TD351 application example

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2 TD351 application example

A TD351 application example is shown in Figure 3. In this example the device is supplied by a +16V

isolated voltage source. An optocoupler is used for input signal galvanic isolation. The IGBT is driven by

44

Ω for turn-on and 22Ω for turn-off thanks to the use of two gate resistors and one diode: sink and

source currents can therefore be tuned independently to help and solve EMI issues. Power switch drivers

are used in very noisy environment and decoupling of the supplies should be cared. In the application

example the decoupling is made by a 100nF ceramic capacitor located as close as possible to the TD351

in parallel with a bigger electrolytic capacitor.

Figure 2. IGBT modules

Figure 3. TD351 application example

VH

10K

11V

100nF

4K7

10nF

100pF

16K

470pF

16V

22

Ω

22

Ω

1

2

3

4

5

6

7

8

TD351

CD

IN

VREF

LVOFF

OUT

VL

CLAMP

VH