Magic Matt
Enlightened
Ok, here's what I want to build....
A microprocessor (PIC) controlled LED light with a little LCD display showing you the power output, battery levels etc. complete with controlls to brighten and dim the light. I want to drive a P7 LED.
What I already think I know how to do...
Things I am vague on ...
What I have no idea how to do, and nead to learn...
What I'm looking for is links to the knowledge, or the right words to search for so I can find the information which is probably somewher on the forum.
I have a variety of donor chassis, including a really bad 2-D maglite copy (cheap $5 incan from a supermarket) a 3-AA multi-5mm LED thing, and a variety of hand-held boxes. I'm also under no illusions that as this is my first build, it probably wont be very efficient or portable, but I am more looking to get the thing working as a learning curve, then worry about how to reduce the size.
I do, however, have a lot of enthusiasm for this at the moment - far more than I thought I would have!
lovecpf
A microprocessor (PIC) controlled LED light with a little LCD display showing you the power output, battery levels etc. complete with controlls to brighten and dim the light. I want to drive a P7 LED.
What I already think I know how to do...
- Program the PIC to
- accept input from buttons (debounced)
- control an LCD display and illuminate it on demand
- provide PWM output on various pins of the PIC
- read analogue voltage in via the PIC and analyse it
- Build the regulated electronics to drive the PIC and LCD from a 6VDC+ power source
- Control solid state relays to turn things on and off
Things I am vague on ...
- I think I need to drive the P7 at 3.6V 2800mA for full brightness. If an NiMH AA battery can deliver 1.2V @ 600mA then I'd only need 4 of them, but I think it would be better to have more... like 8 or so.
- I need a heat sink, but I don't know how to work out how big it needs to be.
- Whether I should buy the bare emitter, or the emitter mounted on a star.
What I have no idea how to do, and nead to learn...
- Drive a P7 (I've driven 5mm LEDs, but nothing like this beast) - I believe I need a current driver not a voltage driver.
- What circuitry I need to use PWM to control the brightness of the LED. I realise I need a driver, and there are thinks called Sharks (not the ones on Blue Planet) but that's as far as I've got.
What I'm looking for is links to the knowledge, or the right words to search for so I can find the information which is probably somewher on the forum.
I have a variety of donor chassis, including a really bad 2-D maglite copy (cheap $5 incan from a supermarket) a 3-AA multi-5mm LED thing, and a variety of hand-held boxes. I'm also under no illusions that as this is my first build, it probably wont be very efficient or portable, but I am more looking to get the thing working as a learning curve, then worry about how to reduce the size.
I do, however, have a lot of enthusiasm for this at the moment - far more than I thought I would have!
lovecpf
