AN4030

Gate to cathode capacitor, impact on dV/dt immunity

Doc ID 022635 Rev 1

9/15

Figure 8.

IEC 61000-4-4 test configuration

Table 3 and Table 4 give the test results for the two previous sample Triacs (logic level and

snubberless) with and without gate to cathode capacitor. A burst test is carried out for each

coupling mode (to line, to neutral, and to line and neutral). Only the minimum burst level

before turn-on, for all coupling modes, is recorded in these two tables.

Table 3.

IEC 61000-4-4 tests results with logic level Triac - sensitive device

Without gate to

cathode capacitor

With gate to

cathode capacitor

(100 nF)

Sample 1 Sample 2 Sample 1 Sample 2

Sample 1

Sample 2

Minimum held

burst level (kV)

1.3

1.3

3.6

3.5

3.3

3.2

Table 4.

IEC 61000-4-4 test results with snubberless Triac - less sensitive device

Without gate to

cathode capacitor

With gate to

cathode capacitor

(100 nF)

Sample 1 Sample 2 Sample 1 Sample 2

Sample 1

Sample 2

Minimum held

burst level (kV)

> 4.5

> 4.5

> 4.5

> 4.5

> 4.5

> 4.5

CGK

RG

1 nF

X2

L

N

Reference plane

10 cm

Burst

generator

Coupling

network

PE

PE