My needs are very simple, and I could definitely use some project guidance.
I need to drive about 6-8 IR Leds arranged separately around an object, always on, no connection to the IR receiver system part (which is up and running and working fine).
What should be my angle on this? I have experience with parallax many years ago, but I don't feel much like dealing with bread boarding their PICs (unless something has changed). I am trending towards arduino anyway as I am already using their breakout board for camera app, and I am wondering whether I should use the Arduino to drive my IR transmitter setup? Sorry for the disjointedness of the question, but its as if there are too many options.
Perhaps you should explain what the IR transmitter needs to do before you decide how to drive it?
What protocol? Number of keys? Desired size? Led power? I can keep going with the questions but hopefully you can see my point - how can anyone help without knowing what you actually want to achieve?
Well, I guess I left myself open on that one. The IR transmitter will serve as a beacon/illuminator with a field of illumination to be determined and voltage unknown as well. I need an experimental setup to measure these things to determine the correct configuration that best fits the needs of the receiving camera. It would be satisfactory to detect the IR Led at distances 3-6 feet., but this too will be experimental. I have been looking into the "dome" IR Led that negates the conical shape of a "normal" LED being detected. Therefore I have been looking for a really small breadboard - i mean really small - so I can swap out resistors/Mosfets with candidate LEDs, much like Railroder described. I want a solderless solution with 6 -8 sensors but I don't want to solder and test and upteen configurations. Surely, there is nothing new under the sun, but I can't seem to find an ready-made solution.
So basically I need a circuit in which I with parts I can substitute in and out. Breadboard-ish.
Quick question about serial LEDs/resistors. If I apply V/R(in ohms) to every LED in serial, I get I (current) for each set. In working up my power supply for breadboard do I add all of the I's together as a total I output necessary assuming my voltage is adequate after the drops across the LEDs.?
In other words how do I work up the voltage and current of my breadboard PSU for serial LEDs. Thx
Also what simulator software is everybody using these days for basic electronics?
I've been reviewing power choices for my multi-LED daisy-chain project. It seems there are many solutions built for this in LED Drivers, constant current versus voltage, etc. My hold up is how do I power my LED Driver? They invariably have +/- outputs but also +/- sources to what I am assuming is source. But what is the source? I have yet to find an LED Driver that has a wall adapter. What am I missing? Should I breadboard power and use that for the LED Driver hot/grnd?
clangray:
I've been reviewing power choices for my multi-LED daisy-chain project. It seems there are many solutions built for this in LED Drivers, constant current versus voltage, etc. My hold up is how do I power my LED Driver? They invariably have +/- outputs but also +/- sources to what I am assuming is source. But what is the source? I have yet to find an LED Driver that has a wall adapter. What am I missing? Should I breadboard power and use that for the LED Driver hot/grnd?
What you're missing is a whole LOT of basic how-to and what-for that you seem to think of as trivial.
If a device sources power, it is supplying current. The device could be a battery, power supply, chip, transistor, etc, as long as current flows from/through it.
The opposite of source is sink. Sink drains current.
But do you know basic electricity? Electrons, conductors, voltage, Ohm's Law?
How to power a led driver depends on the led driver. The all have datasheets, start there.
The fancy led drivers blink the leds faster than eyes can see to do it, that's PWM for brightness control. Will your camera be faster than human eyes?
The fancy led drivers blink the leds faster than eyes can see to do it, that's PWM for brightness control. Will your camera be faster than human eyes?
This is true for LED Drivers? The camera clocks 63fps in infrared detection configuration, but many things could change that, not to mention a blinky LED -- even unseen by the human eye.
That's a real problem. Thank you for bringing that up.
This is due to how high efficiency transistors (like MOSFETs) are only efficient when full ON or full OFF, they get hot when halfway so the answer is pulse width modification to change how long the ON and OFF phases of the blink are.
You can make an always-on led brighter or dimmer by changing the resistor, at least up to when the led degrades from too much heat which is what you did have a plan to do. Why not use 5V and a 220 ohm resistor and see how far away you can detect it?
Sometime point your camera at a lit red led and see what color shows.
Well, I guess I left myself open on that one. The IR transmitter will serve as a beacon/illuminator with a field of illumination to be determined and voltage unknown as well. I need an experimental setup to measure these things to determine the correct configuration that best fits the needs of the receiving camera. It would be satisfactory to detect the IR Led at distances 3-6 feet., but this too will be experimental. I have been looking into the "dome" IR Led that negates the conical shape of a "normal" LED being detected. Therefore I have been looking for a really small breadboard - i mean really small - so I can swap out resistors/Mosfets with candidate LEDs, much like Railroder described. I want a solderless solution with 6 -8 sensors but I don't want to solder and test and upteen configurations. Surely, there is nothing new under the sun, but I can't seem to find an ready-made solution.