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IRISMPS3

Fig 6) Drain (D) voltage of IRIS4013K (CH1) and the FB pin voltage (CH3) at 110VAC in/no load output

Fig 6) again shows the drain and FB pin voltages, but this time with a 110VAC and a no load condition. In

this case the circuit is operating in the PRC mode with a fixed off time of 50us as can be seen on the waveform.

The on time is very short as the only energy required is the energy needed to keep the circuit operating and

hold the output at 15V. Under these conditions the input power consumed is 488mW, which meets the

Energystar and Blue Angel Requirements.

Fig 7)Drain (D) voltage of IRIS4013K (CH1) and the FB pin voltage (CH3) at 230VAC in/no load output