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# Diodes Compilation - All Diodes Data In One Thread!

#### Mohrenberg

##### New member
I've got the BDR-205 (12x), the 6x GGW, and the LCC red harvesting videos....Still need to edit and what not.....kinda buys with this thanksgiving sale and trying to get rid of the rest of these "police" builds.

#### nikokapo

##### 1
I've got the BDR-205 (12x), the 6x GGW, and the LCC red harvesting videos....Still need to edit and what not.....kinda buys with this thanksgiving sale and trying to get rid of the rest of these "police" builds.
Take your time, thanks for all the help

#### Mohrenberg

##### New member
My laserbee will be here in a week or two also....it shipped on the 23rd.

So i can start graphing diodes...

which brings up a question...I know you can hook the 1ohm resistor in series with the diode and measure the current that way, But will the diodes output be the same with that 1ohm resistor as it would without it?
and will the voltage be the same? wondering if i can measure current, voltage and output power all at the same time

#### cracked

##### New member
My laserbee will be here in a week or two also....it shipped on the 23rd.

So i can start graphing diodes...

which brings up a question...I know you can hook the 1ohm resistor in series with the diode and measure the current that way, But will the diodes output be the same with that 1ohm resistor as it would without it?
and will the voltage be the same? wondering if i can measure current, voltage and output power all at the same time
With a Vf of 6V (blu-ray), diode current drops about 3mA and voltage about 3mV. Divide those numbers by 2 for a Vf of 3V.

#### cappernicus

##### Member
Does anyone know for sure what wavelength the LPC diode is? I've looked, and I have found several different sources that claim it is 660nm, and several others that say it is 650nm...

#### Mohrenberg

##### New member
I was plotting a phr diode just now.....and when it was only at 83mW @ 131mA, i decided since it was so inefficient i wouldh push the diode.....i'm waiting to hook the setup back up to a test load so i can see what i was drving it at...(i never checked that far ahead...)

anyways, i pushed the PHR up to 243mW, with a closed-back acrylic lens! and it didn't die.....i just had to stop cause i couldn't push it any farther!! lol i know the setup pushes between 400-450mA

Dave always runs into this also.....i think diodes can withstand a LOT more current if they are slowly pushed up as opposed to being hit with tons of current

#### nikokapo

##### 1
I was plotting a phr diode just now.....and when it was only at 83mW @ 131mA, i decided since it was so inefficient i wouldh push the diode.....i'm waiting to hook the setup back up to a test load so i can see what i was drving it at...(i never checked that far ahead...)

anyways, i pushed the PHR up to 243mW, with a closed-back acrylic lens! and it didn't die.....i just had to stop cause i couldn't push it any farther!! lol i know the setup pushes between 400-450mA

Dave always runs into this also.....i think diodes can withstand a LOT more current if they are slowly pushed up as opposed to being hit with tons of current
That is great, maybe we could plot "Blasted With Current / Linearly current fed" graphs if you have some data about them.
Moh I really have to thank you for everything you're doing for this thread, thanks man

Does anyone know for sure what wavelength the LPC diode is? I've looked, and I have found several different sources that claim it is 660nm, and several others that say it is 650nm...

As per the official datasheet, the wavelength should be 660nm, though the tolerances are +4 -6nm

#### Mohrenberg

##### New member
i'm using a modified rkcstr driver.
I got 2x 8 button switches, on the fist one i have resistors that increase the current around 5mA, on the second one i have resistor that increase it around 50mA

so i flip them one by one going up about 5mA at a time, once the first switch has all 8 turned on, i turn them all off and flip one of the 50mA switches, and then start going again at 5mA at a time....and so on.
i can can go ~5mA intervals up to around 450mA
i just put it up to the test load and testes each combination i would be going trhoguh and wrote down the current that came up on a peice of paper, and then hooked the diode up and went down the list writing the output next to the current....
I'm not sure how accurate that is...

If i put a 1 ohm resistor in series with the diode and measured current, would it still be outputting the same amount as if the 1 om wasn't there???? cause i'd like to measure current and power in real time on the actual load......and i could also measure voltage at the same time.

Okay...i put it back up to the test load, it maxes out at 340mA, so the PHR was outputting 243mW at 340mA..lol i thinkt nhats the highest i've had a phr.

#### nikokapo

##### 1
i'm using a modified rkcstr driver.
I got 2x 8 button switches, on the fist one i have resistors that increase the current around 5mA, on the second one i have resistor that increase it around 50mA

so i flip them one by one going up about 5mA at a time, once the first switch has all 8 turned on, i turn them all off and flip one of the 50mA switches, and then start going again at 5mA at a time....and so on.
i can can go ~5mA intervals up to around 450mA
i just put it up to the test load and testes each combination i would be going trhoguh and wrote down the current that came up on a peice of paper, and then hooked the diode up and went down the list writing the output next to the current....
I'm not sure how accurate that is...

