problem with IR2110 and DC/AC converter portion of sine wave inverter

I'm trying to design a sine wave inverter based on Switch Mode technology. I tried many circuits. each of them creating problem. now the latest one was like this:



Mosfets are protected via that fuse from burning. I am using 1A fuse there. Fuse is burning again and again. I don't know why. I fetched this same problem before but found no solution.

MCU pic16f73 is generating two PWM signals like:


what is the problem and what is the solution?


again I tried with another one. But in that circuit NE556 is not generating any clock pulses. I checked PCB diagram again and again, but still can't find then ans. But the DC/DC converter portion is working fine.

the circuit is:


and my DC/AC converter portion is:



Now the question is why all these faults happening???

The circuit of 556 has a input from 315V but it is only connected to ground. This is a apparent fault in circuit diagram, there may be others. Can you show circuit diagram of inverter using MCU pic16f73?

that +315V is connected to pin 12&13 of NE556 via 1M+470K+470K||(500KVR+33K). and the circuit diagram of the inverter with PIC16f73 is the first one post.


My question is what is the frequency in first stage DC/DC converter (with KA3525) ? and then what should be the intial frequency of PWM to generate 50Hz sine wave in the next stage?????

I dont see circuit diagram of 1st inverter. Its only the PCB design. Frequncy is determined by Rt on pin 6 and Ct on pin 5 of 3525 ic. Here it is 39k(R7) and 1n (C5) are shown.It will be around 35KHz.

No, Its 22KHz.