Simple Tester For IC 555

Timer IC 555 multipurpose has habit to emerge in so many various wide circuits. Because of this is very useful small components, hence this component becomes very popular in the last few years. Though IC 555 in general hardly relied on, but sometimes happened also error. Circuit designed here will give way of simple and effective to do assaying of damage component. The timer which wish to be tested ( 555), connected as multivibrators is unstable (free running). If nipple SW1 is depressed closed, hence condenser C1 will start loaded [by] through preventive reactor R1 and R2. Soon after strain level at this condenser reach point of timer launch, hence internal of flip-flop will be moved and pin 7 is degraded its the strain to empty C1.
Reset flip-flop when strain C1 reachs threshold level IC. This thing causes boosts pin 7 and impregnation cycle starts again. Output timer (pin3) attributed to a couple of LED. If high output of LED D2 will on and D1 will turn off. On the contrary, when low output of D1 will on and D2 is off. LED will wink if IC in good condition.

For reader having other application and wish to change its (the frequency, hence speed of LED is determined the value by value from R1, R2, and C1. Frequency countable oscillation passed formula:

If R2 far bigger than R1, hence its the frequency can be estimated from formula following:

Value to showed in circuit, oscillation frequency around 0,5 Hz. Test device can be designed considerably compact with soldering all components directly at test collar IC, firstly is attached through aperture at hole surface of box device which will be used. In rotation, all components can be attached at as of slab PCB. Usage of current a minimum and can be supplied from a battery 9V.