Robert's 0.6-alpha Jaguar Build

[DeuceEFI]

Jaguar 0.6-alpha Assembly Guide located here: viewtopic.php?p=36648#p36648

[E4ODnut]

Now, as I understand it, The existing ignition signal design is for either GM DIS or Ford EDIS. Both of which I believe are VR signals, hence the MAX9926UAEE chip. Can I use this at all for TFI PIP input, or do I have to build a circuit to input a signal that is acceptable?

As for ignition output, it looks to me like the igniter outputs circuit should be able to create a signal to the TFI SPOUT, but I'm not sure exactly how.

As for the configuration of injector drivers, what should I use for two banks of 3 Hi Z?

[Fred]

Robert, neither DIS nor EDIS present the VR signal to the ECU, just a hall/opto/logic-level signal similar to your TFI setup. Follow the provided instructions configuring the MAX chip for Hall use as described.

The ignitor output drivers can indeed create your signal.

What is the DC resistance of each High-Z injector in your engine? If it's 10 to 15 ohms you can just attach 3 of them to one FET. Use pins T6 and T7 to control those two FETs.

Fred.

[E4ODnut]

Fred,
Thanks.

If you recall from the TFI documentation, the Profile Ignition Pickup signal is 12 volt square wave. Are you sure I can configure the MAX for this?

If so then I should be able to configure one channel of the MAX chip for Hall Effect crank position (PIP) signal, and the other for VR Vehicle Speed Signal input. From a firmware perspective, does it make any difference to you which is which?

There are three different igniter drivers available for use depending on the type of output required. I'm not clear on which one I need. I have the TC4227AEOA (two non-inverting drivers) but it's no big deal to get the right ones if these won't work for my SPOUT signal.

Ford spec for injector resistance is between 13.0 and 16.0 ohms each. In my configuration the bank resistance should be between 3.25 and 5.33 ohms.

[Fred]

If the PIP signal is a raw signal that is autonomous and does not need a pull up, simply do not install a pull up or that voltage will feed into the 5V rail slightly (not a huge deal, but...). The negative input requires setting at a threshold point, typically 2.5V even if your signal is higher. So simply do not install one pull up resistor and follow Hall instructions for the rest.

Do not build the second input yet. No VSS for you, yet. Testers, not users. Get up and running in the most basic form first. Get everything how you like it later. Please. Anything else is going to waste countless hours of time I don't have. Your PIP should be on RPM0+, leave RPM1 unconfigured for the time being.

I believe you need a high pulse, so you have the correct ignitor chip, just install the 12V jumper for it if you want/need a 12v pulse, or 5v if you need/want that.

Your injectors could all be driven by a single FET, so it's totally fine to drive two sets of 3 with two FETs.

We'll be face to face in a few days, so focus on all of the standard parts of the build, and bring the parts and board and whatever else you want/need with you, maybe we can finish it off together :-)

Fred.

[E4ODnut]

OK. Thanks Fred

[E4ODnut]

I had a look at the data sheet for the MAX9926 and it looks to me like the maximum input voltage is VCC (5 volts). Am I missing something here?

[Fred]

Yes, you're missing a lot. :-)

[E4ODnut]

Thanks for the detailed explanation.

[Fred]

You're welcome! :-p LOL, VCC is the power feed pin. Your signals go into the inputs, not the power rail.