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FrozenGate by Avery

Suutable driver for LPC-840

I've used a amc7135 driver for my ML101U29 diode in my signature. As long as 350mA or 370mA is OK for you.
Just be careful as the amc7135 has a max input voltage of 5.5V IIRC so two Li-ion's will kill it.
 
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That's all any laser diode driver does. It regulates the current, not the voltage.
 
Power supplies are called constant current and constant voltage controlled. Drivers are just drivers. They are supposed to be current controlled, but you often run up on Chinese drivers that are only voltage controlled. Caveat Emptor.
 
TinLethax said:
Can I use this ?
https://m.aliexpress.com/item/32806...32806189975&shortkey=RZfMzqiu&addresstype=600

The AMC7135 @350mA driver
Click to expand...

Yes, there is a very good reason not to use this as your driver. They were made to drive LEDs and because LEDs are more forgiving of spikes and shifts in current they don't bother to filter them out. That is why these drivers are so cheap. I tried using them once many years ago and the failure of them kept me from ever making that mistake again.
 
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paul1598419 said:
That's all any laser diode driver does. It regulates the current, not the voltage.
Click to expand...


Not to challenge you here man but my studies of circuits and drivers says they control both? Or else you'd have bad voltages also flowing through the LD not just amps?
 
TinLethax said:
Oh .So what about LM317?
Click to expand...


LM is linear and regulates voltage via feedback loop, well too, but you MUST add a thermal runaway protection and amp/voltage limiting/breaker resistors/relays which ever way ya wanna go with it. The reason for this is the internal resistance of the LD varies under heat and the feedback loop will keep adding voltage and current to try to maintain that steady reference voltage. So no thermal protections = whats known as thermal run-a-away.
 
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KrombopulosRik said:
Not to challenge you here man but my studies of circuits and drivers says they control both? Or else you'd have bad voltages also flowing through the LD not just amps?
Click to expand...

KrombopulosRik said:
LM is linear and regulates voltage via feedback loop, well too, but you MUST add a thermal runaway protection and amp/voltage limiting/breaker resistors/relays which ever way ya wanna go with it. The reason for this is the internal resistance of the LD varies under heat and the feedback loop will keep adding voltage and current to try to maintain that steady reference voltage. So no thermal protections = whats known as thermal run-a-away.
Click to expand...

Double posting on the Forum in a short period
of time is frowned upon by the community...

It is easy to Combine and Edit your Posts by
using the [EDIT] button at the bottom right
of each of your Posts.


Jerry
 
KrombopulosRik said:
Not to challenge you here man but my studies of circuits and drivers says they control both? Or else you'd have bad voltages also flowing through the LD not just amps?
Click to expand...

If you are talking about filtering out spikes and transients, that is only a side issue and not a control of voltage like one would see in a voltage regulator. If you are using a red diode you should know the the forward voltage is going to be low and therefore you wouldn't use a boost driver on that diode. If you are using a 490nm diode, you should know the forward voltage is quite high and you would want a boost driver. But, in the end, they are all just current regulators and nothing more. You can add a TTL input for PWM control of the output or and analog control that will vary the current between two set points, but it is still just a current regulator.
 
KrombopulosRik said:
Not to challenge you here man but my studies of circuits and drivers says they control both?
Click to expand...

"Not to challenge you, but here's a challenge"
Well, not to say you're wrong, but you're wrong.

You need only to look at a sample IV curve of a diode to see why:

Current-voltage-I-V-curve-of-a-silicon-p-n-junction-diode-43.png


Minor thermal effects aside, the diode can ONLY operate along this curve. For example, it is possible to apply 0.9V to a diode, and it is possible to send 5mA through a diode, but you CANNOT do both at once.
 
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