NE555N astable, operating point not found

Hello Mahir,

Your circuit as drawn will have a longer output high time than it will be low. This is opposite of your requirement.

To correct this, I suggest. changing R1 to 60.4k and R2 to 619k then add a diode across R2 (cathode to C2 side).

Now C2 will charge through R1 and new diode in 2 seconds while output is high and C2 will discharge  through R2 in 20 seconds while output is low.

I do not have a answer about the Tina simulation, but changing the default settings for higher accuracy or longer settling time may help.

Regards,
Ron Michallick

Dear Mr. Ron,

Thank you for your response...

I made the changes on my cct as attached, but also the same problem "operating point not found", I reached the required cct using TLC555 but still wondering about the message appear with NE555.

Hoping to solve this case.

Best Regards 

Mahir

Mahir,

Send me your NE555 TI-Tina circuit.
I will try to get it to simulate properly.

Regards,
Ron

Dear Ron,

I am not sure why I can't upload the simulation file (.TSH) to the site!!! please help me with this.

I solved this case with Mr. Marcos opinion (using voltage generator with general wave and by changing the peak values and the times) and this worked with the voltage-controlled switch, but using NE555 is important for further hardware implementation.

Also, the use of TLC555 as attached, gives the same signal, but not working with the voltage-controlled switch, and this is not obvious for me!!!! 

Hoping to receive your opinion about this.

Regrads,

Mahir

Mahir,

I ran into the same problem. I solved it by using a different tool.

Try: Analysis - Steady State Solver - MaxSearchTime = 60
This is my only solution.

Regards,
Ron