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Password Vol.02-06-e MR2000 Series

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Protection Circuits

Fig.6 Resonance Condenser Discharge Current at ON

Load-Shorting Protection

Inclusion of a load current reduction circuit enables reduction in heating under load and

alleviates stress on the device.

Unnecessary

Discharge current reduced

1

Protection Against Malfunction at ON

The Leading Edge Blank (LEB) prevents malfunctions in the over-current detect circuit

due to discharge current in the partial resonance condenser at ON.

2

Protection Against Malfunction at OFF

Inclusion of the ON-dead timer prevents malfunctions at OFF.

This function ensures that resonant oscillation due to the leakage inductance and the

resonance condenser at OFF, are recognized as trigger signals, and trigger input is then

masked to prevent switching ON again.

3

Over-current Protection

Over-current protection for the device consists of pulse-by-pulse over-current protection

to detect primary current, and a limitation on the ON width.

4