Preston's Element 14 BOM Attempt

[Fred]

El Presto has been doing some GREAT work on a BOM for Spin 1 that makes sense and is usable! You can find it here:

https://github.com/presto/Puma-Bom-Element14/

I reviewed it just now and found the following things:

• all diodes for adc protection should be schottky, not normal 1n4148 units. eg d35 in brv tab.
• check d33 d34 c30, why not used? same on aap c19 d31 d32
• map and aap both can't exist with tabbed package. aap if installed with normal map must be tabless package.
• both map and aap can be substituted for off board map units from toyota, honda, gm, etc
• no mounting for either map or aap.
• aap should have barb for routing to correct pressure zone on car.
• aap is unused at this time, code is not a priority right now, but shouldnt take long to implement if/when someone needs it
• on rpm page, r212-r216 might take 1/4w but will really get that hot and should probably be taken off board into loom as trying to stand bigger packages on end on the smd pads just rips the pads off.
• all caps that aren't tantalum should be X7R in final, not critical for spin 1, though.
• fuel pump page, r66, what is that for? mine isn't populated, but it could be a good thing to have. R68/C37 should not be populated. No mods are required for d46 and r67, cept maybe the value of r67 and the part number of the d67 led. Drive fet is not included in this page and should be.
• CHT stands for Cooland/Head Temperature
• CHT page, R148 should be left out (this is in the instructions that i wrote!! read them again and check the rest of your work.) why the hell would you want a zener there? lol
• afaik, no zeners should be installed on the board.
• R147 should be 1% MF as it needs to be accurate
• all resistors should be 1% MF as they are cheap and easy to get and just better in every way
• CHT 3 caps listed, 2 used, one not, topology? I don't understand.
• CHT should have two schottkys also, where are they?
• All complaints about CHT for MAT and IAT too
• MAT unused for foreseeable future, but good GP temp input
• TPS value changes not colourised.
• TPS 1n4148 must go and be replaced by schottky as above
• Injector page, major hackage required whether low or high z is built. low z doesnt use fet, high doesnt use chip. recommend only high z, but marcos may have a set of hacks for low z?
• Injector page, didn't check your part numbers, but assume they are good from previous discussion.
• Ignition, just thinking, could do it the same was as the hotel with a 100 ohm pull up to 12v (or 5v) and the FET pulling down to ground. XOR can be used to correct polarity. Use cheap fets for this, logic level still required but load should not be significant (only the 100ohm resistor...)
• Ignition, why zener?
• Ignition should consist of cpu > 1k > xor > 1k > fet (with 100ohm pull up) (with LED setup on either output of XOR or output of FET, whatever pcb allows for)
• XOR resistors can be 1k to share parts. I relaxed my nazi 1.6k demands some time ago. It wasn't realistic. 1k is on my board too.
• Power Primary Parts (PPP :-p) all red stuff seems good, didn't check non red stuff.
• Didn't check USB, but needs hackage to power from USB not from ECU, LEDs need hackage too as they are connected wrongly.
• Didn't check CPU clock stuff, needs checking.

Presto, great work, I feel like it's close, similar to RavAGE, all of a sudden. Let's get yours nailed and out there too, and preferably banged into freebombs so it can be easily used online, and we'll be away laughing, with upto 37 puma spin 1 users :-)

Fred.

[Fred]

I'd appreciate review from Marcos and Jared on this document and from Marcos, Jared and Preston on my feedback! Others are welcome too. It'd be great to see some spin1 units up and running. 2 down, 35 to go.

Fred.

[jharvey]

I can't open the newest versions on xls. I have XLS 2002, I believe Marco doesn't have it at all, but can open older versions of xls with OO.

[jharvey]

D33, ect, shouldn't those be TVS diodes? Schottky's can have slow response times.

