DocID025572 Rev 1

11/19

AN4407

Description

19

In fact, the real voltage across the gate and source pin, equal to the difference between the

driving voltage and the parasitic overvoltage, becomes positive and fully equivalent to the

extra voltage generated.

This aspect is confirmed by the waveform comparisons between the tests with a standard 3-

pin solution and the 4-pin alternative. In Figure 14, this specific aspect is shown.

Figure 14. Turn-off comparison between 3 pin and 4 pin solution

The improvement in terms of reduction of power loss is also present when the value of

Figure 15. Turn-off energy comparison @ different Rg values

1.2.2

Turn-on

the positive extra-voltage generated over the stray inductance introduces a turn-on delay,

increased total switching power dissipation (Figure 16).

GIPG261120131627FSR

GIPG261120131635FSR