hi,
I'm designing a circuit to interface a pick-up sensor to microcontroller.
a pick-u sensor - for the people who might not know it - generates an AC voltage that is proportional to the speed of a moving metal body near the it ( the sensor ), using a magnet, i.e, it functions as a generator.
whatsoever, I used the following circuit (in the attachments) to interface it to a PIC microcontroller, as square pulses, then determining the speed depending on the number of pulses received in a predefined interval of time.
The problem is that the output is always high (5 volt), so no pulses.
any ideas ? thanks in advance ...
I'm designing a circuit to interface a pick-up sensor to microcontroller.
a pick-u sensor - for the people who might not know it - generates an AC voltage that is proportional to the speed of a moving metal body near the it ( the sensor ), using a magnet, i.e, it functions as a generator.
whatsoever, I used the following circuit (in the attachments) to interface it to a PIC microcontroller, as square pulses, then determining the speed depending on the number of pulses received in a predefined interval of time.
The problem is that the output is always high (5 volt), so no pulses.
any ideas ? thanks in advance ...