Hello AAC! This is my first post so don't hate on me if im not an expert on the rules and the formality of the group.
i would like to make a LED controller unit that has push button input using momentary switches but the ability to program each button independently as a momentary input or a continuous input. Thats the first part. second part is i need an easily programmable chip that can handle switching 3A on 20ch. I understand an Array of mosfets is more appropriate but im trying ton conserve space. Also if anyone has any ideas about a ready made mosfet switch board im all ears. My original idea was to have an adruino control a array of fets but it made complications in connections and reliability. last part im interested in is a type of switch i can use thats small and easy to switch using a low Vin to act as a gate but switch 5 ways. REF: Red Blue Green Amber White. if you have any other opinions im all years

Thank you by the way

 

I'm not with you on the last part about the switch but I think your best bet is to use an Arduino. If you're not confident in using MOSFETs then why not relay switches? There's no IC that'll allow you to pull 3A through it's outputs but the GPIO of an Arduino will happily drive a 5V relay. Unless your intent is to fade your LED's, in which case you'll definitely need MOSFETs.

 

I'm not with you on the last part about the switch but I think your best bet is to use an Arduino. If you're not confident in using MOSFETs then why not relay switches? There's no IC that'll allow you to pull 3A through it's outputs but the GPIO of an Arduino will happily drive a 5V relay. Unless your intent is to fade your LED's, in which case you'll definitely need MOSFETs.

i would like a dimmer function but not a pwm fade in fade out, only strobe and 50% brightness
ref:switch i want to be able to on command change to a different set of leds in different colours. without having there own independent fet or relay

 

strobe and 50% brightness

Whether you use an Arduino, NE555 or otherwise, it would be a PWM signal that affects the strobing of an LED (or LED's), a current limiting resistor on each LED will force it to work at half brightness. Why can't you use a MOFET? It's by far the best solution. If you want to switch a bunch of LED's very fast (strobe) then you'll have to use some sort of transistor.

 

Show us the LED arrangment, much follows from that.

 

as show in in the picture this is what im trying to strobe, (actual led arrangement is 4x4 parallel to series) but for every led will be 4 leds. one red, blue, green and white (amber with a mix of green and red) do you fallow?

i want to be able to switch each side to the colour of my choice without having ti flip though all the colours to find it.
thank you

 

I think I see what you're trying to achieve.

Arduino (or PIC) and 4 MOSFETS.

 

Looks like you are building a flasher for the top of a police car or ambulance.

I'd go Arduino and MOSFETs too, as to how many MOSFETs it depends on your lamp circuit diagram, do you have a spec/diagram for the lamps (even a part number would do)?

 

One does have to ask though, these look like official emergency vehicle flashers, are you allowed to have this on your car?

 

He's allowed to have them installed for display purpose (car show for example) but if he gets caught using them on the road, the law will cream him

 

here in canada as a volunteer firefighter you are aldwed to run green lights, as security on private property you may use red, and/or green and/or amber, if you are removing snow you MUST have blue flashing visible 360*. and amber and white is for anyone.
on private property you csn use any for display as long as you are not imoersonating a officer of the law.

i do security and volunter firefighting and snow removal, thus why i need to be able to change the colour.

this is only the front however i will need to have front (8 led heads) back (8 led heads) left and right side (2 each for 4 total) and 4 independent steady on work lights

my question is which would be better a pic or arduino, i dont know much about PIC's but i would like to learn, (i learn fast)

 

They are much the same except the learning curve is faster and there's a multitude of addon electronics readily available on the arduino

 

right where can i learn about the pic quickly? i want to make a PCB for my unit and not have to have a mounting option for the arduino, also going back to the ammount of fets, i would need one per unit right? I have been using the FQP30LN as my main project one but does anyone recomend anything better, and what kind of programing will i need to flash them as i want?

 

http://forum.allaboutcircuits.com/threads/a-goldmine-for-the-pic-programmer.44852/page-2#post-503555

http://www.picaxe.com/

 

Can you post a link to the led's you plan to use?

 

right where can i learn about the pic quickly? i want to make a PCB for my unit and not have to have a mounting option for the arduino, also going back to the ammount of fets, i would need one per unit right? I have been using the FQP30LN as my main project one but does anyone recomend anything better, and what kind of programing will i need to flash them as i want?

Here's what I would do;

Define the I/O e.g. How many inputs? how many outputs?
Choose a controller; any PIC or (other micro-controller) with enough I/O will do.

Define the I/O types e.g What are the input logic levels, how much current do the outputs need to switch etc?
Once you know these things you can design the peripheral hardware (you don't have to do this now).

Solve the logic. Once you have solved the problem the coding will be a lot easier. Flow charts are an ideal tool because they force you to analyse every step of the process and allow you to test and fix the logic before proceeding. and... the only hardware you require is a pencil and paper.

Build some hardware. You will need to test the code so build some hardware even if it is not the final design; it could just be a bit of stripboard with a socket for the micro-controller and some switches and LEDs to represent the I/O devices and run it from a battery.

Write the Code.There's no shortcut to learning to program a PIC but it's easier now because there is so much useful information available. Start with something simple such as lighting an LED when a button is pressed then make the LED flash, add more LEDs and make them flash in patterns etc......
Within a week or two you will know enough to write the code for this project. I'd recommend using assembly language, it's a bit fiddly but it's simple and will be relatively easy to derive from the flow chart you made earlier.

Test and debug the code on the hardware. This runs parallel to writing the code so rather than write all the code and then test it; break it down and test each section as you go.

Finalise the hardware. Now you know that your solution works.

 

okay i understand i worked with arduino for a while and I had a lot of fun with it got some good patterns but always hated trying to perfect the fets. how should thy be wired up? could i just wire the gate from the microcontroller the drain to the leds and the source from my power? or do i NEED a pull down resistor on the gate ? and or is there any pre made FETswitchboards or relay arrays? im trying to make this simple.

 

also im runnning this all off 12 V keep that in mind i will need a volatge dropping circut ... recomendations?

 

also im runnning this all off 12 V keep that in mind i will need a volatge dropping circut ... recomendations?

Again, a link to the led's you plan to use would be helpful.

 

Fv 3.5v
A 700ma