If i put a 1 ohm resistor in series with the diode and measured current, would it still be outputting the same amount as if the 1 om wasn't there???? cause i'd like to measure current and power in real time on the actual load......and i could also measure voltage at the same time.

Okay...i put it back up to the test load, it maxes out at 340mA, so the PHR was outputting 243mW at 340mA..lol i thinkt nhats the highest i've had a phr.
I'm not sure, we discussed that in the General section (Hallucynogenyc started the thread) but I got confused, drlava explained how the drivers actually work. http://laserpointerforums.com/f44/why-we-using-test-loads-linear-drivers-45610.html

I thought you were linearly (most likely logarithmically) increasing the current with a potentiometer. So how long do you leave the diode lasing at each current setting?

#### Mohrenberg

##### New member
not very long at all. just enough for the output to stop raising.

#### cappernicus

##### Member
Interesting...

The tester I built uses a lavadrive as its core, but it has a 1k pot, a 10k pot, and 2 or 3 10k resistors. It works like yours except with pots instead of switches, and my multimeter plugs into it in series with the laser diode for live power readings. It has three different ranges so I can easily and precisely power any diode from about 25mA to 1.2A.

i think diodes can withstand a LOT more current if they are slowly pushed up as opposed to being hit with tons of current
I can easily see how that would be the case. My question though is whether or not they can take higher power more easily after having been slowly led up to it.

Did the efficiency at lower power levels change after you did it?

#### Mohrenberg

##### New member
nope it stayed about the same...still outputting in the 80's

also, we need to regraph the sf-aw210. a few of them actually.

the one i built today did 178mW at 170mA with an acrylic lens.

#### nikokapo

##### 1
nope it stayed about the same...still outputting in the 80's

also, we need to regraph the sf-aw210. a few of them actually.

the one i built today did 178mW at 170mA with an acrylic lens.
I'll regraph it as long as you give me the data

#### canpower

##### New member
Hello,
PLEASE forgive me if this information is avaliable SOMEWHERE in this message board, I HAVE tried searching, including in this particular thread, but have not been able to provide the specific information I'm looking for, and given recent events in poting here, I DON'T want to piss anyone off by asking a question that people here may find to be stupid or obvious, so I'm just asking for a bit of patience and assistance, and not wanting to rub anyone the wrong way by sking for help. If it's right under my nose, and I've missed it, I apologize in advance for troubling anyone here.

What I'm wanting to know is how in "general" do I determine a laser diode pinout.

I recently purchased a few lots of diodes on ebay, and abroad, that do not come with specs, but they have markings on the diodes, some of which are pretty obscure, and I haven't seen them here in this thread.

I'll list a few below:

C-mount package:
T1498
434AC
920AC
T6002
V8328
754AC

Can mount:
JA191
HN758
HK364
HJ972
LU233
JY913
MT133
LD957 (OR 757)
T102
ND465
LR894
KB858
HC418
LT363
FH333

These are just a few numbers marked both in pen and also embedded into the diodes themselves, i cannot find anything in google regarding the numbers, so I'm wondering just how I can determine it's power, pinout and other specs before resorting to connecting one power polarity lead to one of the diode leads and then breifly "touching" the other diode lead with the other power supply source probe, I'm sure the 50-50 chance of getting the wrong polarity is not doing me any favours in screwing up the diodes that I am trying to use!

I don't know if there is a rule of thumb or not when determining pinout or voltages or even current ratings for that matter for laser diodes, I just don't want to unnessesarily FRY any of my diodes if I can avoid it, and of course would like to know ahead of time what the power output of adiode is so I don't waste my time trying to get a big output from a 5mw diode, thinking it might be a 1 watt diode or something!

I hope someone out there can steer me in the right direction!
Thanks!

#### nikokapo

##### 1
AFAIK there is no rule of thumb. At least not for the packages you've mentioned. The thing is that every electrical component has a different pinout (could be the same in some, but we can't know for sure). To get the data you asked for you should look up the datasheet for each diode (in Google), which are officially made by the manufacturer.

Don't be ashamed to post questions.

#### canpower

##### New member
Hi, thanks for your reply, I've tried looking up all of these in google, and there are SO many results, but none seem to actually "be" the results I'm looking for. I'm not sure if there is a dash, or a space, or something in these numbers, but I've tried everything, and none yeild any real results that tell me any useful info about the diodes, i have no idea who the manufacturer is, there is no manufacturer stamp on the diodes.

Should I just "assume" that 3 volts at 1 amp is good for a C-mount 1/2 watt 808nm laser diode with heavy heatsink, and peltier junction cooling? Is it possible to run these higher power diodes in CW mode without a peltier junction cooer, just air cooled?

Can you mount a c-mount diode on aluminum, or "must" it be a copper heatsink?