Complete Laser Creation Tutorial
Look Toaster, a couple of points that I hope are helpful:
If you're going to make a video, allow the viewers to see the correct image, not a mirror image. It may be useful to YOU whilst filming but useless to us.
If you're going to make a tutorial thread, make it an efficient tutorial thread for others to watch and learn from your knowledge; not a thread where we watch YOU get tutored. This could run for an infinite amount of time whilst YOU continue not to get it!
A resistor doesn't have an anode or cathode! These things are electronics basics. Learn this stuff elsewhere and come here to build lasers when you understand. There are plenty of sites to learn these basics. Use them please.
I don't think this is contributing. I think it is leeching.
M
Look Toaster, a couple of points that I hope are helpful:
If you're going to make a video, allow the viewers to see the correct image, not a mirror image. It may be useful to YOU whilst filming but useless to us.
If you're going to make a tutorial thread, make it an efficient tutorial thread for others to watch and learn from your knowledge; not a thread where we watch YOU get tutored. This could run for an infinite amount of time whilst YOU continue not to get it!
A resistor doesn't have an anode or cathode! These things are electronics basics. Learn this stuff elsewhere and come here to build lasers when you understand. There are plenty of sites to learn these basics. Use them please.
I don't think this is contributing. I think it is leeching.
M
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Toaster
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Re: WIP Complete Laser Creation Tutorial
Yeah Yeah Yeah I know, I say A lot of stuff I dont mean. Lol Diodes do though I am asking things so I can make sure I get it right. And I will mirror it back out. For the real videos I am going to use a real camera (HD) So dont worry
Yeah Yeah Yeah I know, I say A lot of stuff I dont mean. Lol Diodes do though
I am asking things so I can make sure I get it right. And I will mirror it back out. For the real videos I am going to use a real camera (HD) So dont worry
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Toke
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Re: WIP Complete Laser Creation Tutorial
I can't come up with any other explanation either.
Yes, it is clearly the drivers.Yeah Yeah Yeah I know, I say A lot of shit I dont mean. Lol Diodes do though
I can't come up with any other explanation either.
Morgan
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Re: WIP Complete Laser Creation Tutorial
@ Toke - Do you do sarcasm over there in Copenhagen? I SO hope you do....
M
Yes, it is clearly the drivers.
I can't come up with any other explanation either.
@ Toke - Do you do sarcasm over there in Copenhagen? I SO hope you do....
M
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