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ArcticMyst Security by Avery

Did I blow my M140 diode?

Joined
Jan 8, 2008
Messages
9
Points
0
While do some tests with an M140 I'm configuring for a laser cutter CNC rig, I think I might have fried the diode.

I'm using constant current ttl driver like this one:
http://1.bp.blogspot.com/-1CXU52VYHtY/VNFO4rgDjwI/AAAAAAAABFY/tmR5MUjyMSk/s1600/575720011537.png

As I ramp up the signal on the TTL line, I notice the diode becoming brighter, but around 400-500 mA, it goes dim, though it continues to draw current all the way up to the max I have it set at (1.5A).

I'm guessing I accidentally fried the diode with a lose connection, or while connecting the diode to the board, as I hadn't soldered down the lines yet.

I've ordered a new one, but I assume my conclusions are correct?
 





diachi

0
Joined
Feb 22, 2008
Messages
9,700
Points
113
While do some tests with an M140 I'm configuring for a laser cutter CNC rig, I think I might have fried the diode.

I'm using constant current ttl driver like this one:
http://1.bp.blogspot.com/-1CXU52VYHtY/VNFO4rgDjwI/AAAAAAAABFY/tmR5MUjyMSk/s1600/575720011537.png

As I ramp up the signal on the TTL line, I notice the diode becoming brighter, but around 400-500 mA, it goes dim, though it continues to draw current all the way up to the max I have it set at (1.5A).

I'm guessing I accidentally fried the diode with a lose connection, or while connecting the diode to the board, as I hadn't soldered down the lines yet.

I've ordered a new one, but I assume my conclusions are correct?

Sounds like a terrible quality driver for starters ... TTL should be either on or off, it shouldn't get brighter as you up the current. Where did you measure current draw?
 
Joined
Jan 8, 2008
Messages
9
Points
0
To clarify, I wasn't increasing the current on the TTL side. I was changing the PWM signal on the TTL side from 0 to 100%, and measuring the current going through the diode.
 
Joined
Sep 20, 2008
Messages
17,622
Points
113
While do some tests with an M140 I'm configuring for a laser cutter CNC rig, I think I might have fried the diode.

I'm using constant current ttl driver like this one:
http://1.bp.blogspot.com/-1CXU52VYHtY/VNFO4rgDjwI/AAAAAAAABFY/tmR5MUjyMSk/s1600/575720011537.png

As I ramp up the signal on the TTL line, I notice the diode becoming brighter, but around 400-500 mA, it goes dim, though it continues to draw current all the way up to the max I have it set at (1.5A).

I'm guessing I accidentally fried the diode with a lose connection, or while connecting the diode to the board, as I hadn't soldered down the lines yet.

I've ordered a new one, but I assume my conclusions are correct?

Yeah... it looks like you LEDed the Laser Diode and you even stated
why it happened. Time to get another one. Been there... Done that.

Jerry
 




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