Automatic LED Flashing Circuit using NE555 Timer IC Projects

Automatic LED Flashing Circuit Projects

Figure-1

This is a reliable timer NE555 IC(Integrated Circuit) that can be used for several circuits such as frequency divider, pulse width modulator, linear ramp generator, missing pulse detector, waveform generator, voltage controlled oscillator(VCO), FSK(Frequency Shift Keying) generator Fingerprint Biometrics,ris Biometrics, RFID Reader etc. Here we will illustrate another application which is Automatic LED Flashing Circuit using NE555 Timer IC Projects. Here is one NE555 timer-based circuit for you – An LED Flasher Circuit Diagram. So here is the step-by-step guide to make this Automatic flashing LED circuit.

Circuit Components

1. 9-12volt Battery-01 psc [See Buy Click Amazon]
2. NE555 Timer-01 psc [See Buy Click Amazon]
3. 10uf,25volt polarized capacitor-01 psc [See Buy Click Amazon]
4. 1k ohm Resisto-02 psc [See Buy Click Amazon]
5. 470 ohm Resistor -01 psc [See Buy Click Amazon]
6. 3mm LED-01 psc [See Buy Click Amazon]

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Working of the Circuit :

following the Step By Step

• First time collect all the required components.
• Connect pin 1 of the NE555 timer IC to the ground. show Figure-1
• Connect pin 8 of NE555 timer IC to Vcc(9VDC). show Figure-1
• Connect pin 8 and pin 4 of the NE555 timer IC.
• Connect pin 8 with pin 7 using a R1 resistor.
• Connect pin 6 with pin 7 using a R2 resistor.
• Connect pin 2 and pin 6 of NE555 timer IC.
• Connect pin 2 to the positive terminal of the capacitor. and another the terminal connects to the Ground.
• Connect pin 3 which is the output pin with the positive lead of LED using a 1kΩ resistor. The negative lead of LED needs to be connected to the ground.
• Connect the power supply in the circuit.
• when you connect the power supply to the circuit, it flashes the LED.
• If that doesn't work, check the connections again. Also, make sure the battery is properly connected to the circuit and power is reaching the circuit components.
• If you want to add more LEDs to this flashing LED circuit, connect them parallel with the first LED using proper resistors.

NE555 Timer IC(Integrated Circuit)

These devices are precision timing circuits capable of producing accurate time delays or oscillations. In the time-delay or mono-stable mode of operation, the timed interval is controlled by a single external resistor and capacitor network. In the a-stable mode of operation, the frequency and duty cycle can be controlled independently with two external resistors and a single external capacitor.

The threshold and trigger levels normally are two-thirds and one-third, respectively, of  VCC. These levels can be altered by use of the control-voltage terminal. When the trigger input falls below the trigger level, the flip-flop is set, and the output goes high. If the trigger input is above the trigger level and the threshold input is above the threshold level, the flip flop is reset and the output is low.

The reset (RESET) input can override all other inputs and can be used to initiate a new timing cycle. When RESET goes low, the flip-flop is reset, and the output goes low. When the output is low, a low-impedance path is provided between discharge (DISCH) and ground.

The output circuit is capable of sinking or sourcing current up to 200 mA. Operation is specified for supplies of 5 V to 15 V. With a 5-V supply, output levels are compatible with TTL inputs.

Simplified Schematic

Pin Configuration

Pin Functions

PIN No	PIN Name	DESCRIPTION
Pin-1	GND	Ground reference voltage
pin-2	Trigger	Responsible for the transition of the flip-flop from set to reset. The output of the timer depends on the amplitude of the external trigger pulse applied to this pin. Start of timing input. TRIG < ½ CONT sets output high and discharge open
pin-3	Output	Output-driven waveform and High current timer output signal.
pin-4	Reset	A negative pulse was applied to this pin to disable or reset the timer. When not used for reset purposes, it should be connected to VCC to avoid false triggering. Active low reset input forces output and discharge low.
pin-5	Control Voltage	Controls the threshold and trigger levels. It determines the pulse width of the waveform. An external voltage applied to this pin can also be used to modulate the output waveform. Controls comparator thresholds, Outputs 2/3 VCC, allows bypass capacitor connection.
pin-6	Threshold	Compares the voltage applied to the terminal with a reference voltage of 2/3 Vcc. The amplitude of the voltage applied to this terminal is responsible for the set state of the flip-flop. End of timing input. THREE > CONT sets output low and discharge low
pin-7	Discharge	Open collector output which discharges a capacitor between intervals (in phase with output). It toggles the output from high to low when the voltage reaches 2/3 of the supply voltage. Open collector output to discharge timing capacitor
Pin-8	Vcc	Supply voltage concerning GND. Input supply voltage, 4.5 V to 16 V. (NE555 maximum is 18 V)

Frequently Asked Questions:

What is the NE555 timer IC?

It functions as a square-wave structure generator with an obligation cycle differing from half to 100 percent, Oscillator, and can likewise give time postpone in circuits. The NE555 timer got its name from the three 5k ohm resistors associated with a voltage divider.

How many types of NE555 timer IC?

1. Psycho-stable
2. Stable
3. Bi-stable