Need help on proper circuit connection

[Tahsinhossain]

I am trying to test IGBT switching using the following circuit but the IGBT smoked out. I am using MSP430 with g2553 chip, NMK0505SAC dc-dc converter, FOD3184 optocoupler and IRG4BC20UD. Please help me if you find anything wrong with my circuit connection.

 

[chuckey]

As the maximum current the FET can take is 13V/1K = 13 mA I doubt if this would get the FET smoking. Check your connections.
Frank

 

[Tahsinhossain]

Thanks a lot! I showed it the wrong way in the drawing before but while hooking it up I did it correctly. Actually I changed my dc-dc converter to (NME0515SC ) which is not giving me 15 v, I am thinking this is because the datasheet has an inductor order part and maybe I am not loading it in it's 10% of the rated load which is a must to get it working. I am also not getting anything out from the output of the optocoupler. I think as I am giving around 2.7 v in the input of the optocoupler at pin 2 from the MSP430, do I need to use a BJT to supply the base and get it working? I found the IGBT/MOSFET Gate Drive Optocoupler that they have a transistor in the input. I have checked my connections and they seem to be ok to me now but still not getting anything. Would you suggest me to change the optocoupler? I am struggling to get it working. I really appreciate your help and time.

 

[BradtheRad]

Looking at the lefthand section...

Did you measure Amperes through the led?

What voltage is applied to the 90 ohm resistor?

Does the MSP430 have the same ground as the led?

 

[Tahsinhossain]

Looking at the lefthand section...

Did you measure Amperes through the led?

What voltage is applied to the 90 ohm resistor?

Does the MSP430 have the same ground as the led?

According to MSP430 datasheet it should give 2.7V at output pin. So the current through opto-LED would be 2.7V/90ohm = 30mA (theoretically). But I measured MSP430 pin output as 1.8V. So the current for LED becomes 1.8V/90ohm = 20mA, which is more than required (10mA). But this is not working.

I have used MSP430 ground pin using wire and connected it with pin 3 of the opto. I am not sure what you have meant by same ground as LED. Please share your observations. Thanks a lot.

 

[BradtheRad]

1.
With regard to 'same ground' I was asking if there is a return path for current. You say the MSP430 and led have their ground pins connected, so then it is okay.

2.
Your schematic appears to show the photosensor connected directly to the power supply. There is no inline resistance which would limit current. Did the photosensor at any time get illuminated brightly enough so that it conducted overmuch current?

 

[ud23]

https://www.vishay.com/docs/81227/81227.pdf
**broken link removed**

calculate the your RG value

Rg= (Vcc-VEE -Vol)/ Iol(peak)

where Vol= low level output voltage of the gate driver opto coupler.