| ??? 02/27/08 10:37 Read: times |
#151514 - Resistor Responding to: ???'s previous message |
Of course if you need an RC filter you should keep the resistor and add a capacitance before uC pin. Anyway you can find a great number of suitable values for the RC circuit. Keep the R as small as possible and increase the capacitor value. Use basic RC electronics formulas to find the appropriate values. A filtering system also could be done using software Currently i don't know because you want to filter an encoder output. Normally 100nF close to the pin is sufficent to remove field noises and glitches. Of course you have to consider cable length between the encoder and the processor. William Erik Malund said:
You can completely remove your 100kOhm from the circuit ... or ...
if you want you can keep a very small resistor 100 ohm for example. The senson is a NPN open collector system so it can drive current only in one-way. I would not remove the resistor, just reduce the value and add a small capoacitance on the uC input. "speed sensor" usuallu means motor "motor" usually means (elctrical) noise. Erik |
