I'm having trouble with the ir2110 output. I'm working on a class d full bridge amplifier and I use 2 ir2110 to drive 4 irf540N mosfets. The switching frequency I use to generate the PWM is 240kHz and I include a 100ns dead-time (ideally would be no more than 50ns), but still got some peak in the output that generates shoothrough. In the picture you can see the circuit, that includes a snubber, the filter and load. The 2VM voltage is 15V.
The problem I need help with is that the deadtime is correct at the input of the ir2110, but in the output i get a peak (circled in red) which is causing the problem and I don't know what causes it. I tried with different values for the gate resistance of the MOS's, but when using a smaller value, 10ohms for example, the shootthrough is indeed smaller but not as small as I would like it to be, and the strange peak behaviour persists.
I get this shootthrough current:
The MOS capacitance and charge characteristics are as follows
In real life, I made the PCB and I'm getting the exact same result as in the simulation.
Thanks in advance.
Best Answer
The IR2110 is designed to supply +/-2A to drive the gate of your output devices.
You have an asymmetric drive caused by the 47 Ohm and diode across it.
You have not specified what 2VM1 is, but assuming it's no more than a 15V supply your maximum gate drive current is about 0.3A during turn on. During turn off you may be exceeding the gate drive capability of the IR2110 since you then have 47 Ohm with whatever the effective Vf slope resistance of the diode is (along with a 0.8-0.9V offset).
I'd suggest you could remove D2, 3, 5, 6 and replace the 47 Ohm with 10 Ohm resistors. This will make the turn on/off delays the same which is important. With a 15V VCC that will give you 1.5A charge/discharge current.