The OUT-output of the NE555 is on pin 3. It can only take up two states...
![]() Internal circuit diagram OUT-output of the NE555. |
In the circuit you use two LEDs (LED1 and LED2), to indicate the state of the output...
When you connect the battery and start to use circuit, the NE555 is always in the state OUT = LOW (LED1 is on).
![]() Circuit diagram OUT output of the NE555. |
![]() Circuit OUT output of the NE555. (Enlarge) |
Internally the output uses a separate output stage. This allows the output (OUT) to be loaded with up to 200 mA.
In the next step you change the state of the output.