Hi I am trying to simulate a very basic Class D audio power amplifier. My problem I have is there appears to be shoot through current between my two swtiching nmos mosfets. I tried avoiding the shoot through current by implementing the dead time control, but it doesn't seem to stop the shoot through currents. An example is when output A is and output B pulses high, output A tends to have a tiny spike has output B pulses high. This tiny spike causes the two nmos mosfets to turn on at the same time causing a shoot through current. Is there anything I am doing wrong that I have done that would cause the low output to have a tiny spike when the other output goes high?
Red is the Shoot-through current, White is the low-side gate drive voltage and Green is the high-side gate drive voltage from the Outputs A and B. As you can see with even dead time implemented, the lowside voltage has a spike as soon as the highside voltage pulses high. Is there something I am doing wrong that is causing the gate driver output to behave weirdly. This is my bachelors thesis topic and I need help with this because the shoot through current is causing very bad power efficiency of around 40%-50%. I am trying to make sure it stays in the 80%-90% region.
Below I attached the Gate driver spice model and the Amplifier schematic.
https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/3312.Spike-.JPG
Red is the Shoot-through current, White is the low-side gate drive voltage and Green is the high-side gate drive voltage from the Outputs A and B. As you can see with even dead time implemented, the lowside voltage has a spike as soon as the highside voltage pulses high. Is there something I am doing wrong that is causing the gate driver output to behave weirdly. This is my bachelors thesis topic and I need help with this because the shoot through current is causing very bad power efficiency of around 40%-50%. I am trying to make sure it stays in the 80%-90% region.
Below I attached the Gate driver spice model and the Amplifier schematic.
https://e2e.ti.com/cfs-file/__key/communityserver-discussions-components-files/196/3312.Spike-.JPG
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