Other Ways To Control Led's Other Than Pwm


Hello all, Im wiring up the XLR-ONE Mini and started with the 12 x led light bars i made for the front and rear of the robot. when i plug them directly to a 3v power source they light up real bright but when i plug them into the v4 and use pwm, they are not bright at all. Whats a good way to be able to control the lights(on-off) thru the v4 but with full brightness?


Other than using a TIP122 transistor switching circuit and a voltage regulator (that was suggested to me a while back but haven't tried it yet), I use Brick Relays that can switch up to 2 amps which is real simple to connect and works really well using SetDigital(On) and (Off) commands. Simple, cheap and effective. Hope that helps.


@Steve G the Led strip takes only 3.2v the bricks use 5v.


I know. You use a 5v regulator with the relay and whatever power you need for the LED's. That's what I'm using now to turn on and off a set of 3.5v LED's (or 3.2v in your case).


@steve g ok so basically powering the led' s off the v4. ok so how did you wire the brick to the led to the v4?


I connected a 5v reg to the 2.54mm pins seen below...

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then regulator + and - and signal wire in to a digital port. I actually have my LEDs running off a drop down buck converter running off the V4, as I have a string of 20 bulbs to light. I just broke in to one of the LED cables and run them through the blue "NC", Normally Closed terminals on the relay.



Quick question.

You say you have the 12x LED bars connected to the V4. How exactly? I assume you're running them off a 3.3v signal pin as you mention using PWM. If this is the case then amperage could be a real issue. If you have them running of a 3v regulator or similar from an external power source, then they way I mentioned I do it in the above post will work for you just fine.


Without the schematic/wiring diagram or a detailed explanation of how exactly the LED bars are connected it's difficult to answer your question.

With anything, including single LEDs (however not required for single LEDs) I use the TIP switching circuits to ensure enough current and correct voltage are applied to the LED circuits.

Basic electronics will teach you about resistors which should be used with all LEDs. There are many online calculators which will tell you the correct resistor to use in series with an LED or LED array if you are unable to calculate it yourself. Google will bring up a selection of good calculators. These will also answer your question about powering an LED or LED array that requires a voltage of 3v3 with a 5v supply.

There are also hundreds of great sites out there which will cover basic electronics to advanced electronics should you wish to learn and understand everything you are designing and selling. Google is your best friend for that, just search for "basic DC electronics" or "DC electronics for beginners" and you'll get a good list of resources.


@rich the led's are soldered parallel. all pos to pos and all neg to neg.


I use steve G's method with brick relays and haven't looked back since