Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob

 Advantages and selection of GD with CT technology for fast SiC driving

lock attach
Attachments are accessible only for community members.

 Advantages and selection of GD with CT technology for fast SiC driving

Andreas_Zhao
Moderator
Moderator
Moderator
First like given 10 sign-ins First question asked

For power electronics design, every power switch needs gate driver, specially the robust and reliable driver is determinant to be outperformed on SiC application. SiC switching speed is so fast to generate higher dv/dt with common mode transient up to 50V/ns.  Further, it requires well-matched propagation delays for minimal switching deadtime.  

here are key advantages of Coreless transformer technology to solve this problem.

  • Robust common-mode transient immunity (CMTI) up to 200kV/us.

In PWM control signal, common-mode interference is general issues by high dv/dt of SiC switch between primary and secondary side of driver IC. Below figure shows the leakage current by coupling capacitance Cpar2 and Cpar1 at half bridge circuit, which would result in mis triggering pulse of gate driving signal. Infineon CT technology can withstand higher dv/dt in comparison with optocoupler.  

Andreas_Zhao_0-1652868017385.png
  • Accurate timing propagation control

    In comparison with traditional RC external filters, this driver has accurate ramp-based generator integration.   Below shows the relation of charging time versus capacitor voltage in this driver IC inside.   This ensure this input to output propagation distortion is only 15ns in the datasheet, which may minimize the deadtime for high accuracy.

    Andreas_Zhao_1-1652868017388.png

     

    If the switching frequency of customer’ design target is 100kHz with the duration of  10us cycle , minimal duty cycle is about 1%,  this is minimal switching on time is 100ns required in SiC driving. So 1ED3125 as right selection is recommended with short propagation of less than 100ns rather than RC filters.   

Attachments
0 Likes
228 Views