Isolated ground planes on a MCU controlled high voltage IGBT

[stube40]

Re: Isolated ground planes on a MCU controlled high voltage

I cant tell yu how helpful this thread has been!

If I put -15V / +15V across Vee/Vcc of the VO3120, wont I be putting 30V across the gate/emitter of the IGBT meaning that I exceed the maximum allowable Vge for many IGBTs? I thought that 15V was the optimum Vge.

Maybe I shouldn't think so much and should just listen

 

[IanP]

Re: Isolated ground planes on a MCU controlled high voltage

For turn-on a positive gate voltage of 15V [+/-10%] is recommended ..
This value is sufficiently high to fully saturate an IGBT ..
In no case should a gate drive outside of the range of 12 to 20V be used for turn-on ..

Rgds,
IanP

 

[stube40]

Re: Isolated ground planes on a MCU controlled high voltage

For turn-on a positive gate voltage of 15V [+/-10%] is recommended ..
This value is sufficiently high to fully saturate an IGBT ..
In no case should a gate drive outside of the range of 12 to 20V be used for turn-on ..

Rgds,
IanP

I think I misunderstood the Vo output terminal of the VO3120. The datasheet says it can handle a maximum supply voltage (Vcc - Vee) of 35V, whilst the Vo output terminal will always be in the range 0V to Vcc. Hence, if I'm right then with +15V on Vcc and -15V on Vee I will still only be gettting 0V to 15V on Vo. But does this bring me any benefits over using a simpler uni-polar 15V DC/DC and simply putting 0V in Vee and 15V in Vcc?

They dont call me the rookie for nothing!!

 

[elec_designer]

Re: Isolated ground planes on a MCU controlled high voltage

-15V is good against miller effects in power transistor. Then you can hold gate much lower voltages than threshold.