Reverse Biased SOA

In order to saturate the power switch and reduce

conduction losses, adequate direct base current

100

transistor to turn off (retrace phase).

Most of the dissipation, especially in the deflection

application, occurs at switch-off so it is essential

new set of curves have been defined to give total

KHz scanning frequencies for choosing the

optimum negative drive. The test circuit is

illustrated in figure 1.

The values of L and C are calculated from the

following equations:

1

2

L

1

2

C

ω = 2 πf =

1

√

flyback voltage, f= frequency of oscillation during

retrace.

BASE DRIVE INFORMATION

BUW1215

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