Two Auto-ON Delay Timer Circuits || 555 IC or Transistor
by Molted in Circuits > Electronics
3377 Views, 0 Favorites, 0 Comments
Two Auto-ON Delay Timer Circuits || 555 IC or Transistor

This Timer circuit remains OFF when connection is given and turns ON automatically after few seconds, depending on the value of Capacitor used in the circuit.
Here, I will show you two different ways to make this circuit using :
1. 555 Timer IC
2. Transistor
Pushing the push button switch turns OFF the output (LED), which then turns ON automatically after few seconds, influenced by the capacitance used.
Components Required


These are the Components Required for making the circuit:
1. Using 555 Timer IC
• 555 Timer IC
• Momentary Switch
• Resistors: 47 K Ω, 330 Ω
• Capacitor: 100 μF
• LED
2. Using Transistor
• Transistors: BC 547
• Momentary Switch
• Resistors: 1M, 330Ω
• Capacitor: 100 μF
• LED
Other Requirements :
• Battery: 9V and battery clip
• Breadboard
• Breadboard Connectors
Circuit Diagrams


These are the Circuit Diagrams for making the circuit using :
- 555 Timer IC
- Transistor
Step-by-Step Tutorial

This video shows step-by-step, how to build all these circuits.