The following triac/diac based mains operated LED flasher circuit which is actually an astable multivibrator circuit utilizes only a diac and resistor arrangement for implementing interesting wig wag flashing of two LEDs.

The circuit was shared with me by Mr.Vineesh, who is one of the keen followers of this blog.

I would like to present the email that was sent to me by Mr.Vineesh.

The Circuit Objective

Dear sir,

Hope you remember me. i am not an electronics engineer,working as manager in a company, dealing basically with Tool & Die Enggr ,but self studying electronics for past 12-13 years,and have designed and made many simple projects of my own.

Some of them are marketed too.actually this entire ckt attached is not my idea.

I have gone thru 230V blinking LED circuit in some sites. i just converted it to alternate blinking. ckt working fine for last 2-3 months continuously. (used green bright leds)i know very well no need to explain the working of ckt. but just given 2 lines because if i am wrong in theory, you can correct me.

practically crkt is working well.while cap charging,led2, (series with cap) lights. DB3 get less than 30V while cap charging and does not conduct.after full charge of cap, diac conducts and led1( series to diac) lights,n cap discharge thru 1N 4007 ,that time LED2 light get dim ,which gives alternate blinking effect.

1.8K Resistor series to led1 is more than the requirement ,but given for matching the light intensity with LED2 all my ckts are drawn in note books, just selected one small ckt from that which is easy to draw in CAD & and convert pdf bcoz don't want to send shabby hand drawn drawings.

Thanks & Regards


Analyzing the Circuit

Dear Vineesh,

Your explanation is absolutely correct, and the circuit is also very good, it can be well modified for ganpati, diwali, Christmas or for other similar decoration purposes. Good effort.

Thanks and Regards



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