Home     Contact     Projects     Experiments     Circuits     Theory     BLOG     PIC Tutorials     Time for Science     RSS     Terms of services     Privacy policy  
 Home      Projects     Experiments     Circuits     Theory     BLOG     PIC Tutorials     Time for Science   

<< Back to INDEX

555 Timer IC Testing Simple Circuit [Project]
posted March 13 2014 4:05.36 by spic0m

This simple 555 IC testing-circuit tests your entire 555 timer IC, so before using your IC check immediately that your IC is good or bad by checking it. This can be done by checking the IC that is it is oscillating or not. Or you can use this circuit in some other circuits also to troubleshoot the proper working of 555 IC.

This tester will rapidly tell you if the timer is functional or not. Important feature of this circuit is it will tell 555 timer is shorted or it is not oscillating. Assemble the circuit properly as shown in circuit diagram.

First of all insert the IC in socket very carefully so that no pin of 555 timer get damage. Now to see the result, switch on the power supply. If your 555 timer is working properly, both the LED1 and LED2 will glow. And any of the LEDs is off or both LED1 and LED2 are not glowing means your 555 timer IC is faulty.

In this circuit, the NE555 IC is used as an astable multivibrator and when power is provided to circuit, the LEDs will start blinking which will show that the IC is working. The blinking rate of LEDs can be changed by increasing or decreasing the values of resistor R1 and R2 and capacitor C1.

You can calculate the time duration with the help of formula given below:

T = 0.7(R1+2R2)*C1 in seconds.

As soon as power supply is provided, C1 will start charging through R1and R2.When the voltage across C1 rises above 2/ 3 of supply voltage, the internal Flip Flop toggles. As a result, pin 7 becomes low and C1 starts discharging. When the voltage across C1 goes below 1/ 3 of supply voltage, the internal Flip Flop resets and pin 7 goes high. The C1 again starts charging. All this will happen only when your IC is in good condition. According to the frequency as set with the help of resistor R1, R2 and capacitor C1 charging and discharging take place and LED1 and LED2 will flash accordingly. From these observations, we can conclude that IC NE555 is faulty or not.

[Link: Electronics Hub]

You might also like...

5A 30W Dummy Load [Project]

Solder Paste Dispenser [Project]

The Perfect Safe will keep Kids Busy! [Project]

Toilet Paper Dispenser now offers Squarely Folded Piling [Project]

Dr Brown's capacitor ESR tester [Project]

How to «open» microchip and what's inside? [DIY]

A Website-Down-Alarm lets you know the bad news first

LED Resistor Dial Selector [Tools]

<< Back to INDEX



  Email (shall not be published)


Notify me of new posts via email

Write your comments below:
BEFORE you post a comment:You are welcome to comment for corrections and suggestions on this page. But if you have questions please use the forum instead to post it. Thank you.


No comment yet...

Be the first to comment on this page!

 Contact     Forum     Projects     Experiments     Circuits     Theory     BLOG     PIC Tutorials     Time for Science     RSS   

Site design: Giorgos Lazaridis
© Copyright 2008
Please read the Terms of services and the Privacy policy