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I want to be able to use 555 timers. I found a tutorial on how they operate, and a basic circuit for each type (monostable, astable, bistable). This is the circuit for the monostable. I followed the diagram, connected all the pins where they are said to be connected, and used all the values for everything in the instructions.
You should be able to push the switch, (switching the trigger pin to low). Then the LED should light for 5.17 seconds based on the values for the capacitor and the resistor.
Instead. Nothing happens. I notice that when the switch is pushed, the voltage at the LED goes high, and then goes negative (the opposite of what is supposed to happen). I tried reversing the Vcc polarity, and increasing the voltage to 100V. The light comes on, but only if you’re holding the switch.
What is wrong with this circuit?
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