So I've got a schematic/diagram for an Ambient-Light-Ignoring Active Motion Detector.
It has 1 LM555, so it's a timer... but how do I actually set the timer? I know how to do it in PLC programming but how to set it when its on a circuit board or?
I'm a second year bachelor student in mechatronical engineering and we have just learned about operational amplifiers in electronics. But I want to know moaaaa
It has 1 LM555, so it's a timer... but how do I actually set the timer? I know how to do it in PLC programming but how to set it when its on a circuit board or?
I'm a second year bachelor student in mechatronical engineering and we have just learned about operational amplifiers in electronics. But I want to know moaaaa
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Is this the circuit?
http://transducercircuit.blogspot.com/20…
If so, the 555 is being used as an oscillator to generate a drive signal for the LED, so you don't "set" it, it just oscillates.
The 555 is a pretty simple device. You can find a block diagram of it on its data sheet. To understand how it works you need to know about comparators, logic gates, flip-flops and voltage dividers.
http://transducercircuit.blogspot.com/20…
If so, the 555 is being used as an oscillator to generate a drive signal for the LED, so you don't "set" it, it just oscillates.
The 555 is a pretty simple device. You can find a block diagram of it on its data sheet. To understand how it works you need to know about comparators, logic gates, flip-flops and voltage dividers.
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555 timer is set by the voltage on the threshold pin. Commonly there would be a capacitor charged through a resistor from the supply. When the voltage on the pin is 1/3 supply then the 555 output is on.
Change timing by altering the resistor and/or the capacitor
Change timing by altering the resistor and/or the capacitor