The problem of lm 338

[trinh hong phuoc]

I have some lm338 and i want to build 1w driver for 500mw-p73 mis

I want to ask is that the driver build process is like lm 317 right?

What is the life of the diode 1000 hours or 100 hours? ------- Please help me !!

 

[diachi]

I have some lm338 and i want to build 1w driver for 500mw-p73 mis

I want to ask is that the driver build process is like lm 317 right?

What is the life of the diode 1000 hours or 100 hours? ------- Please help me !!

Yes... same as the LM317 - look at the datasheet...

Life of the diode depends on what current you run it at and how hot it's getting mostly. Hard for us to predict accurately.

 

[lasersbee]

Not to mention... every LD has different specs
and requirements...

If you run a small 5mW red Laser diode at 20ma it
will easily last over 1000 hours if not more. If you
run that same LD at 200mA it will last less than a
day.

Jerry

 

[paul1598419]

If you are going to use that linear driver to drive the ML501P73 diode at 500 mW or greater, the waste heat from the driver will be something you'll have to take into account. It will most likely be too large to put into a pointer also. For these red high power diodes I use a buck driver, which doesn't need to be heat sinked to run for a couple of minutes.

 

[diachi]

If you are going to use that linear driver to drive the ML501P73 diode at 500 mW or greater, the waste heat from the driver will be something you'll have to take into account. It will most likely be too large to put into a pointer also. For these red high power diodes I use a buck driver, which doesn't need to be heat sinked to run for a couple of minutes.

Yeah, going to need a heatsink on that LM338 for sure.

 

[trinh hong phuoc]

Yes... same as the LM317 - look at the datasheet...

Life of the diode depends on what current you run it at and how hot it's getting mostly. Hard for us to predict accurately.

Can I use it to build a 500mw mis at 900ma?

I've got plenty of capacitors and resistors attached - and what I worry about is heat when it works

Please help me with

If you are going to use that linear driver to drive the ML501P73 diode at 500 mW or greater, the waste heat from the driver will be something you'll have to take into account. It will most likely be too large to put into a pointer also. For these red high power diodes I use a buck driver, which doesn't need to be heat sinked to run for a couple of minutes.

You use amc 7135

Not to mention... every LD has different specs
and requirements...

If you run a small 5mW red Laser diode at 20ma it
will easily last over 1000 hours if not more. If you
run that same LD at 200mA it will last less than a
day.

Jerry

I will run a 500mw mis at 900ma with a Lm 338 driver with capacitors-can you predict their lifespan based on the experience you have?
thank you so much

 

[lasersbee]

You are not new on the Forum anymore.
You have been amicably advised of Double
and Triple posting etiquette on the Forum
and once again we see tripple posts.....:tsk:

http://laserpointerforums.com/f40/new-experiment-green-laser-100909-2.html#post1485449

You can easily combine posts by using
the [EDIT] button at the bottom right of
any of your posts.
Double posting is considered bad Forum
etiquette and is frowned upon...:beer:


Jerry

 

[trinh hong phuoc]

iam sorry