hello gorky.
i got the China maf, it's in fact made in china, with words on the cover showing that.
i de-potted the PCB inside. easy.
i have rev. engineered , the first phase, photos and page to follow soon. its a 8v Pic micro processor inside, 8pin SMD > 12F683
the bad news is the crappy 5v power regulator used,
they connected the 78L05 regulator to 12vdc pin via a series diode and small cap to ground, very poor protection for the 78L
max input to 78L is 30v max, the cars electrics can do 100v easy during load dumps, and jump starting car battery.
it has minus spike protection but not plus spike and that is not good.
there is an adjustment variable resistor ,inside too, but was potted over. (the potting was some kind of weak rubber coating that peeled right off)
the hot wire is good,as is the temperature thermistor.
im doing some more live tests tomorrow
the board inside was never de'fluxed, i'd bet, hand soldered too...
the board is 3 layer board.
i wonder do any of these china made MAF's ever work? right?
cheers for now.
i got the China maf, it's in fact made in china, with words on the cover showing that.
i de-potted the PCB inside. easy.
i have rev. engineered , the first phase, photos and page to follow soon. its a 8v Pic micro processor inside, 8pin SMD > 12F683
the bad news is the crappy 5v power regulator used,
they connected the 78L05 regulator to 12vdc pin via a series diode and small cap to ground, very poor protection for the 78L
max input to 78L is 30v max, the cars electrics can do 100v easy during load dumps, and jump starting car battery.
it has minus spike protection but not plus spike and that is not good.
there is an adjustment variable resistor ,inside too, but was potted over. (the potting was some kind of weak rubber coating that peeled right off)
the hot wire is good,as is the temperature thermistor.
im doing some more live tests tomorrow
the board inside was never de'fluxed, i'd bet, hand soldered too...
the board is 3 layer board.
i wonder do any of these china made MAF's ever work? right?
cheers for now.
![[Image: china-pcb2.jpg]](http://www.fixkick.com/sensors/china-maf/china-pcb2.jpg)
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