MC34063 darlington out

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Joined Aug 4, 2017
I was trying to design a low power forward converter which convert 5V to 3v3. I used mc34063 for PWM at 100khz. But in datasheet the saturation voltage typical 1V, max 1.3V for output of 34063. ( it has two transistor as configure darlington in output). Therefore the number of two in transformer can not go zero. 34063 can not push it to ground.(In the photo blue waveform-probe 2). I need to create %50 duty cycle in 100khz. Can anybody help to me ?
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Joined Aug 1, 2013
That looks like a massive amount of work to go through just to drive a linear regulator at the output.

1. Is an isolated output required?

2. What is the required output current?