Preston's Element 14 BOM Attempt

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Fred
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Re: Preston's Element 14 BOM Attempt

Post by Fred »

One more thing, R251, 1k between header and SM pin, this needs to have a pull up to 5v as the internal one will be getting disabled in future SM versions. R251 can stay as is, but add a 10k or 1k or something in between 1/4 TH resistor to mod this with.
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Re: Preston's Element 14 BOM Attempt

Post by Fred »

Hello Preston!!
Only one day late, here is my review of your BOM:

BRV, C31 0.1uf >> 0.22uF

AAP & MAP:
  • U6, exclude from off board MAP option
  • Copy paste errors between two pages
  • Component equivalent order differs making comparison hard
  • One has three NC/two Jumper and the other has four NC and one jumper, should be same, or not???
RPM inputs, looks good, but doesn't specify:
  • that zeners are NOT to be installed
  • that only one of the resistors to the CPU is to be installed
  • that it's to be 1k
Fuel Pump drive has mod removed and looks good!

TPS, CHT, IAT, MAT unchanged look good.

TPS seems to have only one cap, is this true or missed?

Injection, orange 100k to ground mod = good. Needed if using XG code, might be needed for non-XG code.

Ignition:
  • r228 OR r229, something for the instructions, ordering a spare is fine.
  • I don't see mention of a high power 12v pull up resistor to be used with the FET for ignitor use?
Primary parts changed a lot, but attempting to review anyway:
  • LOTS of missing part numbers
  • R251 and SM stuff still needs pull up mod described and added.
  • Ordering 3 different clock caps is a GOOD idea! Well done, thanks. Outlines are nice too, how about one for PLL?
  • C95,98-102 say 0.2uF but are probably 0.22uF, minor detail, but... :-)
  • Also, the above caps are connected wrongly, note this in the BOM in short form, to be expanded in instructions.
  • Checked crystal part num last time, and it's good.
  • typo in C93 which should be 6.8nF not 3.8nF
Please do not add rows/cols or move things around except AAP/MAP part ordering as requested.
I do a visual diff by switching windows and moving stuff around screws this up for me...

Cheers,

Fred.
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Re: Preston's Element 14 BOM Attempt

Post by Preston »

I will get onto the changes/checks, should have it done in a couple of days.

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Fred
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Re: Preston's Element 14 BOM Attempt

Post by Fred »

DOH! Those "CHECK OLD NOTES" were for me! :-( Sorry, I should do that now and edit... Fixed!
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Preston
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Re: Preston's Element 14 BOM Attempt

Post by Preston »

My bad on the delays, the changes have now been made! Were almost there.
Fred wrote: BRV, C31 0.1uf >> 0.22uF
Done.
Fred wrote:AAP & MAP:
  • U6, exclude from off board MAP option
  • Copy paste errors between two pages
  • Component equivalent order differs making comparison hard
  • One has three NC/two Jumper and the other has four NC and one jumper, should be same, or not???
Checked all NC/jumpers correct, MAP is comprised of more components. Added missing resistor R133 which is a NC. (Sorry Fred but a line had to be added :) )
Fred wrote:RPM inputs, looks good, but doesn't specify:
  • that zeners are NOT to be installed
  • that only one of the resistors to the CPU is to be installed
  • that it's to be 1k
Will be documented in Puma how too, I will keep them as reminder notes till then.
Fred wrote:Fuel Pump drive has mod removed and looks good!
Done.
Fred wrote:TPS seems to have only one cap, is this true or missed?
Yes one cap is correct, however it was a fantastic way to alert me to the fact I had used the annotes from schematic page 24 <---Wrong! corrected these and traced on PCB now correct, components them selves didn't change. Schematic pages updated in BOM. Please double check my work as flicking between these schematics is doing my head in.
Fred wrote:Ignition:
  • r228 OR r229, something for the instructions, ordering a spare is fine.
  • I don't see mention of a high power 12v pull up resistor to be used with the FET for ignitor use?
To be discussed/confirmed, Fred hit me up about this one.
Fred wrote:Primary parts changed a lot, but attempting to review anyway:
  • LOTS of missing part numbers
Done!
Fred wrote:
  • R251 and SM stuff still needs pull up mod described and added.
As per about to be documented in Puma how too.
Fred wrote:
  • Ordering 3 different clock caps is a GOOD idea! Well done, thanks. Outlines are nice too, how about one for PLL?
Done! Should be much better now, anything to make it easier to follow.
Fred wrote:
  • C95,98-102 say 0.2uF but are probably 0.22uF, minor detail, but... :-)
Good spotting, yes that was just a typo :) now corrected.
Fred wrote:
  • Also, the above caps are connected wrongly, note this in the BOM in short form, to be expanded in instructions.
As per above will be documented, just a note for now.
Fred wrote:
  • typo in C93 which should be 6.8nF not 3.8nF
Corrected.

Anyone following this is welcome to chime in, not just Fred.

Home stretch! yay
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Re: Preston's Element 14 BOM Attempt

Post by nitrousnrg »

As Fred wishes:



<nitrousnrg> FreeAir_: I think that the capacitorss for the crystal should be from 18pf to 27pf, and the bom lists a 33pf option. I could be wrong, and its not a big difference but I thought its better to mention it
[12:35] <zyp> do as specified in the crystals datasheet
[12:36] <zyp> I used a week to debug a weird problem related to wrong crystal loading half a year ago
[12:36] <nitrousnrg> also, I never used those PLL values for the capacitor
[12:37] <nitrousnrg> I see, capacitor too big?
[12:38] <zyp> no, too small
[12:38] <FreeAir_> nitrousnrg: thread!
[12:38] <zyp> it was a 16 MHz capacitor used for a 2.4 GHz transceiver

Also watch out the reverse current drain of those schottkys
http://www.onsemi.com/pub_link/Collater ... 0LT1-D.PDF

Figure 4 seems ok, and figure 2 is very different, it says it can draw from 0.3 to 1mA. I think figure 2 is LT1 and figure 4 for LT3.

Back to work, only 5 weeks left.
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Re: Preston's Element 14 BOM Attempt

Post by nitrousnrg »

Nevermind, I read 25°C instead of 75°C. The schottky is good at reasonable temperatures. I've to revise the circuit in order to be operational at higher temps :)
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Re: Preston's Element 14 BOM Attempt

Post by Preston »

Thanks Marcos,

I think we can agree on the range of values that need to be used in the clock and PLL circuits so there is no point in going through all the math again. A lot of the 'tuning' of these circuits can only be done via trial and error as PCB layout affects it operation... So being that Marcos and Fred are the only two that have a working board, your evaluations are all we can go by in regards to stability and operation :) if you both have used different parts.

I have further investigated the crystal X3 today and realize that this is a NO go! The current chosen component has the opposite footprint to the Puma board. Asides from this the high ESR did concern me, the datasheet did not state a typical ESR only a maximum which is annoying. I will find a suitable replacement.

Marcos what is the part number of the crystal you used?

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Preston
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Re: Preston's Element 14 BOM Attempt

Post by Preston »

Correction! sorry guys X3 is ok.

The data sheet labels the pins viewed from the underside of the component. This is easily mistaken as the PCB footprint layout ---> the PCB footprint is a mirror of this, so were good.

Too many hours staring at this :)

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Re: Preston's Element 14 BOM Attempt

Post by Fred »

Preston, one catch, when saving xlsx docs and exporting to html, it's really important that you move to the first page before doing so. The html in the repo puts you on the ignition sheet by default. No big deal in the repo, but needs to be right before uploading to a website. Same goes for the xlsx. Back to checking...
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