Originally posted by Billman
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BTW what would be approx the price for this conversion board?
The board will be pretty cheap to make, it's the engineering involved that's difficult and the MAF sensor from Bosch + housing will be also about 100 EUR.
I am not an electrical engineer, so even simple things like reverse current protection are difficult for me, because there are many options and I don't know which to pick
For example reverse protection on the 0-5V signal from the MAF, would probably be a diode with a fuse or a MOSFET.
Reverse protection on the +12V feed could be just a series diode, etc...
Basically I have the following inputs:
+12V - connected to the car
GND - ECU ground
0-5V - Signal from HFM5
And the following outputs:
+5V reference for HFM5
0-6V - Conditioned signal to ECU
Considering this thing will be possibly installed by people who can mess things up (sorry ), I need to make sure that if things accidentally are connected the wrong way around, the board does not melt.
The ones that are connected by people, will be +12V, GND, ECU signal. So at the very minimum, there needs to be reverse voltage protection on +12V/GND, short circuit and reverse voltage protection on the ECU signal.
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