its a Brush servo motorMaybe use a Mosfet driver MIC4427 etc,
What is the nature of the load ?
the reason I used the lm318 is because I set the frequency of my signals to only 4kHZ, therefore I though those op amps would be fast enough. what's a faster device you suggest I use for this application? I really think that the issue is that the corresponding mosfets are not getting turned on/off fast enough.Why are you using slow analog op amps to drive the digital signals to the MOSFET gates?
You should be using a much faster device as drivers.
Thank you for your reply. If you don’t mind me asking, how could I possibly address the speed concern? Would I need dedicated high side and low side drivers rather than the op amps?As stated earlier, use proper MOSFET gate drivers. Most likely the switching time for your P-channel MOSFETs is too slow, which if not the cause of the dead transistors, certainly does not help the efficiency. See MaxHeadRoom's comment in post #4.
You have two, now make that three people concerned about dead time. The slow speed of your P-channel device may be part of the reason. Do you even have dead time in the drive waveforms?
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"Only 4kHz" should be rephrased for your circuit as, "the very high frequency of 4kHz".I set the frequency of my signals to only 4kHZ
Thank you for asking. To turn a MOSFET on or off it is necessary to put a charge into to take a charge out of the MOSFET's gate. This often done with driver integrated circuits because to switch quickly you need amps of drive. The LM318 is a nice and pretty fast op amp, but if falls way short of being able to drive any but the smallest MOSFETs.Thank you for your reply. If you don’t mind me asking, how could I possibly address the speed concern? Would I need dedicated high side and low side drivers rather than the op amps?
There are many dedicated drivers that have both high and low side outputs.Would I need dedicated high side and low side drivers rather than the op amps?
Using an op amp as a comparator is sort of like using a screwdriver as a hammer.the reason I used the lm318 is because I set the frequency of my signals to only 4kHZ, therefore I though those op amps would be fast enough. what's a faster device you suggest I use for this application?
I tried that once. It did not go well.... like using a screwdriver as a hammer.
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Clear case of not the right size screwdriver, you see it quite often.I tried that once. It did not go well.
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