August 2009

Doc ID 13406 Rev 3

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BUL741

BUL741FP

High voltage fast-switching NPN power transistors

Features

■ High voltage capability

■ Low spread of dynamic parameters

■ Minimum lot-to-lot spread for reliable operation

■ Very high switching speed

Applications

■ Electronic ballast for fluorescent lighting

■ Switch mode power supplies.

Description

The devices are manufactured using high voltage

multi-epitaxial planar technology for high

switching speeds and high voltage capability.

Thanks to an increased intermediate layer, it has

an intrinsic ruggedness which enables the

transistor to withstand an high collector current

level during breakdown condition, without using

the transil protection usually necessary in typical

converters for lamp ballast.

Figure 1.

Internal schematic diagram

TO-220FP

1

2

3

TO-220

1

2

3

Table 1.

Device summary

Order codes

Marking

Packages

Packaging

BUL741

BUL741

TO-220

Tube

BUL741FP

BUL741FP

TO-220FP

Tube

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