Broadcom ACPL-337J, Reference Manual

Page: 14 / 38

Broadcom ACPL-337J-EB600-RM100
14
ACPL-337J Reference Manual Infineon EasyPIM™ 1B IGBT Module EB600-337J Evaluation Board
Figure 5: (a) 24V/5V Power Supply of the EB600-337J Board, and (b) the Isolated 5V/5V Power Supply
Figure 6: 24V/+15V/–15V Isolated Gate Driver High-Voltage Side Power Supply
4.2 Gate Driver Circuit
The used optocoupler-based IGBT gate drivers, ACPL-337J, feature fast signal propagation, desaturation detection, soft
shutdown protection, active clamping, and fault feedback.
Figure 7 shows the both the low-voltage and high-voltage side
gate driver circuit.
Figure 7: Isolated Gate Drive Based on ACPL-337J
4.2.1 Gate Driver Circuit: Low-Voltage Side
Figure 8 shows the low-voltage (digital) side of the driver circuitry. The low-voltage side of the driver is supplied with +5V on
the VCC1 pin. The UVLO and FAULT signals are pulled up to +5V with 10-kΩ resistors. These signals are active high when
driver is working in the specified range of operation. Two 330-pF capacitors are added as a support for these signals
according to the data sheet. The low-voltage side of the gate driver IC optocoupler contains an integrated LED driver with
high-impedance input for interfacing with the controller. The LED driver output must be connected to the recommended split
resistors to the anode pin to achieve the rated common mode rejection. It is recommended to have 1:1 split ratio. These
resistors help balance the common mode impedances at the anode and cathode. This equalizes the common mode voltage
changes at these pins therefore ensuring high common mode rejection performance. According to the data sheet, 150Ω
resistors are connected on the ACPL-337J anode and cathode pins.
a) b)