I have made a full-bridge inverter using the IR2110 IC. The MOSFETs used are IRF540n. The bootstrap capacitor is 4.7uf. The diodes used are 1N5819 high-frequency Schottky diodes. The operating frequency is 50KHz. The input signal is given using an Arduino Uno. 1.5kohm gate to source resistor is also connected. The pictures of the inverter are shown below.



The power to both ICs is given using a single isolated 12V power supply. The 5V signal is also given using the same supply with the help of the LM7805 regulator. The picture is shown below.




The input DC signal is given from the DC supply of 31V. The output is taken across a 5Kohm 10W resistor. The issue is that the output signal is not consistent. The signal comes for some periods of time. The output signal picture is shown below.






The areas in which the output is coming is absolutely correct. But overall it is not coming. The ICs are tested they are working fine.





Can anybody tell what can be the issue? Is the 5v and 12v signal must be given from separate isolated supplies or that is not the problem. This is the schematic diagram.




Regards

 

Where is your VDD, pin #9?
Max.

 

The power to both ICs is given using a single isolated 12V power supply. The 5V signal is also given using the same supply with the help of the LM7805 regulator

I see no isolated ground no opto couplers& or isolation transformers.

 

I see no isolated ground no opto couplers& or isolation transformers.

I have used an isolated power supply with an isolation transformer from which I am powering both the ICs.

 

I have used an isolated power supply with an isolation transformer from which I am powering both the ICs.
View attachment 232897

however, the ground of both ICs is same.

 

Where is your VDD, pin #9?
Max.

The VDD pin is connected to 5volts with the same isolated power supply of 12volts using a 7805 regulator. In proteus simulation, however, pin 9 is hidden.

 

Did you use a calculator for the bootstrap capacitor?
https://www.silabs.com/support/isolation-bootstrap-calculator

 

Did you use a calculator for the bootstrap capacitor?
https://www.silabs.com/support/isolation-bootstrap-calculator

No, I did not use a calculator. But I have read some resources about bootstrap calculation for IR2110 and there I found for frequencies of 30kHz to 50kHz, bootstrap capacitor value should be between 22µF to 4.7uF.

One of the link is: http://tahmidmc.blogspot.com/2013/01/using-high-low-side-driver-ir2110-with.html

 

I have used the Tahmid link in the past, However I believe also the 1.5k gate resistor is redundant as the output is a totem pole output.

 

I have used the Tahmid link in the past, However I believe also the 1.5k gate resistor is redundant as the output is a totem pole output.

So what are your opinions on the links, do they work.

 

The reason he used the gate to source resistor was he lost some Mosfets at power up, until the resistors were implemented, I suppose the moral is, if not sure, use them.

 

Your schematic shows Hin (left) connected to both Hin (right) and Lin (right). Presumably a typo?

 

Your schematic shows Hin (left) connected to both Hin (right) and Lin (right). Presumably a typo?

No, Wires are overlapped. Hin of first IC is connected to Lin of second and vice versa. Sorry for the confusion.

 

Looks more like either a bad connection on one of your mosfets or just a bad/dead mosfet.

 

Looks more like either a bad connection on one of your mosfets or just a bad/dead mosfet.

I have checked each MOSFET before connecting it to the circuit also checked the connectivity of each connection. However, I will check that again. Thanks for your suggestion.