Driver confusion

I've got everything to start a build but I'm a little confused with this driver
Laser Driver Board V1 - 80-500mA, optional TTL - Detailed item view - OdicForce Lasers Online Shop

and this diode

Rohm High Power Red Laser Diode max. 240mW pulsed - Detailed item view - OdicForce Lasers Online Shop

I'm not sure if the diode has a -ve casing and how to wire this up. Does it need all 4 wires, bat +ve & -Ve to the driver +ve & -ve and LD+ve & -ve to the ld+ve & -ve on the driver and have the h'sink insulated from case ???

getting itchy fingers to finish this build

I am pretty sure that is the diode I got with my kit (case negative), but a different driver.

This driver is negative acting so if you use it with a diode that had a -ve case case pin it is important to ensure the diode housing is not connected to the power supply -ve or ground

Click to expand...

It looks like you will need either your batteries or diode insulated from casing.

So the way i will wire it is as I've stated, yes ?


*edit*

I hooked my driver to a test load (built by myself) tried to take a reading and got nothing, the batts did get a little warm tho (3 x AAA)

power is going thru the driver and can't see anything wrong with my test load, mabe the pot came turned all the way down ??? just gonna check

what reading did you take? did you try to measure current through the load, or voltage across it? you should have at least gotten some voltage at the output of the driver, even if there was no current through the test load

I got power from the output of the driver (Tested LD- and LD+) tested mA accross the resistor and got noting didnt try voltage accross the resistor tho. My build is all working now even tho I don't know what the output is

tested mA accross the resistor

Click to expand...

mA's are not tested with a parallel connection, it is likely that you have at some point burned the mA fuse in your meter.
You would not be the first to do so.

A working build with unknown current?
I hope you have either spare diodes or can accept lower than nominal output, cause you are unlikely to have hit the right current by chance.

I tested it on my test load first I thought that you tested the mA accross the resistor ??

Kookapeli said:

I tested it on my test load first I thought that you tested the mA accross the resistor ??

Click to expand...

Sorry, I must have misunderstood you.

Yes, you will be able to read mA over a 1 Ohm resistor directly as mV.
I was just imagining you turning the meter to mA and holding it across the resistor. (actually it might work reasonably reliably, you just use the meter as part of the load instead of the resistor)

I have just seen to many people mistaking parallel and series connection of a meter.

I don't know why I hadn't suggested this to you before Kook but you can get a pretty good driver, mA output reading by checking the current draw from the battery. These drivers don't need much power themselves... You can find out how much on the specs page you link to in your first post -

Laser Driver Board V1 - 80-500mA, optional TTL - Detailed item view - OdicForce Lasers Online Shop

(psst, it's 20-30mA! )

... Therefore, taking a reading by setting your DMM on the 5A, or 10A, setting; touching one probe on the threads at the tail cap; and one probe on the battery pack contact, (effectively making your DMM the clicky switch); you will get a pretty close approximation of the output. You just have to take the reading and subtract the 20-30mA, (for this driver but others may require more or less power). This is good and quick way to estimate the output of linear drivers. It also works with most green lasers too and allows you to know something about their personalities. (You will often see this data requested by those trying to help when questions are asked about faulty or damaged greenies).

It won't give any where near the same level of accuracy for a boost or buck driver setup but with experience it sometimes gives a clue at least and can be used to help diagnose problems that may exist.

M

Fantastic it's drawing .247A so I guess it's roughly 220-230mA which the output should be (according to odicforce) around 200mW I could get more out of it as the pot is just over 1/2 way, It was this one Laser Driver Board V3 - 0-300mA - Detailed item view - OdicForce Lasers Online Shop I used in the end. Is running a Rohm at around 200mW a bad idea ??? what is the max it can run at ?

Well, if it's this diode -

Rohm High Power Red Laser Diode max. 240mW pulsed - Detailed item view - OdicForce Lasers Online Shop

then the 247mA should be fine. As a rule of thumb, we tend to hit the pulsed rating as a CW rating so the 240mA pulsed manufacturers rating falls neatly into the range. I'd say you wil be fine at that current but you will likely only be getting about 100mW optical output which would tally with what you've said already about outdoing your 100mW green. Your next step will likely be up to the LPC-815 diode, or LOC, for more power!

The setup you have there should be absolutely fine and I would leave it as is. Your next build will no doubt be of higher power so just wait until then rather than blowing this diode and having to replace it.

Good measuring! Now you know roughly what your laser is outputting without an LPM, (although this is clearly a very rough guestimate!)

M

Cool , havnt got a blue/violet yet so my next build will more than likely be a 405nm or a 445nm, will have start saving