Broadcom ACPL-337J, Справочное руководство

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Broadcom ACPL-337J-EB600-RM100
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ACPL-337J Reference Manual Infineon EasyPIM™ 1B IGBT Module EB600-337J Evaluation Board
ATTENTION: Signals dedicated for high-side and low-side drivers, in one inverter leg, need to have proper dead time. The
board itself does not provide dead-time generation. The recommended minimal dead time is 5 µs.
Figure 8: Isolated Gate Driver ACPL-337J Primary Side
4.2.2 Gate Driver Circuit: High-Voltage Side
Figure 9 shows the high-voltage side of the gate driver circuitry. It consists of bypass capacitors, a DESAT protection circuit,
and a driver output stage. The DESAT protection circuit is described in Section 4.2.3, Protection Features . The output stage
of the ACPL-337J is supplied with +15V and –15V. These voltages are supported with 1-µF bypass capacitors that provide
large transient currents that occur during switching transition. The VOUT pin supplies the gate of the IGBT with the
necessary voltage and current. In series with this pin, an appropriate gate resistor is added. Selection criteria for the gate
resistors is described in
Section 4.5, Temperature Measurement . There are three positions on every gate driver where gate
resistors are placed. This is done to enable the customer to quickly adjust gate resistance. Also, this circuitry features a turn-
off diode that serves to adjust turn-on and turn-off gate resistance separately. Equivalent turn-on gate resistance is defined
by two parallel resistors (R7 and R9 in
Figure 9 ) in series with the third resistor (R8 in Figure 9 ). Similarly, turn-off gate
resistance is defined only by two resistors connected in parallel (R7 and R9) because the third is bypassed by the diode (D7
in
Figure 9 ). In case of a faulty power supply or unexpected overvoltage, the TVS diode placed between the gate and the
emitter of the IGBT, and it ensures that no damage is done to the IGBT gate structure. Voltage is limited to ± 18V.
Figure 9: Isolated Gate Driver ACPL-337J High-Voltage Side
4.2.3 Protection Features
A typical power stage of the three-phase inverter is susceptible to several types of failures, related to the short circuit, which
can potentially cause destruction of the IGBT. To prevent damage to the inverter, fault detection must be implemented to turn
off the IGBTs in case of an overcurrent event. The ACPL-337J provides an ideal solution combining local desaturation
detection and soft shutdown with high-speed current output and high-voltage optical isolation. The DESAT part of the gate
circuit is marked with a red rectangle in
Figure 10 .