will this circuit work?

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k1pp3r

[H]F Junkie
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Not to sure how many of you here are familiar with the suspension system on a 3000GT VR4 so i will explain it in a nutshell.

the ECS will adjust all four shocks individualy from soft to medium to hard depending on how the car is driven, and how brakes are applied.

My idea is to make indecator lights for the 3 different settings using a tri color led, red, blue, green

Green=soft
Blue=Medium
Red=Hard

If i am reading my maintainence manual correct the way the struts adjust is this

constant 9V = Soft
9V + 5V = Medium
9V + 5V + 5V = Hard

Will the following curcuit work for this, if you need more infon on anything let me know

bates15-strutcircuit.jpg


Link to the NEC IC
 
cant see the schmatic, and you have no configuretion for "soft". also, i assume that there are 3 wires, or are you talking PWM? please elaborate
 
what are you seen, shows up for me, are you getting a red X?

can you see it now, i changed hosts and format
 
k1pp3r said:
constant 9V = Hard
9V + 5V = Medium
9V + 5V + 5V = Hard
Click to expand...
i think you made a typo here. one has to be soft. i can see the pic now, very wierd. before i had a red x
 
yeah youve deffenatly overcomplicated it. i can draw up how to use like 4 and gates to do the same thing. im not even going to mess around with figureing out what a 3 stage d latch would do.... if your intrested in the gate version let me know
 
theshadow27 said:
yeah youve deffenatly overcomplicated it. i can draw up how to use like 4 and gates to do the same thing. im not even going to mess around with figureing out what a 3 stage d latch would do.... if your intrested in the gate version let me know
Click to expand...

That would be great, i am not an electronic engineer so any help is awsome, also where can i get these gates! and did i overcomlicated it to the point it wouldn't work or would it still work lol
 
okay from a engeering standpoint, here is what your input looks like:
Code: 
input:
a b c
0 0 1 = soft
0 1 1 = med
1 1 1 = hard

the easy way to do this is with 3 'AND' gates and 6 inverters.
and gate (4) 7400
inverter (6) 7404
you can obtain them from www.digikey.com, www.mouser.com, or www.newark.com very cheaply.

heres my circut:
suspentionled.jpg

sorry i got lazy and didnt want to draw it up in autocad

EDIT: my friend just asked me what the little numbers next to each line were. they are pin numbers for the 2 chips. you should be able to wire it right up, all the pin numbers are right. dont forget power/ground pins. both of these chips can run directly off 5v, so if you cant source 5 v externaly you can get a 5v regulator (at radio shack) and hook up the 9v input. that way if for some reason it malfuntions the led will go off (no light=problem). my circut does not use the 9v line for anything at all.
 
SacLANd said:
they're a buffer. they drive the chips.
Click to expand...

so why isn't there one before the third and gate, sorry i'm just trying to understand this a little more than i do now, thanks
 
theshadow27 said:
okay from a engeering standpoint, here is what your input looks like:
Code: 
input:
a b c
0 0 1 = soft
0 1 1 = med
1 1 1 = hard

the easy way to do this is with 3 'AND' gates and 6 inverters.
and gate (4) 7400
inverter (6) 7404
you can obtain them from www.digikey.com, www.mouser.com, or www.newark.com very cheaply.

heres my circut:
suspentionled.jpg

EDIT: my friend just asked me what the little numbers next to each line were. they are pin numbers for the 2 chips. you should be able to wire it right up, all the pin numbers are right. dont forget power/ground pins. both of these chips can run directly off 5v, so if you cant source 5 v externaly you can get a 5v regulator (at radio shack) and hook up the 9v input. that way if for some reason it malfuntions the led will go off (no light=problem). my circut does not use the 9v line for anything at all.
Click to expand...

huh i don't think i'm reading the correct, how can you have 3 setting with only using 2 inputs, dang i need to studie these things
 
okay only 2 of the lines change so you dont need to use one that alwase stays the same, right :)

its very important to understand how didital logic works. theres a decent tut http://www.williamson-labs.com/480_logic.htm

the inveter flips the signal, if the input is "1" the output is "0", and visa versa

the NAND gates (stands for Not And) turn on only when both inputs are "0"
 
theshadow: seams like it'd be easier to use a cad package designed for electronics, rather then MSpainting all that. you can get a small (15mb installed i beleive), free SPICE program at http://www.linear.com/software/
 
haha, mine was done in ms paint, only took about 10 minutes, i'll have to find some time to read that artical
 
on the and gates, do both incomming wires have to be powered for the gate to open?
 
this is the theroy of a NAND gate (the gate shown)

a=input 1
b=input 2
x=output

a b | x
0 0 | 1
1 0 | 1
0 1 | 1
1 1 | 0

here is the theory of the inverter (the triangle show)

a=input
x=output

a | x
0 | 1
1 | 0

where 0 = off and 1 = on
 
OK, i think i get it now


bates15-NANDlogic.JPG


In this pic taken off your scematic

when supply A & B are off the inverters give the NAND gate power and close the gate which causes inveter C to supply the led with power, is this correct?
 
