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    @Maddus Mattus:

    Agree with what you said, other than LED forward voltages are typically closer to 2V - 3V, much higher than the forward voltage of regular diodes.

    I also have a BS in electronics and used to be heavily into all sorts of electronic circuits. I've since switched to software development but my dream job is one that combines electronics with software. Unfortunately every time I look into those kinds of jobs, I find them to be few and far between, and they don't seem to pay anywhere near what a software development job pays.

    Actually I used to love analog electronics, and designed and built all sorts of weird and wonderful things. I had a ZX Spectrum 48 and designed and built an 8-bit successive approximation ADC out of resistors and transistors, no ICs. It basically uses a series of transistors biased to turn on/off based on a threshold voltage, and subtract half the voltage if "on" and passes the remaining voltage to the next stage.

    Another project was designing and building a class-D amplifier (this was long before they became somewhat common). This is basically a powerful binary switching amplifier that can only be in one of 2 states: High or Low voltage (+50V or -50V). Then using pulse width modulation at a high switching frequency (250KHz in my case), and passing the square wave through a lowpass filter, you can get an analog signal out that can power a speaker. The beauty is that since the output transistors (mosfets) are either fully on (0V across them) or fully off (0 current through them), the theoretical power loss is 0 Watts (since power is volts x current). This means you can have a very powerful amplifier using no or very small heatsinks, and have it be very compact.

    My 1st microcontroller project was an 8051 driving a bunch of large 7 segment LEDs allowing you to feed MIDI into it where it would show you the song position in realtime. The idea was to mount it somewhere in a recording studio and then everyone can see exactly where in the song the current recording was at.

    Ah, those were the days...