The NE555 timer IC is a 8 pin dip package IC which performs variety of timing tasks in the electronic circuits. There is a huge list of 555 IC circuits or projects due to which it is very popular among electronics hobbiests. So here is a project of a 555 tester circuit which is very useful to check 555 timer
ICs. In this circuit the NE555 IC is wired as an astable multivibrator and when power is applied the LEDs will start flashing which will show that the IC is working. The flashing rate of LEDs can be controlled by increasing or decreasing the values of 69K and 40K resistors.