Hi landspeed and all,
It was a little tough mission to interface the pulse width modulation injector signal for his low-impedance injectors.
http://www.acceleronics.com/faq.htm#2
The SuperMID is designed for a standard high-impedance injectors which drive pulse is simple single pulse.
We had two approaches to filter his injector pulses...
A: analog CR (capacitor and resistor) filter
B: digital microprocessor controlled filter
He tried the approach-A, but no good result.
I tried the approach-B and it worked.
Please refer to attached chart.
The top green signal is the original output from ECU.
The middle red signal is after voltage shift(12V->5V) for filter input.
The microprocessor watches the pulse state change and counts 0.8 msec timer.
If the pulse state did not change in 0.8 msec, the pulse is good, then output change to meet the input.
If the pulse state changed but it was shorter than 0.8 msec, the pulse is ignored.
(The actual microprocessor has jumper setting to change the ignore period, 0.2 to 0.8 msec.)
So, the SuperMID M-1 is now working with such low-impedance injectors.
Regards,
Yoshi
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