STMicroelectronics STEVAL-IHT005V2, Руководство пользователя

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UM1631 Board immunity performances
6.3.5 Gate filtering circuit influence
The gate filtering circuit has an influence mainly on sensitive devices. When the gate
filtering circuit is removed, the immunity of Z01 decreases to 2 kV and immunity of ACS108
is decreased to 4 kV. Gate filtering circuit is not mandatory to pass IEC-61000-4-4 tests for
ACS108.
There is no influence on 35 mA I
GT
devices, when the gate filtering circuit is removed.
6.3.6 Immunity to relay switching
Relay is connected on the board. The relay cannot be controlled in zero voltage mode.
Switching of the relay produces very high dV/dt, other devices must be immune to this type
of noise. Immunity tests of the devices against relay switching have been performed.
Figure 7 shows turn-off behavior of the relay. (The dV/dt observed during turn-off is
1 kV/µs.) Observed peak voltage during turn-off was +/-1300 V. The dV/dt observed during
turn-on was 4 kV/µs. The load was 1.4 H inductor with serial resistance 12

, (RMS current
0.52 A). The Triacs and ACS/ACST switches were not disturbed by these spikes.
Figure 7. dV/dt behavior during relay turn-off