same spec,,, +/- 5% ...i can't remember the exact price, cheap though. I'll check tomorrow if i have time when picking up my car.

 

Well, find me any of the following:

• 5.1v 1 watt zener diodes (1% tolerance)
• 5.2v 1 watt zener diodes (2% tolerance)
• 5.3v 1 watt zener diodes (5% tolerance)

The minimum voltage tolerance can not be below 5.0 volts, thats the biggest spec. PM me with any pricing and availability.

 

will do

 

I would prefer the min to below 5v, the max shouldn't be above 5v.

Not until we are sure above 5v is ok for the ecu

ps Jamie I got your harness in the mail I just havn't had the time to install it yet :P

 

Fair enough. How exactly can you find out if the ADC can handle a 6v input anyways? I'm reading up on IC's and stuff so maybe I can find an average acceptable voltage range for these type of inputs. Most of that stuff is industry standard for the most part.

The harness got there rather fast considering it was relatively cheap to ship it to Australia Let me know what you think of it.

 

EDITED this original post:

So basically, the real range we want to be in is between 2.7-5.0 volts for map switching. Anything BELOW 2.7 volts and the ADC input is 'incertain' its a true signal and isn't just line noise. There is a small window that is allowable over 5 volts but its no more than 5.25v-5.50 volts for most IC's I looked at.

I bench test every harness I make so I will not allow any to ship out that exceed 5.2 volts on the test bench Most have been in the 4.75v-5.0v range. I will actually add a note with the shipped packaging of the actual tested output voltage with each harness too.

 

so the 5.1+ diodes wont' be used? Lower votlage diodes?

 

Well, I'm researching but going as high as 5.25-5.5v is usually within spec's of most IC's I have looked into. Ideally we want to be as close to 5.0v without going over that. If we go with a standard 4.7v zener diode (5% tolerance) the range is 4.4-5.0v which is best I think. Like I said, any of the 5.1v zener diodes I used even reached greater than 5.0v (gotta love tolerances). So maybe its best to use a 4.7v zener diode.

Though I don't see any REAL issues using the standard 5.1v zener diodes that are readily available at any RadioShack store for the DIY'r. I will change to the 4.7v zener diodes solely as an extra precaution.

 

yeah 4.4-5 is fine, I mean that still gives us plenty of range for interpolation later.

ps I assume you are hooking a 12v source? ie you can't be going from 3.3v input to 5v output :P

 

You get the harnesses voltage source from the ECU's +12v ignition pin. Well, we'll have to really mess with the ADC input to see how it reacts to varying input voltages but from what I have read, it generally will be most reliable from 2-5v. Since it isn't a standard logic input which is either ON or OFF, I think we may be able to use a majority of the 0-5v range.

 

I wonder if you could configure this ADC input to replace the front O2 signal with a linear wideband O2 sensor 0-5v output? Or if we can find out if the front O2 input is capable of 5v. I know the hondata guys figured out how to do this. We need to find more ADC inputs,lol.

 

I think that tephra has my rear O2 sim patch in his v5 ROM, so rear O2 ADC is already available to anyone using his ROM. The fuel temperature input can probably also be safely simulated without screwing up the evap emissions system. What do you want more ADCs for?

 

Well, after googling some more I noticed that using the WB signal doesn't help anything except make it easier to datalog your WB readings on some setups. Since we can easily log most via evoscan its really not needed for us.

I definitely want an ADC input dedicated to flow sensor monitoring and another for the actual failsafe map switching. Using the rear O2 for flow sensor monitoring will be great if it can accept the same 0-5v analog input as the unused ADC input you found.

If we have the inputs available, we'll think of cool things to do with them lol.

 

yeah im going to hook my wideband up to the rear02.

just need to find out if the heater circuit will be overloaded by the wb heater...

 

What wideband do you have?