1. I have a encoder, which has A,B & Z output. It is 12V powered. Datasheet says encoder can go upto 300Khz at full speed.
To work with microcontroller(3.3V) but encoder is 12V so I have added a 1000hm series resistor & 3.3V zener diode. Only used A & Z, didn't use B in my circuit.
2. Now I have to detect when rising edge of Z when it comes. But problem is there is random noise comes, which gives false interrupt to microcontroller. The wire length between microcontroller & encoder is around 90cm. I think this could be the problem. However this is case of Z output only, in output A I don't have this problem. it don't give any problem.
3. Attached is pd f. Page 1 shows that I rotate motor at maximum speed, the correct output which I need to detect. Page2 & 3 the noise which cause false trigger to MCU. Page 4 shows correct output at lesser speed.
4. How to remove this noise & correctly detect the rising edge. I had placed 0.01uf or 0.1uF also, but in that case correct waveform never appears. Always noisy waveform appears?
5. Currently I have placed 1000ohm & 3.3V zener , what is the correct way to reduce 12V at such high speed?
To work with microcontroller(3.3V) but encoder is 12V so I have added a 1000hm series resistor & 3.3V zener diode. Only used A & Z, didn't use B in my circuit.
2. Now I have to detect when rising edge of Z when it comes. But problem is there is random noise comes, which gives false interrupt to microcontroller. The wire length between microcontroller & encoder is around 90cm. I think this could be the problem. However this is case of Z output only, in output A I don't have this problem. it don't give any problem.
3. Attached is pd f. Page 1 shows that I rotate motor at maximum speed, the correct output which I need to detect. Page2 & 3 the noise which cause false trigger to MCU. Page 4 shows correct output at lesser speed.
4. How to remove this noise & correctly detect the rising edge. I had placed 0.01uf or 0.1uF also, but in that case correct waveform never appears. Always noisy waveform appears?
5. Currently I have placed 1000ohm & 3.3V zener , what is the correct way to reduce 12V at such high speed?
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