555, The low cost timer IC that widely used as commercial timer ic. 555 is also popular to the students, electronics hobbyists for its simple interface and cheap rate.
Here the 555 timer & its pin out,
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| 555 |
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| internal diagram of 555 |
Pins:
- Ground : Connected to the 0V.
- Trigger : Detects 1/3 of rail voltage to make output HIGH
- Output : Result output
- Reset: To reset must be taken under .8V
- Control :To vary timing of RC network
- Threshold : Detects 2/3 of rail voltage to make output LOW
- Discharge : Discharge
- VCC : Connected to the supply
