How do I tune the RC interface for driving Infineon CoolGaN GIT HEMTs 600 V? (infineon 2EDF7275K Driving CoolGaN GIT HEMTs 600 V User Guide infineon 2EDF7275K Driving CoolGaN GIT HEMTs 600 V User Guide)

Answer

manuals.plus

Feb 24, 2025 - 03:42 AM

To tune the RC interface for driving Infineon CoolGaN GIT HEMTs 600 V, you can follow the general tuning rules provided in the user guide. Here are the steps:

1. Rss tuning: Rss is the steady-state gate current tuning resistor. It should be tuned according to the gate voltage VDD, gate diode forward voltage drop VF (3~4 V), and the desired on-state gate current Iss. Reference Rss selection values for different RDS(on) devices are provided in Table 1 of the user guide.

2. Rtr tuning: Rtr is the transient switching speed dv/dt tuning resistor. It should be tuned according to the desired switching slew rate in different applications. In hard-switching conditions, a low Rtr is desired to achieve a high slew rate and reduce hard-switching loss. A typical Rtr value for RDS(on,typ) = 140 mΩ device is within the range of 20 to 50 Ω with VDD = 8 V. This value can be scaled to other ohmic class devices according to the desired slew rate. In soft-switching conditions, the selection of Rtr is less critical.

3. CC tuning: CC is the gate coupling capacitor used as a charge pump to provide fast-switching transients as well as negative gate bias. CC should be tuned according to the desired negative gate voltage bias -VN during the transistor off-state. The value of CC can be quantified based on the equation provided in the user guide, considering the equivalent switching gate charge (QGeq). In hard-switching conditions, VN is recommended around 4 to 5 V, while in soft-switching conditions, VN can be lowered down to 2 V or even close to zero.

By following these tuning steps, you can optimize the RC interface configuration for driving Infineon CoolGaN GIT HEMTs 600 V. For more detailed information and reference values, please refer to the user guide provided by Infineon.