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LED chaser circuit

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ferrariracers1

New Member
Hello everybody! I hope you all are doing fine!!..
Coming to my problem......I have heard about a 10 led chaser circuit using the 555 timer, 4017b decade counter.....But in Chandernagore, in India, there are professionals who build circuits so as to light up large LED chasing patterns....I just got a glimpse of the circuit and i found out that the following components were present:
1. 555 timer ic
2. 2 capacitors
3. set of resistors with the timer
4. 4017 decade counter ic
5. BC 547 transistors
6. Zener diodes with each transistor(BC547). I dont know the rating.
7. Two resistors after each transistor (green in colour).
8. 2N6107 PNP transistors after each BC547 transistor..
On asking about the working about the circuit the local shopkeeper said that the output comes out from the collector portion of the 2n6107 transistor and that it is a simple led chaser circuit.

I want to build this circuit on my own.....So i need your help to finish this circuit.....I would be highly obliged if anybody of you can give me the exact circuit diagram with these components......
 

ferrariracers1

New Member
Thank u so much for the reply but i went throught this topic but could not find the suitable circuit......I would be very thankful if u could give me the exact circuit!!!
 

ericgibbs

Well-Known Member
Most Helpful Member
Thank u so much for the reply but i went throught this topic but could not find the suitable circuit......I would be very thankful if u could give me the exact circuit!!!
hi,
This is the most simple version.
Fun with LEDs
 

ferrariracers1

New Member
I have gone through all these circuits but i cant just implement that how can we feed the output og BC547 transistor to the 2n6107 transistor to use it as a switch.
 

ericgibbs

Well-Known Member
Most Helpful Member
I have gone through all these circuits but i cant just implement that how can we feed the output og BC547 transistor to the 2n6107 transistor to use it as a switch.
hi,
If you want the exact same circuit that you saw working, its necessary to have their circuit diagram.
 

ferrariracers1

New Member
ok...I will try to have a pic of it and give it over here.....I think then you will hjave a guess of what is the actual circuit!
 

ericgibbs

Well-Known Member
Most Helpful Member
ok...I will try to have a pic of it and give it over here.....I think then you will hjave a guess of what is the actual circuit!
Thats sounds the best idea, we can look it over, post it when you can.
 

dg2829

New Member
Actually I'm looking at a similar sort of thing, I have the circuit to do the chasing but I want to use some very high power led devices with the circuit The high power LED's provide over 1000 Lumens light output.

How do I do this the supply power for the whole thing will be 12V car battery (My 4x4)
The LED devices use between 10V-12V DC power is 1000ma to 1500ma per LED device directly. I want to use 2 High power LEDs per output from the led chaser CCT. I really want to be able to put 2 outputs per pair of LEDs driven (that would should give a double flash)

Anyway I figured the foundation would the typical led chaser circuit with your typical low power LEDs in it and then drive FET or 2 per 2 outputs (double flash) flash would be variable as that is controlled by the led chaser circuit. each channel really needs to go hard on and hard off per channel.

I would like to be able to turn on a FET or FETs or Transistors or similar with the output from each low power output that normally drives the low power leds or more to the point 2 of the outputs (double flash) for these high power LEDS, the amount of current per output could be as high as 5000ma. I figure a 10 channel led chaser circuit would be able to say drive 5 channels x 2 high power leds per channel to get the my desired result.

I thought adding a simple addon circuit would be the way to go that way it is expandable as might be needed.

I am unfortunately no good at designing this stuff but I I can build it that I can do

Could anyone offer or provide the extra circuit/s that would make this add-on work with the traditional led chaser circuit please.

Thanks advance all.
 
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Reloadron

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You pretty much called it right. A basic chaser circuit, however, let the chip outputs drive mosfets (Logic Level MOSFETS would be a good choice) and the MOSFETS drive the loads. A simple chaser with 0 through 9 what you are looking for for starters?

Ron
 

dg2829

New Member
The chaser circuits are easy, there is a myriad of them out there in the world including complete little kits for about $7.00 including the parts, just solder together and done, so that's not the problem. How much power does one of those little Red or Green LEDs use (Not Much), but that output then needs to drive the secondary circuit/s.

It's the extra CCT/s I'm after, which bits to use and the CCT diagram so I can put it together, I can describe what I want, I can't design it, but I can build it.

It's the CCT and the part numbers needed to build it please, I have been looking at other circuits on the WWW maybe a IRFZ44 FET maybe (don't know if it is logic level FET or not) there are a couple of other circuits that use this as a high power switch, still need the circuit and the values of the bits required please.

Help please thanks in advance.
 
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Reloadron

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OK, the first attached circuit is a basic LED chaser circuit, VCC is not shown but for an automotive application I would run it off a 5 volt regulator like a LM7805. The use of the 7805 for an automotive app can be argued but it will work with some good filtering or a better regulator could be used. The effect of this circuit is seen in the second image.

Now for what you want the LEDs as drawn would be eliminated. They would be replaced with logic level mosfets from this family and the MOSFET you linked to is not a logic level and requires a higher gate voltage. You would need ten of them to drive your higher loads which would be powered off the 12 plus volt automotive power directly. Minor issue is that automotive can range between 12 and 14 plus volts.

If something like this is what you want maybe tomorrow I can get it drawn up or over the weekend.

Ron
 

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dg2829

New Member
Yes that looks like what I'm after (Chaser Circuit), just one thing to get the double flash is it better for two outputs from the IC or use 2 FET outputs to the High power LED's.

The high power LED's use 10V - 15V and upto 2000ma typical light out put around 1000+ lumens, there will be 2 maybe 3 in parallel per channel (5 Channels) and they will double flash. I'm not sure how close I want the flashes so that will take a bit of fiddling as to which outputs are used for the double flash.

Oh forgot the Logic level FETS yes I see, said the blind man, the others when I went back and looked hard are power FET's.
I'm new to this but I learn although slowly :(

The power for the Chaser CCT I figured some sort of regulator would be needed the power from the car is just too high in most cases.

Thanks
 
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Reloadron

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I am not sure what you have in mind with this "double flash" term?

The way the thing works is the 555 timer is functioning as a clock. For each positive going clock pulse the 4017 counter advances one count up. Placing a few in parallel won't be a problem as the MOSFETs will handle the current. Do you have a part number or link to these LED assemblies?

Ron



Ron
 

dg2829

New Member
Rather than connecting one output use two different outputs say 1 & 3 from the LED chaser circuit to one input of the FET so that the high power LEDs flash twice with a longish pause before those particular ones flash again thats all.
Obviously there are other ways of doing it but this is about the most robust way I know of that is also scalable as well and no programming at all.

Um No part number for the LEDS I have attached a picture of one though

And the specs for this particular one are

Color : White
min 800 lm, max 1000 lm
100 to 110 deg angle
Forward Voltage 10.0 to 12.0 VDC
Forward Current 800 ma to 1000 ma
and they do need a heat sink but that's OK for my use.
 

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Reloadron

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Most Helpful Member
Got it.

Ron
 

Reloadron

Well-Known Member
Most Helpful Member
I would use this mosfet or any mosfet like it. I placed 10 Ohm 10 Watt resistors in series with each LED simply for current limiting reasons and since you plan to parallel several. I only show two pairs.

The circuit is a cut away version of the circuit I posted earlier. I would run the basic circuit off 9 volts. You can use a LM7809 regulator to get 9 volts from the 12 volt system real easily. I would filter the in and out of the 7809 with a .1 uF and 1000 uF cap on each side.

Anyway, I believe the attached is about what you are after.

Ron
 

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