Broadcom ACPL-355JC Reference Manual page 14

ACPL-355JC Reference Manual
Figure 5: +15V/+5V DC/DC Switching Regulator Circuit
EB1200M62-355JC is equipped with a nonisolated switch mode power supply (SMPS), which provides 5V for the ICs on the
low-voltage side. The +15V/+5V power supply is realized with an LM2674 DC-DC switching regulator, as shown in
The +5V output is used to supply the low-voltage side of ACPL-355JC gate drivers and the isolated SMPS controller IC. The
+5V power supply is capable of driving a 500-mA load and supplying all ICs on the board.
The power for the high-voltage side of the gate drivers is realized with the isolated SMPS, which provides two dual outputs
of +14V and –4V.
Since SiC MOSFETs from various manufacturers have different recommended gate voltage levels, the power supply for the
gate driver high-voltage side is designed to be configurable. There are two adjustments that must be done before the board
can be used on a MOSFET with a different part number.
The first parameter to be configured is the input voltage of the isolated SMPS. This is achieved by adjusting the

feedback resistor R49 of the adjustable LDO voltage regulator, shown in
LD1086 is calculated as follows:
The minimum value for V
behavior.
The second parameter is the Zener diodes D20 and D25 placed in the output stage of the SMPS, which define the

positive gate driver voltage, shown in
recommended by the power module manufacturer should be used.
The presented adjustable circuitry enables in-depth evaluation of switching characteristics or benchmarking of SiC modules
in a 62-mm package from different semiconductor manufactures.
Broadcom
is limited by the isolated SMPS to 10V. Do not adjust V
o
Figure 7. A diode with a Zener voltage equal to the positive gate voltage level
62-mm SiC Module EB1200M62-355JC Evaluation Board
Figure 6. The output of the adjustable LDO
below 10V to avoid unexpected board
o
Figure 5.
ACPL-355JC-62mmSiC-RM100
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