Modules in parallel

Giovanni

For 2 or 4 CAB425M12XM3 modules or similar in parallel, for me it is preferable to drive them with a single gate driver, obviously of adequate power. Is this correct or can I use a gate driver for a single module? What does Wolfspeed recommend?

TBhatia

Hello, thank you for your message. A member of our technical team is looking into your questions and we will respond shortly. 

AustinC

Hi Giovanni,

You can use either method to operate XM3 modules in parallel. If you use a single gate driver, we recommend including individual output buffer stages located close to each power module to ensure low parasitic inductance and high drive strength are achieved. If you decide to use independent gate drivers, it's important to select driver ICs with low part-to-part timing jitter so the turn-on and turn-off transitions are synchronized. Make sure to also utilize low-tolerance or precision resistors and capacitors in any filtering in the PWM's signal chain.

If you'd like to simply use a strong gate driver to operate the modules in parallel (without adding discrete output buffer stages per module), then we recommend to include per-module gate and kelvin-source resistors as shown below. They should be sized such that 2/3 of the desired resistance is on the gate resistor and 1/3 of the resistance is on the kelvin-source resistor.

Best Regards,

Austin C.

Giovanni

Perfect.

Thanks and regards