How to reduce EMI in EPS totem pole drivers?

The totem-pole output stage used to drive MOSFETs/IGBTs in an EPS (Electric Power Module) also generates noise during its switching operation. Measures to reduce EMI include:

1. Optimizing totem-pole transistor parameters: The switching speeds of the pull-up/pull-down transistors (usually NPN/PNP or N-MOS/P-MOS) should be matched to avoid a "shoot-through" state where both transistors are partially conducting simultaneously, generating large current spikes.

2. Increasing totem-pole power supply decoupling: Connecting high-quality high-frequency ceramic capacitors (such as 0.1μF and 10μF in parallel) in parallel between the power supply pins (VCC and ground) of the totem-pole circuit provides transient large current and suppresses noise on the power lines.

3. Connecting a small resistor in series: Connecting a small resistor (a few ohms) in series between the totem-pole output and the final output of the driver chip can slow down the edges of the drive signal, thereby reducing ringing caused by parasitic inductance of the drive line.

4. Ensuring a clean reference ground: The ground of the totem-pole circuit should be connected to the same clean point as the ground of the driver IC and return directly to the ground terminal of the filter capacitor of the drive power supply.