I have a H-bridge that is being supplied by 12V and using around 10A. I am turning it on/off with a microcontroller that has an output of 0V-5V. The switching frequency is "super low" so the gate charge of the MOSFET is not a problem. I am trying to "convert" this 5V logic to 12V logic (0V-12V), and thought of something like this:
simulate this circuit – Schematic created using CircuitLab
Is there any redundacy, any problem or anything missing from this design? I can see this work, but this will be in "somewhat of a commercial product", and would like it to be as robust as possible.
Answer
I suggest something more like this:
simulate this circuit – Schematic created using CircuitLab
Drive into a 10nF load looks like this:
Edit: The violet trace is your circuit- as you can see, very very slow and it does not have enough swing to turn the MOSFETs off reliably- Vgs(th) can be as bad as 2V (time scale changed to show response of slow circuit).
You really want this circuit to switch rapidly or to insert some dead time- both MOSFETs will be one for a time when it is switching which causes shoot-through current.
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