I have a Inductive sensor wich depending on speed changes the resistance is this right?
Wich simple, small circuit do i need to make the alternating singnal go digital? sow the microcontroller can measure the pulses?
I tried to make it work with a transistor but looks like when putting 0,4 volts on the gate there are 0,5 on the pic.
When i adjust the 2nd adjustable resistor wich is in series with the sensor.
Then the voltage on the input pin increases
Sow my situation is: How to make
an smitt trigger input, or how to convert some analog signals to digital ones?? am i done when i use the ST (smitt trigger) inputs my pic cpu has???
What i have tried is to Put the sensor in series with a pot.
I calculated that the value from the pot should be 7500ohms, because my sensor gives 1000ohm in rest, 1100 when slowturning anyway its difficult to measure.
I wouldn't have thought so?. Inductive sensors are usually just a coil that detects a magnet passing by it, just like a dynamo or alternator. So the output is a sinewave, the frequency of which varies with the speed of rotation.
Wich simple, small circuit do i need to make the alternating singnal go digital? sow the microcontroller can measure the pulses?
I tried to make it work with a transistor but looks like when putting 0,4 volts on the gate there are 0,5 on the pic.
When i adjust the 2nd adjustable resistor wich is in series with the sensor.
Then the voltage on the input pin increases
Sow my situation is: How to make
an smitt trigger input, or how to convert some analog signals to digital ones?? am i done when i use the ST (smitt trigger) inputs my pic cpu has???
What i have tried is to Put the sensor in series with a pot.
I calculated that the value from the pot should be 7500ohms, because my sensor gives 1000ohm in rest, 1100 when slowturning anyway its difficult to measure.
That sounds completely wrong!. First you need to determine if your sensor has internal electronics, does it have power to it?. If so, you then need to use a scope on the output to see what the signal is like - if it's a decent size sinewave then a simple schmitt trigger is all you need. Or you could even just feed it through a resistor to the base of an unbiased transistor?.
Do i still need to connect the input pin to GND with 10K resistor?
even if i use the ST inputs??
1K is that enough to connect the base to the Emitter?
Sow if i have the 2 wires from the coil,
i put 2 diodes on it? or what do i do with that part?
Then the voltage coming out of it will be DC, then i put a 1K From the base to the emitter(???? not collector???) , and from the emitter to the input pin??
I cant untherstand wy to the emitter and not to the collector?
BC547 is that the one i need???(NPN)
Maybe i will just try hooking it up directly, the currents will be made smaller by an resistance...
Could it work??
I have to put an resistor because i imagine on high turning speeds the voltage could rise high right??
Do i still need to connect the input pin to GND with 10K resistor?
even if i use the ST inputs??
1K is that enough to connect the base to the Emitter?
Sow if i have the 2 wires from the coil,
i put 2 diodes on it? or what do i do with that part?
Then the voltage coming out of it will be DC, then i put a 1K From the base to the emitter(???? not collector???) , and from the emitter to the input pin??
I cant untherstand wy to the emitter and not to the collector?
BC547 is that the one i need???(NPN)
Maybe i will just try hooking it up directly, the currents will be made smaller by an resistance...
Could it work??
I have to put an resistor because i imagine on high turning speeds the voltage could rise high right??
With an inductive trigger sensor for the cars engine, I use a LM1815 to read it. I don't think this helps you though, without knowing more about your ABS sensor.
It's odd that this is a straight inductive sensor. Usually ABS wheel sensors give a square wave signal.
the upper bar you see is in the coil and its a permanent magnet, i think that the pulse coming from the coil is to short to be noticed by the multimeter.
the abs ring has allot of teeth and there are also very small sow think that is the problem for the multimeter.
i could smell that solution, but i ask it to know how i could do it??
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With an amplifier - sorry, but it's true! - either use an opamp or a discrete amplifier. But again, you need to know what's coming out of the sensor, you can't get anywhere completely blind!.
I have tried to connect a led to the sensor but it doesn't light up..