LOL.. this is too funny...

if you want to make logic schematics

google for Altera Quartus II, very good logic design Software.. it's free.. i designed a CPU using this bad boy.
 
YOU can also use a multiplexer to implement the logic.. would be less wiring.. how are you doing this anyway?
 
RancidWAnnaRIot said:
YOU can also use a multiplexer to implement the logic.. would be less wiring.. how are you doing this anyway?
Click to expand...

by etching a PCB and a soldering iron, and i don't think i need to design a cpu,
 
LOL.. i never said you were gonna design a CPU.. i'm jsut saying the program let's you make much nicer looking schematics and stuff...

just plot down some logic gates and then post it on the site... i wasn't really directing it to you though.. it was for the dude that had the hand drawn thing..
 
yeah, i think i get it now, i'm gonna draw up a better scematic tomorrow and post it, then i should get to work, only i will need 4 of these circuits, one for each strut,
 
k1pp3r said:
OK, i think i get it now

when supply A & B are off the inverters give the NAND gate power and close the gate which causes inveter C to supply the led with power, is this correct?
Click to expand...

yep. you got it. wat do ya think? pretty cool....

if you need to make 4 identical PC boards, check out pcb123. you can get 4 2 layer boards made up for about $20, and they will give you free software.
 
Final Scematic and Chip selection

NAND GATE
http://www.fairchildsemi.com/ds/74/74AC00.pdf
Which package number should i get? And can i use them with DIP sockets?
will this chip act as a buffer so i dont fry my ECS in anyway?

INVERTERS
having a hard time finding, can you point me to some?
EDIT: I think i found one http://www.st.com/stonline/books/pdf/docs/4936.pdf

Should i go ahead and put fuses on the incoming 5V lines, or should the fuse for the ECS computer take care of that?

And the scematic, yes it is in ms paint, lol

bates15-strutnand.JPG
 
74ac00 you will want P(lastic)DIP package, unless your into surface mount (pain in the ass)

this chip will not draw enugh current to mess up your cars computer... it is very well protected agienst just about anything that can happen to it (including lightning strikes... :rolleyes: ....realy).

if you are concerned about the health of this circut, you can place 5.1 volt zener diodes "backwords" (anode ->a cathode ->gnd // anode -> b cathode -> gnd) and this will protect it agenst voltage spikes (at startup, what ever) and agein will not mess up your ECU. fuses are a bad idea, 5 volt fueses are rare, and they are ment for high current shorts, not small voltage spikes.

agien for the 4936 hex inveter you wont need any aditional buffers (itself acts as a buffer) and you found the right chip. again, pakage is DIP.

the schmatic looks good. if your building 4 of these, i would sugest putting them all on one board, and hooking into A^x and B^x pretty close to the ECU, like 3 inches out from the connector. this way you will have to run the least number of wires, and they will all be in the same place if you choose to dissconnect it at a later time.

im looking foward to see how you do this. it sounds like a great mod. dont forget pics!
 
theshadow27 said:
the schmatic looks good. if your building 4 of these, i would sugest putting them all on one board, and hooking into A^x and B^x pretty close to the ECU, like 3 inches out from the connector. this way you will have to run the least number of wires, and they will all be in the same place if you choose to dissconnect it at a later time.

im looking foward to see how you do this. it sounds like a great mod. dont forget pics!
Click to expand...

Well the ECS computer is mounted in the back of the car, i'm thinking i'm gonna run from there to the board, either that or from each of the 4 struts back to the board (a few more runs) i need to look at the wiring harness to see if i can tap in with out cutting any wires, or thoes crimp things, we'll see what i come up with, should be cool. And i will have to take a movie clip of it to

Hey does anyone know where i can get thoes 3 pin fan headers, they would be perfect for quick connects and disconnects from the pcb

Guess tomorrow its a trip to the rat shack, see if i can find a big enough Copper board
 
yeah personaly i would tap into the harnass using the 3m quicktap connectors with 18gauge wire, then cut the new wire about an 6 inches from the tap... you should have 8 wires. then id take cat5 (easy because of the pairs, 4 sig + 1 power) and run it up to the front.

as for the board, i wouldent advise etching your own, its a royal pain. 2 circuts will fit on each of these and you can get a little bit of 20 gauge hook up wire to run each connection manualy. there arnt that many connections.

as for your final circut...
finalstrut.jpg

some minor additions.
* 5v voltage regulator... get it at radioshack
*5.1 volt zener diode (protect the chip) get it at radioshack
*you can get all the resistors and wire at radioshack too

so the only components youll have to order are the chips. digikey.com or mouser.com
 
it is an optional componet... its a capacitor to filter the incomming DC current (if it drops below 5v for a fraction of a MilliSecond the capacitor will compensate) to keep the chips a little happier. because this is a constant source logic circut, it realy wouldent matter if the chips reset, but its a good idea to throw it in there anyway. i forgot it on my notes above, my bad. heres the spec:

* 1uF (microfarad) cap http://www.radioshack.com/product.asp?catalog_name=CTLG&product_id=272-1434

you basicly want to put it across the power pins of any IC
 
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