# Simulation behaves differently in Proteus vs Icircuit

I'm an electrical engineer student and I'm trying to make an LED Flasher circuit using a 555 Timer.

When I simulated the circuit in Proteus simulator, it's not working! But in Icircuit simulator it works perfectly! It's an identical circuit.

The question is: Why is the circuit not working in Proteus?

Circuit in Icircuit:

Circuit in Proteus:

• The polarity of TRIG and R seem to be opposite between the two. – Eugene Sh. Jul 26 '19 at 15:01
• Check the models. – Andy aka Jul 26 '19 at 18:09
• I imagine you have ALL the signals available to you. Post some traces from Threshold, Trigger, and Q, and let's see if we can figure it out. – Scott Seidman Jul 26 '19 at 18:35