R212, ect probably not a bad idea to put in the loom, but beware the heat, it could melt wires, as those are rated for a much lower temperature. I seem to recall the typically application will use lower power than the max wattage, which is when sustaining a 12kRPM VR. I expect even with the 1/8w 0805's in there, you'll be fine for a typical build. They wouldn't be good for the Isle of Man race but would be good for a drag strip. Wasn't your old car a CAS?

I don't know if X7R is required for most caps, most could likely be Y7P as they are often just decoupling caps and bulk caps. X7R's are often low enough cost and it won't hurt to use them, so it's not a bad suggestion, but I don't think it's required. Caps like C88, C123, C77, C93,94,95,96,97 might benefit from a tight tolerance. However if we are really concerned about it, we really should parallel two caps such that one has a + temp co-efficient and one has a - temp co-efficient. That's really the only chance you have of getting a consistency uF over a wide temp range.

The original Fuel pump page didn't have R66 on the fuel pump page. Also the current PDF pump page doesn't have R66. I'm confused about what R you are referencing. http://puma.freeems.org/docs/Puma_spin1_schematic.pdf Looks like drawing rev control is buggered. I see several different copies of rev A.07.

The CHT, had a stab at the components, and mostly placed pads for what ever components we thought it might need. Marco was attempting to combine the AN protect and such in one schematic. I agree that R148 shouldn't be populated, however it could be used for transient suppression diode. C75 is just bulk, and C73,74 probably want some real world testing to really know what they should be. If we want a better guess about what parts should be there, perhaps we can simulate it. If anyone knows how to get a spectrum display out of QUCS, I'd be willing to give it a try. I'm sure QUCS can do it, I'm just ignorant at the moment.

[Fred]

I can't open the newest versions on xls. I have XLS 2002, I believe Marco doesn't have it at all, but can open older versions of xls with OO.

I have version 3.3.2-2 of LibreOffice (fork of OpenOffice) and it opened it just fine, including all prettiness, or so it seems. Good feedback, thanks! :-) Is the clock stuff good?

[jharvey]

Oh great, then you can do a save as to get it into a format I can use.

[Fred]

OpenOffice/LibreOffice is available on all platforms for free! Not only that, but the lates M$ Office crap can open OO docs! :-o

[Fred]

CHT definitely leave R148 off and definitely NO zener there. The cap that is left out should be left out, it connects ground to 5v, but in a bad place. I'd still like to see where the schottkys are for CHT and friends, though. Which page of the original schem? EDIT 48! Those compnents should be listed on each of those circuits too so that we get a full cpu pin to connector pin view.

[Fred]

This is one reason why Puma has left everyone confuzzled!



5 of the 11 components included for a single temperature sensor are either un-needed or hurt performance in one way or another. I reckon Puma could have been even more sparse, or used larger footprints for various things if some of this stuff had not been put on. Anyway, the biggest gripe I have with the above is that I had to look at 3 pages of the 56 page schematic to figure out what was going on. And I'm still left guessing because the net names do not match up :-/ Page 1 shows cpu + connector + the sheet that the CHT connects to on protect wise. Page 48 has the protect stuff, but no way of linking it up to either cpu pin or cht without seeing page 1. Page 55 has the CHT stuff, but no way of hooking it up to the protect stuff without looking at page one and guessing a bit. Hmmm. Anyway, sorted now.

Presto, add those protect bits to all of your ADC input pages, 11 bits per temp sensor, and similar for other ADC stuff, I guess.

Fred.

[Preston]

all diodes for adc protection should be schottky, not normal 1n4148 units. eg d35 in brv tab.

Done!

check d33 d34 c30, why not used? same on aap c19 d31 d32

MAP and AAP -- protection circuits arent nessasry on components internally connected with the board.

map and aap both can't exist with tabbed package. aap if installed with normal map must be tabless package.

Map is tabbed AAP is not tabbed. AAP can be selected with or without barb both non tabbed.

both map and aap can be substituted for off board map units from toyota, honda, gm, etc

If you are using off board sensors then it is suggested to install protection circuits consisting of D31, D32, C19 (AAP) and D33, D34, C30 (MAP)

no mounting for either map or aap.

