Knock sensing ideas and circuit designs

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jharvey
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Re: Knock sensing ideas and circuit designs

Post by jharvey »

Here's a link, to some links about knocking.

http://www.diyefi.org/forum/viewtopic.php?f=9&t=463

There is an article a forum member posted. It's very good about describing many aspects of knock. Many of the items linked to will explain knock vs detonation vs general engine noise.
Pilt
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Have you concidered the TPIC 8101 or HIP 9011 for Knock?

Post by Pilt »

Hi,

Havent been on here for a while but came back and see you didnt like the idea of using the TPIC 8101 or HIP 9011 (same IC) for doing the knock sensing?

What is the issue with windowing? Because if you are controlling ignition then you know when to look for knock and you can determine which cylinder it is on if it occurs?

The reason i reckomend these IC's is we use them in our ECUS. One ECU we make using this IC is being used on all the cars in the American Le Mans series (i think). Another ECU we make is for an Aircraft engine and this utilises this IC (one IC works for 6 cyclinders) so it must work well!

I have not looked at the software implementation (but will see if i can!) but cant see it being overly complex.
I just imagine this IC would be easier to utilise as it would cover most cases and does not require filter design etc.

Cheers

Dan


(Sorry ment to post this in the Knock thread but it ended here!) Feel free to move it
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Fred
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Re: Knock sensing ideas and circuit designs

Post by Fred »

The first time these were brought up I was anti them because they require an ADC. Now I've backtracked on that I can't see why not really. I'd have to look into it again, but it shouldn't be a problem. Windowing on the other hand could be more tricky, but not impossible.

May I ask, what are "our ecus" ?

Thanks for your input.

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Re: Knock sensing ideas and circuit designs

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Well im a Test Engineer at the company that supplies the Formula 1 grid with all its ECU's. I would rather not put the name in case someone googles it and ends up here........

Anyway I develop python to control the test equipment for production test. I had a look at your development of the Free EMS software and it looks good, might have to have a play with it myself.

The only ocasion I can see where windowing might be a problem is if you have two sensors on each bank of a V8 and were using a Distributor to do the ignition. But then if you are trying to knock sense and are still using a distrubtor seems it would be better to get a decent ignition system first!

I havent looked at your hardware designs yet but if you have ignition drives on the board then this is not really a problem. If you are looking for good driver IC's i must recommend the Infineon automotive parts as they have all sorts of in built protection (short, overload, etc, etc) and we test them pretty rigourosly and they are v.hard to break
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Fred
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Re: Knock sensing ideas and circuit designs

Post by Fred »

When you say Free EMS software, do you mean the firmware, or Aarons python tuning app?

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Re: Knock sensing ideas and circuit designs

Post by Pilt »

Python tuning app. HAvent looked at much else yet.... Always too busy!
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Re: Knock sensing ideas and circuit designs

Post by jbelanger »

Pilt wrote:I havent looked at your hardware designs yet but if you have ignition drives on the board then this is not really a problem. If you are looking for good driver IC's i must recommend the Infineon automotive parts as they have all sorts of in built protection (short, overload, etc, etc) and we test them pretty rigourosly and they are v.hard to break
Are those available to DIYers?
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jharvey
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Re: Knock sensing ideas and circuit designs

Post by jharvey »

Do they one that has over voltage protection? Something like the PIP3104 where OV trickles a little to the gate to drain off current keeping the voltage spikes down due to inductive spikes.

Hmmm perhaps we're a bit off topic from knocking.
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Re: Knock sensing ideas and circuit designs

Post by davebmw »

The TPIC 8101 and HIP 9011 are an ideal solution if we can get them talking to the XDP chip. :D
I haven't really looked into it in much depth as it requires a more software biased individual. ;)
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Re: Knock sensing ideas and circuit designs

Post by thebigmacd »

Microsoft? :)

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