Circuit Splash

Bistable Multivibrator mode of 555 timer IC is the easiest mode of 555 timer IC, where Monostable multibrator mode has one stable & one unstable state, Astable multvibrator mode has both the unstable states, here in Bistable mode, both the states are stable

Darkness detector is simply a LDR (Light Dependent Resistor) interfaced square wave generator. In this project the square wave generator is developed as a 555 Timer IC based ASTABLE MULTIVIBRATOR. Before going any further we must get the basic details on the LDR. The figure below shows an image of various types of LDR.

When the 555 IC is used to produce an MONOSTABLE circuit - it will only pulse once. Monostable circuits can be used to turn lights/LEDs on or off just once. They are also used in many more school based circuits.

In this article, you will learn how to improve your collection of Snap Circuits blocks by adding a 555 Timer IC. You will learn the functions the pins on the 555 chip. You will learn that when the 555 is in astable mode, the output of pin 3 is a continuous stream of pulses called a square wave that can be heard on a speaker as a tone.

In this Instructable, I first demonstrate how to build the complete circuit on a breadboard using two NPN transistors and two LEDs. Once that circuit is built, I demonstrate how we can break the circuit out onto a circuit we will draw with your CircuitScribe pen!

This is done by connecting the OUTPUT of each timer to the TRIGGER of the other through a diode and placing a resistor in the trigger circuit. The resistor limits the current from the opposite timers output when the trigger is closed on the stopped timer.

As the name suggest 555 timer is basically a “Timer”, which create a oscillating pulse. Means for some time output pin 3 is HIGH and for some time it remains LOW, that will create a oscillating output.

Bust out that 555 timer and use it to build your own AM radio transmitter. The circuit that is using only needs the timer chip, an NPN transistor, three caps, three resistors, and a potentiometer. It generates an amplitude modulation signal around the 600 kHz range which you will be able to pick up with any normal AM radio.

IC CD4017 is a CMOS decade counter IC. It can produce output at the 10 pins sequentially, i.e. it produce output one by one at the 10 output pins. Explore below some interesting electronic circuits based on IC CD4017.