Hi,

What happens if the circuit is run without a load, how can I protect the mosfets, my output current is 2A duty 97% Freq 2HZ

 

97% on for Q1?
2hz is a long time!
The energy to keep Q1 on is stored in C1, C2. R3 is discharging C1. Make R3 as large as you have. (1meg or more)
I have not done the math but R3 * C1 time constant needs to be 1 second or more. There there is current to run the IC and that is in the data sheet.

I have a circuit like this where I keep Q1 or for hours. I removed D1 and added this power supply. It lives on +12V and makes a isolated 12V to turn on Q1.

Input voltage options are 5V, 12V 15, 24 .....
Output options are 3, 5, 12, 15, 24
1W and 2W
-------------------------
Circuit should be OK with no load.

 

97% on for Q1?
2hz is a long time!
The energy to keep Q1 on is stored in C1, C2. R3 is discharging C1. Make R3 as large as you have. (1meg or more)
I have not done the math but R3 * C1 time constant needs to be 1 second or more. There there is current to run the IC and that is in the data sheet.

I have a circuit like this where I keep Q1 or for hours. I removed D1 and added this power supply. It lives on +12V and makes a isolated 12V to turn on Q1.
View attachment 253455
Input voltage options are 5V, 12V 15, 24 .....
Output options are 3, 5, 12, 15, 24
1W and 2W
-------------------------
Circuit should be OK with no load.

What should my R3 C1 value be for 2 hz? what is the math?

I don't understand if the mosfets will be damaged under no load, what do I need to change?

My frequency is 2 Hz but Q1 on time should be 500 uS How should my HIN and LIN timing be?