MR4530 datasheet(24/43 Pages) SHINDENGEN

24 / 43 page

Shindengen Electric MFG.CO.,LTD

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6.1.3 Resonating capacitor

(1) Selecting the resonating capacitor

The resonating capacitor must have the following characteristics:

1) The withstand voltage is significantly greater than that of the main switching device.

2) Tangent of loss angle tan

δ is small.

3) The upper temperature limit is high.

Ideally, use a mica or polypropylene capacitor. A low-loss ceramic capacitor should also be adequate. Consult with

the manufacturer before using this capacitor type.

(2) Capacity of resonating capacitor

Noise is reduced by the resonance determined by the resonating capacitor and the primary coil inductance. This

has both favorable and adverse effects, as shown in the table below. Consider these effects when setting the

capacity of the capacitor.

Item

Small

← Capacitor capacity → Large

Efficiency during standby

Increases

Decreases

Heat buildup in the transformer

Decreases

Increases

Ringing voltage at turn-off of main switching device

Increases

Decreases

Noise

Increases

Decreases

Operating frequency

Increases

Decreases

6. Supplementary design information

MR4530 Datasheet(PDF) 24 Page - Shindengen Electric Mfg.Co.Ltd