MPX4250A (MAP) only comes in a tabbed package - if mounting is difficult remove tabs.

aap should have barb for routing to correct pressure zone on car.

As above optional we can make this standard if everyone agrees.

on rpm page, r212-r216 might take 1/4w but will really get that hot and should probably be taken off board into loom as trying to stand bigger packages on end on the smd pads just rips the pads off.

R212 and R216 are 0805 surface mount and 1/4 watt so should fit the current puma pad. Alternatively use fred's approach and mount in loom.

all caps that aren't tantalum should be X7R in final, not critical for spin 1, though.

Caps, up to you I have selected what will fit best with current foot prints.

fuel pump page, r66, what is that for? mine isn't populated, but it could be a good thing to have. R68/C37 should not be populated. No mods are required for d46 and r67, cept maybe the value of r67 and the part number of the d67 led. Drive fet is not included in this page and should be.

R66 = pull down, Q8 added (note in schemaitics this under general drive and not fuel) D46 and R67 up to you wont make a difference, I moved them as I felt that the fuel pump wires may obscure view of the led.

CHT stands for Cooland/Head Temperature

Cooland/Head Temperature not sure what this is? But I can change it to "Coolant/Head temperature"

CHT page, R148 should be left out (this is in the instructions that i wrote!! read them again and check the rest of your work.) why the hell would you want a zener there? lol

Done!

afaik, no zeners should be installed on the board.

Zeners replaced with Schottky's

R147 should be 1% MF as it needs to be accurate

R147 changed to 1%

all resistors should be 1% MF as they are cheap and easy to get and just better in every way

Maybe for a final version but I see it making a masive difference, except for where it counts.

CHT 3 caps listed, 2 used, one not, topology? I don't understand.

C removed as it adds no value to circuit functionality.

CHT should have two schottkys also, where are they?

Schematics are confusing at points this is one of them the protection circuit with input named "analog_sensor_in_3" shows up on three sheets, they are only distingusihed by the sheet name. Becareful! it got me. Updated bom. As seen above is ONE example (there are more which will be covered in puma-howto) that Fred has kindly beaten me to posting

All complaints about CHT for MAT and IAT too

As above, all updated.

MAT unused for foreseeable future, but good GP temp input

Noted as above.

TPS value changes not colourised.

Sure.

TPS 1n4148 must go and be replaced by schottky as above

Done.

Injector page, major hackage required whether low or high z is built. low z doesnt use fet, high doesnt use chip. recommend only high z, but marcos may have a set of hacks for low z?

Stay posted for further information to come.

Injector page, didn't check your part numbers, but assume they are good from previous discussion.

Anyone else want to double check?

Ignition, just thinking, could do it the same was as the hotel with a 100k pull up to 12v (or 5v) and the FET pulling down to ground. XOR can be used to correct polarity. Use cheap fets for this, logic level still required but load should not be significant (only the 100ohm resistor...)

Will get back to everyone on this.

Ignition should consist of cpu > 1k > xor > 1k > fet (with 100ohm pull up) (with LED setup on either output of XOR or output of FET, whatever pcb allows for)

This setup has been alowed for.

XOR resistors can be 1k to share parts. I relaxed my nazi 1.6k demands some time ago. It wasn't realistic. 1k is on my board too.

Nazi resistors replaced with civilized 1K

Power Primary Parts (PPP :-p) all red stuff seems good, didn't check non red stuff.

Anyone else want to double check?

Didn't check USB, but needs hackage to power from USB not from ECU, LEDs need hackage too as they are connected wrongly.

USB hacks incorperated, instructions to follow in puma-howto link.

Didn't check CPU clock stuff, needs checking.

Anyone else want to double check?

I think that covers it all. Thanks Fred.

Preston.