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running lights

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electro007

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Hi,

I'm building a running lights controlled by a TTL. How i can drive the bulbs so they can be fully light for a very short time each one?
I would like to use a minimum 10w/12v bulb.


Thanks in advanced for any help.
Louay
 
running light

I do not think you can use TTL's to drive a 12V bulb as the maximum Vout for a TTL is specified at 5v.
Can you please clarify your post? What exacly is a running light?
 
second thoughts

If i get your message right, I think your circuit would need a MUX(so as to
make a selection between the various bulbs). If you're using 3 bulbs, for example, you'll need a 3-to-1 line MUX. You'll also need a kind of delay circuit which would trigger a relay driver.

That should realise your circuit. I may be wrong though and I hope subsequent post would clarify if more. :D
 
If you're asking how to drive the bulbs directly from TTL then perhaps a circuit like this would work, though the IRL510 is "overkill" for your 12v 1a load...

Regards, Mike
 

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is TTL essential in your circuit.
u could use a simple counter and a give the o/p to a decoder which would drive relays.
 
Running Lights?
Do you mean you want lights to chase around, one after the other?

Incandescent light bulbs waste a lot of power by making heat. Because they must get hot to produce light, they need a certain amount of time to heat-up so you can't blink each one for a very short time.

LEDs can make light instantly and are very efficient. Try my "6V Ultra-bright LED Chaser" project:
https://www.electronics-lab.com/projects/games/004/index.html
The LEDs light for only 15ms each and chase around in a circle for a few times around, then pause. It uses modern 74HC Cmos ICs that still work fine when the 6V battery has discharged to 4V. Since the LEDs are only briefly lighted and Cmos uses almost no current then the battery lasts for a very long time. The project has a chasing speed control and uses pulse-width-modulation for its brightness control. :lol:
 

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Have you ever thought of using a circuit based on a pic? maybe using a pic16f84a. You can even program the time you want each led on and off using a program called pic simulator ide and then burn it into the chip using a programmer and WinPicProg (for example).

i've done a similar circuit and you can bypass the leds with a resistor and then connect it to the chip. it doesn't require much hardware. just the oscilator and maybe a 7805 to regulate the power. very likely you can find that on the net.
 
not exactly the solutions that i needed

Hi Guys,

Thank you all about your ideas for solving my problem, but what i mean in my question, what is the circuit in the final stage that i can use to light a 20w/12v halogen bulb, for a short time?
Probably i need transistors that can drive the bulb, and the question is, how doeas the circuit looks like?

Thanks.
Louay
 
How short is the time to light the bulb?
It uses more power than a car's turn signal so will be slower. A lightbulb turnsignal doesn't flash on and off, it ramps its brightness up and down rather slowly about 1/2 second ramping up and another 1/2 second ramping down. If you power it for a time that is too short then it won't fully lightup.
 
Re: not exactly the solutions that i needed

electro007 said:
Hi Guys,

Thank you all about your ideas for solving my problem, but what i mean in my question, what is the circuit in the final stage that i can use to light a 20w/12v halogen bulb, for a short time?
Probably i need transistors that can drive the bulb, and the question is, how doeas the circuit looks like?

Thanks.
Louay

Mike, K8LH gave you a circuit to drive the lamps in his post above.

Len
 
Re: not exactly the solutions that i needed

Hi,

Yes i know how to drive a bulb from TTL, but what i'm looking for is how to light the bulb in full brightness for a short time?
And because i'm using a halogen bulb, the time for lighting up is very long, that is why i don't get it full light.
Is there any way to solve this?

P.S. I'm building the knight rider scanner. I know there are a lot of sites, but no one is telling how to do that, or if it realy worked for somebody.

Regards,
Louay.

ljcox said:
electro007 said:
Hi Guys,

Thank you all about your ideas for solving my problem, but what i mean in my question, what is the circuit in the final stage that i can use to light a 20w/12v halogen bulb, for a short time?
Probably i need transistors that can drive the bulb, and the question is, how doeas the circuit looks like?

Thanks.
Louay

Mike, K8LH gave you a circuit to drive the lamps in his post above.

Len
 
If you want the bulbs to flash like strobe-lights, then use strobe-lights!

Since a 20W incandescent bulb takes time to heat its heavy filament up to a light-emitting temperature, how about giving it a blast of current to get the electrons moving faster. I bet if you give a 12V bulb a blast of current from about 18V it would lightup pretty fast (and won't last very long).

Of course the current would be much higher than normal at 18V, and a lightbulb's filament draws about 10 times its normal current when cold anyway. So you might need to supply current pulses of 50A(!) from some kind of an inverter.
Maybe the Knightrider car in the TV show used 6V bulbs operating with 12V pulses of current to do what you want. :lol:
 
The new 5W Luxion LEDs would do what you want, if you can afford them.
 
Re: not exactly the solutions that i needed

electro007 said:
Yes i know how to drive a bulb from TTL, but what i'm looking for is how to light the bulb in full brightness for a short time?
And because i'm using a halogen bulb, the time for lighting up is very long, that is why i don't get it full light.
Is there any way to solve this?

I don't think so?, it's a characteristic of the halogen lamps.

You might try 'preheating' them though?, by having them permanently fed through resistors, with too low a current to make them visibly light up - possibly this would speed up their lighting up time?. I can't say I've ever heard of it being done, but it's perhaps worth investigating?.
 
Re: not exactly the solutions that i needed

I would like to tell you that your idea of preheating was somewhere on the internet, someone already suggested that, but i didn't succeed to get a good circuit from someone that tried it.
Maybe i'll try it by myself.

Thanks a lot.
Louay

Nigel Goodwin said:
electro007 said:
Yes i know how to drive a bulb from TTL, but what i'm looking for is how to light the bulb in full brightness for a short time?
And because i'm using a halogen bulb, the time for lighting up is very long, that is why i don't get it full light.
Is there any way to solve this?

I don't think so?, it's a characteristic of the halogen lamps.

You might try 'preheating' them though?, by having them permanently fed through resistors, with too low a current to make them visibly light up - possibly this would speed up their lighting up time?. I can't say I've ever heard of it being done, but it's perhaps worth investigating?.
 
Re: not exactly the solutions that i needed

Nigel Goodwin said:
electro007 said:
You might try 'preheating' them though?, by having them permanently fed through resistors, with too low a current to make them visibly light up - possibly this would speed up their lighting up time?. I can't say I've ever heard of it being done, but it's perhaps worth investigating?.
In about 1980 the company I worked for suddenly started selling large telephone systems. The business phones of the day used light bulbs instead of LEDs. The bulbs kept burning out, because they flashed continuously when ringing or a call was on hold. The bulbs couldn't take the abuse of heating and cooling so much and failed frequently.

After I got tired of replacing lightbulbs, I added pre-heat resistors to them. I think those phones are still with the same replaced pe-heated bulbs today! :lol:
 
Re: not exactly the solutions that i needed

audioguru said:
After I got tired of replacing lightbulbs, I added pre-heat resistors to them. I think those phones are still with the same replaced pe-heated bulbs today! :lol:

It's very hard to have an original thought these days! :lol:
 
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