I am using TC4427A mosfet driver(having two non inverting output for two inputs) for pulsing power MOSFET .it was working fine after some time its giving constant supply voltage of 12 V even when I provide pulses.So i shifted input pulses to other input of driver ,and that is working fine for now.what will be the reason for failure /cant troubleshoot.

 

hi,
Welcome to AAC.
Do you have a circuit diagram you could post.?
E

 

THANKYOU

 

What is your opto doing?It is not connected to anything.
The TC4427 input is shown connected to 5V but I think it should be connected to the opto collector/R4 junction.
And, juts a small point, it is worth the effort to clean up the circuit diagram and have the lines straight, not all over the place like the 0V line is.
And the 240V input SHOULD NOT have a ground connected to it. I hope this was just for simulation and not real life (or death)!

Something like this, but my circuit is still a bit rough

 

opto is connected to ardiuno input which i just represented by input terminal as i did not include all of it.the opto ids driven by 5V and the output is connected to driver input.and ya that 230 V was connected to ground just for simulation.and my circuit is same as the one u drew.I was in hurry so missed it.can you tell the reason why now one input is not working

 

Do you have an oscilloscope?
If not, do an Arduino sketch to switch the opto at 2 seconds on and off, slow wnough so it can be measured with a multimeter.
First thing is to measure the 12V and 5V to make sure they are working, and are connected to the right places.
Then, measure the volts on the Arduino pin to make sure it is pulsing between 0 and 5V.
Next,R3/opto junction, 0 and 2V.
Opto collector/U2 input, 0 and 5V.
U2 output, 0 and 13V.

 

opto is working .i have checked in oscilloscope .i was using output 7 ,which is not working now.so i shifted to input 4 and output 5. I am not able figure out failure for the first output and am afraid the second one will also damage after sometime usage.

 

What is your opto doing?It is not connected to anything.
The TC4427 input is shown connected to 5V but I think it should be connected to the opto collector/R4 junction.
View attachment 149647

Have i exceeded the input current of driver by using less value of pull up resistor of 1.5k ohm.but is this datasheet of tc4427 says 10uA is max ,is it correct?anticipating positive response.thankyou

 

I think you will find that current is the load the FET driver presents to the circuit driving it. Hooking the input directly to the 5V will not hurt it, the TC4427 will draw a max on 10uA from the 5V supply.
Have you measured the power supply the TC4427 is running from, and is there good bypass caps as lose as you can get them to the chip?
It may be there are spikes on the power supply that are greater then the max volts allowable. Or the output current is too high.
I would check the supply to make sure it is good.
Have a look at....
http://ww1.microchip.com/downloads/en/AppNotes/01327A.pdf

 

Yes I had measured, it was 12V power supply as in circuit diagram(max allowable input voltage is 18V for this chip),the input is from ardiuno which outputs 5v.and yes I have used a 0.01uF ceramic capa and 10 uf electrolytic capa for bypassing and stabilizing.Anyways thankyou