AN3106

Transformer specifications

Doc ID 16775 Rev 2

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9

Transformer specifications

General description and characteristics

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Application type: consumer, home appliance

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Transformer type: open

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Coil former: horizontal type, 7 + 7 pins, two slots

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Max. temp. rise: 45 °C

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Max. operating ambient temperature: 60 °C

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Mains insulation: acc. with EN60950

Electrical characteristics

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Converter topology: half-bridge, resonant

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Core type: ETD34-PC44 or equivalent

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Min. operating frequency: 70 kHz

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Typical operating frequency: 100 kHz

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Electrical diagram and winding characteristics

Figure 39.

Transformer electrical diagram

a.

Measured between pins 2-4.

b.

Measured between pins 2-4 with only one secondary winding shorted. Difference between the two measured

leakage inductances has to be < 10%.

Table 6.

Transformer winding data

Pins

Winding

RMS current

Number of turns

Wire type

2-4

Primary

47

#30 x 0.1 mm - G2

8-10

1.

Secondary windings A and B have to be wound in parallel.

9

#60 x 0.1 mm - G2

12-14

Sec. - B4(1)

9

#60 x 0.1 mm - G2

6-7

2.

Aux. winding is wound on top of primary winding, turns are close each other, placed on external side of the

coil former.

3

0.28 mm - G2