Jon 74 260Z Posted December 17, 2008 Share Posted December 17, 2008 How would you integrate this display driver to generate the sequence he wants? It takes an analog reference voltage and chooses the display based on the level. Are you thinking of using the 0_/---12v transition from the flasher? A (dis)charging circuit? Yep, use the 0/12v signal from the flasher to control a charge/discharge. The ref voltage is simply a bypassed R-divider -- easy (and it would track your charge/discharge). It's been a while since I've had to look at the App Notes for the 3914, but my memory says that they had a lot of good info that would be applicable here... Anyway, according to Google you can supply a 555 timer with between +3 and +15v. Same for the 4017 decade counter. That means you don't need the 7805 regulator. You're right on the voltage range of these devices BUT... you're gonna need some protection circuitry for the hellacious transients that occurr in a car environment. (See comment below.) Linear regulators are pretty robust so in terms of component count and BOM cost, it's a wash as to the choice here. I'm sorta leaning towards the microcontroller here, because you can solve a bunch of problems with code. Like I said, I'm certain someone can make this approach work. I wouldn't chose this method. Reading through the automotive requirements that an IC has to withstand makes me chicken to use any kind of clocked circuit. Analog circuits are self-correcting when it comes to noise spikes whereas digital circuits get fatally confused. But then again, I'm an analog guy -- what do you expect me to say? Quote Link to comment Share on other sites More sharing options...
AK-Z Posted December 19, 2008 Share Posted December 19, 2008 Try searching for a 4017 IC and 555 IC. You can piece together a LED sequencer. If you want a faded effect, you will need a series of transistors and capacitors for each sub-circuit for each line of LEDs. It will give you faded filament effect. You can get up to, I think, 18 LED sequences. The problem will be when you have the hazards on and the other indicators, since you will have to run the whole thing with out a flasher. FYI: Do Not use a 955 IC to sub for a 555 IC. Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted December 19, 2008 Share Posted December 19, 2008 All these posts utterly fascinate the hell out of me. I have zero knowledge of things like this (circuits / micro controller etc.) and envy any and everyone who does... I dig reading this stuff, only wishing I had the gift of understanding it... Quote Link to comment Share on other sites More sharing options...
ZZZeee Posted December 19, 2008 Share Posted December 19, 2008 These look pretty nice... http://www.mustangproject.com/ProductDisplay.aspx?id=1d866817-ec66-401a-b575-2973f2a0e796 http://www.mustangproject.com/ProductDisplay.aspx?id=a19bb8db-ef8a-4548-b18f-d2878aaac176 http://www.mustangproject.com/Catalog.aspx?search=MP-9001&category=ALL The second one down in the next link does exactly what you want... http://www.mustangproject.com/Catalog.aspx?category=68642387-6653-4218-935e-89619ca5f35a&sub=c42a205e-f37c-4025-8a87-cabc0c31af59 Or maybe something like this (both links below)... http://www.globalsources.com/gsol/I/DMX-controller/p/sm/1006868280.htm and http://glorious-led.manufacturer.globalsources.com/si/6008828513849/pdtl/LED-light/1008350253/LED-Light-Fixture.htm Here's another... http://www.mustangproject.com/ProductDisplay.aspx?ID=4b22eb3c-1505-4fc2-8209-2734f257fb46 The following site has some cool stuff... http://www.spaghettiengineering.com/comersus/store/home.asp Maybe this cool truck tailgate light can be adapted... http://www.autoanything.com/lights/65A4299A0A0.aspx Quote Link to comment Share on other sites More sharing options...
AK-Z Posted December 19, 2008 Share Posted December 19, 2008 http://www.circuitdb.com/circuits/id/154 There you go. But to have the LEDs in constant (on) as the sequence progresses, you will need to add a few more parts. Suggestion: test on a bread board, then build your own PCB. You'll be better off doing things right the first time. Also: you can look for a knight rider scanner kit. Depending on which kit you you get, you will have to remove and rearrange the LED orders. Another better alternative is to find a suppler of ambulance turn signals and try to rewire the LEDs or wiring it to an existing fabbed circuit. BTW. those items are WAY OVER PRICED IMO. its only a 3 trigger sequence to 3 LED arrays. the effect that you get with a 4th link is only 4 parts per array (inless you have each LED with it. And the transistors act as a type of relay, so it doesn't necessarily need to be run off of the same power source as the controller circuit). That effect can be found here (step 4: driving the LEDs) http://www.evilmadscientist.com/article.php/CylonOLantern Hope this helps Quote Link to comment Share on other sites More sharing options...
