Old 08-16-2016, 03:26 AM #17
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Default Re: Laser with throttle capabilities

You'd also want to put the pass transistor on the other side of the laser diode. It would work as-is if you had 12V input maybe, but it's best practice to put NPNs on the "low side" when possible.


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Old 08-16-2016, 05:25 PM #18
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Default Re: Laser with throttle capabilities

Quote:
Originally Posted by Cyparagon View Post
You'd also want to put the pass transistor on the other side of the laser diode. It would work as-is if you had 12V input maybe, but it's best practice to put NPNs on the "low side" when possible.
Cool, I noticed a few schematics on-line my way buy most were the other way. I guess coming from a software engineering background I think "vary the high side and hold the ground 'constant'". But in reality it doesn't matter whether the high or low side if the LD is changed.
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Old 08-17-2016, 04:22 PM #19
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Default Re: Laser with throttle capabilities

You can have high-side regulation instead, but a PNP/P-MOS is better suited.
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