Best way to drive a LED with an NPN (for an LFO)

Started by drolo, April 08, 2014, 12:24:39 PM

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mth5044

Ah, I had read the past few posts and misunderstood. Damn that filter.

duck_arse

Quote from: drolo on April 09, 2014, 01:53:19 PM
Quote from: duck_arse on April 09, 2014, 12:00:03 PM
a PWM signal would be a square wave, no? in that case, led only goes on-off-on etc. not very linear.

You're right, I was so absorbed thinking about the resulting waveform and getting the led current to follow it that I forgot it was PWM...

So in this application, does one have to consider the average voltage the PWM creates or just treat the transistor as just a switch that is fed 5V impulses?
Sorry if this seems evident but I'm still trying to wrap my head around this PWM stuff ...

I'm only qualified to the "bozo" level, drolo, which is better in this case is beyond me.
You hold the small basket while I strain the gnat.