RPMS Posted December 19, 2008 Author Share Posted December 19, 2008 So how would you power this thing? I'm not too familiar with using LEDs for tail lights. Are they +12v? These circuits are TTL and operate at +5v. You'd need to factor in a 7805 regulator as well. You can use +12v transistors to drive your LEDs as long as +5v (-0.7v if you use a diode on the output of the counter IC) is over the Vt of the transistor. Simple right? Enjoy the stew... Mmm... Tasty.... I'm using LEDs for turn signals in the rearview mirrors, and as turn indicators in the instrument cluster. What I've been doing is dividing 14.6 volts by the power requirements of each LED, and using that number of lamps in series. I think for the turn indicators I'm using five lamps. It's probably not the *right* solution, but it's easy, and it seems to work. Regarding the power supply, I was considering just using a resistor in series with the input power, and choosing whatever value dropped the voltage smack in the middle of the operating range of the IC. Is that naive? Quote Link to comment Share on other sites More sharing options...
RPMS Posted December 19, 2008 Author Share Posted December 19, 2008 All these posts utterly fascinate the hell out of me. I have zero knowledge of things like this (circuits / micro controller etc.) and envy any and everyone who does... I dig reading this stuff, only wishing I had the gift of understanding it... I'm with you there, bub! I only learn as much as I need to to finish a project, then I promptly forget it. Doing repairs on my own projects is can be something of a challenge. Quote Link to comment Share on other sites More sharing options...
AK-Z Posted December 20, 2008 Share Posted December 20, 2008 Mmm... Tasty.... I'm using LEDs for turn signals in the rearview mirrors, and as turn indicators in the instrument cluster. What I've been doing is dividing 14.6 volts by the power requirements of each LED, and using that number of lamps in series. I think for the turn indicators I'm using five lamps. It's probably not the *right* solution, but it's easy, and it seems to work. Regarding the power supply, I was considering just using a resistor in series with the input power, and choosing whatever value dropped the voltage smack in the middle of the operating range of the IC. Is that naive? Usually with electronics like this you will want a regulator of some sort ( as you said) and you want to keep into account the amperage you want the circuit to handle. With my little carupter side project (failed ) I burned a few old HDD because of the amperage (its was a strange setup and ran through the computer's existing PSU [12v, 13.3 amp]). I suggest building wattage regulator circuit (voltage and amperage regulator). Another alternative is to build the light circuits to run on 5v and buy a bunch of those USB car chargers to use as a regulator. If you can't find a schem for 5v, then you can easily find one for 6v or even 9v and then it would be a matter of taking apart those USB charges and replacing one of the resistors to the appropriate one, to change it to the correct voltage. Quote Link to comment Share on other sites More sharing options...
Gearshredder Posted December 27, 2008 Share Posted December 27, 2008 well i found something around the web: http://web-ee.com/schematics/electro-optics/led-turn-signals/ and the pdf from the same site: http://web-ee.com/images/SequencedTurnSignals.pdf Quote Link to comment Share on other sites More sharing options...
AK-Z Posted December 27, 2008 Share Posted December 27, 2008 well i found something around the web: http://web-ee.com/schematics/electro-optics/led-turn-signals/and the pdf from the same site: http://web-ee.com/images/SequencedTurnSignals.pdf Looks promising, but with out any actual pic or vids of a test circuit its all guess word Quote Link to comment Share on other sites More sharing options...
Gearshredder Posted December 28, 2008 Share Posted December 28, 2008 well then make us happy i could manage something up but im busy lol Quote Link to comment Share on other sites More sharing options...
AK-Z Posted December 28, 2008 Share Posted December 28, 2008 well then make us happy i could manage something up but im busy lol Sure.~~ I have more important things to do to the car before I start accessorizing it. Quote Link to comment Share on other sites More sharing options...
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