DIYEFI.org Forum

Perhaps most people in the know would have already seen these, but I was on the Freescale website and saw some interesting stuff:

MC33810 - Automotive Engine Control IC - http://www.freescale.com/files/analog/d ... pdf?fpsp=1

Talks through SPI, 4 drivers for injectors and 4 pre-drivers that can be used to drive IGBTs. I am not sure, but I think it has inbuilt ion sensing when you use the pre-drivers for ignition?

MC33975 - Multiple switch detection interface - http://www.freescale.com/files/analog/d ... pdf?fpsp=1

To communicate opening and closing of upto 22 switch contacts - how about for throttle closed and WOT position, NOS, switching of multiple tables, maybe even prime the fuel pump when the driver door is opened?

Comments?

I'd seen the first one, but it doesn't have all that much balls really. Not sure about availability either.

The second one I hadn't heard of. Does it also interface through SPI ? That sounds pretty cool for sure. I like your WOT, Closed and door open prime ideas :-) MS doesn't have WOT/ Closed switch monitoring. It's not crucial, but it's definitely useful, esp for idle etc. There is a reason why many OEM TPS units are 4 pin though.

If not useful for a fully DIY version, they could definitely be useful for a miniature SMD style bike/boat/offroader version.

Thanks for sharing :-)

Admin.

Damn Fred are you on this forum 24/7 or what


How about this one instead of the 33810: MC33800

http://www.freescale.com/files/analog/d ... pdf?fpsp=1

You're right about availability though. The only thing I could find on digikey was the 33975. Its fairly cheap too.

However, these were released less than six months ago, so they could become more and more commonly available. Case-in-point: the MAP sensor used in MS was probably quite new when they designed around it, but these days its available easily and dirt-cheap for what it does too.

The 33975 talks through SPI, but one question I have is: What is the advantage? Does it leave more I/O pins free on the MCU? Or is it speed?

LOL, yeah, I'm trying to be attentive :-) If I can keep on top of everything, then hooray. How long that will last though I don't know. Last night I got to bed 330am, night before 4am, one before that 5am. It's not sustainable though.

I think people underestimate just how much I care about this :-)

The only advantage of any of them is pin count really. They can probably handle more current too though.

I would like to KISS for now. With 90 pins, a typical 4, 6, or 8 cylinder application with COP should still have plenty of spare IO for virtually anything you want to do. The only thing it might be a bit lacking for is SERIOUS data logging for track use, but even for that it should have enough for most high end novices like me :-) There should be around 10 spare ADC channels and heaps of digital IO and PWM etc. I think using external chips is probably overkill at this stage, but it is certainly good to bare them in mind while working on it :-)

Thanks again,

Admin.