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KIT8020CRD8FF1217P-1_UM Rev -
User Manual
7. Example Application and Measurements
7.1 Board Setup
In order to demonstrate the EVL with SiC devices, a synchronous phase-leg Buck
converter configuration is used as an example to evaluate the performance of the SiC
EVL board. This is option one configuration on table 1. The table below gives the
electrical parameters. Please note the switching frequency is at 40KHZ in this case
due to the design limitation of the available inductor, but it does not mean the
switching frequency is limited to 40KHZ. Because of low switching losses of SiC
MOSFET, the switching frequency can increase to higher without sacrificing much
switching losses when using SiC MOSFET. The purpose of 40KHZ setting is
competing with 1200V Si IGBT for inverter application with this phase-leg
configuration, which frequency is normally ranged from 15KHZ to 20KHZ.
In the testing, two 25mohm SiC MOSFETs are assembled on the PCB board with
heatsink for both high side Q2 and low side Q1. The figure gives the test setup with
EVL boards. The signal generators are used to generate high side and low side PWM
signals with Input_HS and Input_LS. Note that the dead time period must be applied
to the input signal between Input_HS and Input_LS.
Table. 3 Electrical parameters
Items
Parameters
Input Voltage
600Vdc
Output Voltage
300Vdc
Output RMS Current
30A
Output Power
9KW
Peak MOS current
40A
Switching Frequency
40KHZ
Duty Cycle
50%
Dead time
~450ns
Inductor
400uH
Output Capacitors
300uF
Cree Discrete SiC EVL Board
Gate drive
Q2
Q1
CON1
CON3
CON2
CON5
600V
DC source
400uH
300uF
RL
Cin
Input_LS_RTN
VCC
VCC_RTN
Input_HS
Input_HS_RTN
Input_LS
4.10
4.9
4.8
4.7
4.6
4.5
CON4
PWM signal
generator
+12V
DC supply
CRD8FF1217P-1
Figure 5. Test setup for the EVL boards with CRD8FF1217P-1
