Other Parts Discussed in Thread: CSD88537ND
We developed motor driver with the DRV8711 driver and CSD88537ND mosfet almost similar to the design in the following blog:
e2e.ti.com/.../spin-it-designing-your-own-motor-drive-and-control-system-part-4
We have added gate resistors because we use a 2.8A motor. During EMI testing we discovered the following:
120R Gate resistors at low side only will not pass the EMI test.
120R Gate resistors at low and high side will not pass the EMI test
240R Gate resistors at low and high side will just pass the EMI test
We used the following settings: IdriveP = 50mA, IdriveN = 100mA and Tdrive = 250ns (larger drive currents gave worse results)
My questions:
1)
In the datasheet there is mentioned only place 47R to 120R gate resistors at the low side. With these resistor values we will not pass the EMI test.
Can we use the 240R resistors (or even higher) so we can pass the EMI test?
2)
Are there settings (besides Idrive and Tdrive) which we can check to improve EMI?
3)
Are there any other options to improve EMI (based on the design from the blog)?
