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IRISMPS1

Fig 5) Drain (D) voltage of IRIS4007K(CH1) and the FB pin voltage(CH2) at 36VDC in/0.1A load output

Fig 5) again shows the drain and FB pin voltages, but this time with a 36VDC and a light load condition

of 0.1A (0.5W output power). Again the quasi-resonant effect can be seen by the quarter wave signal on

the drain pin and also at the FB pin. Note the very short on time, and the fact that the current ramp voltage

at the FB pin does not start from zero, this is due to the offset voltage generated from the voltage feedback

loop across R8.

Fig 6)Drain (D) voltage of IRIS4011 (CH1) and the FB pin voltage (CH2) at 230VAC in/0.1A load output