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If you are considering using it in a mass produced design, build a prototype first to make sure it's OK in all environmental conditions it may be exposed to; eg. if it's in a sealed enclosure with other components generating heat, you need to see how the whole system works and parts interact.
From data sheet. (ST version)
Rsc 0.33 = 1A So the switch will open up at 1A and keep away from the 1.5A absolute limit.
I did not go through the math but the schematic in post #1 looks like the current will start at 400mA and turn off at 800mA in a typical cycle which will result in 600mA average. I don't see a prolbem. With the switch open the current in the diode will go from 800mA sloping back down to 400mA.
I built the circuit on a vero board.I placed a small coil inductor (220uH - 4X6 size) & also placed a 220uF on the output instead of a 470uF capacitor.All other parts remains as in my first post schematic.
The coil gets really hot within the first two seconds.Really hot & comes with a bad smell.I turned it off immediately.I guess that the inductor is not enough.Going to add a high current inductor.I will tell the progress.
Good news guys.
I replaced the inductor with a bigger one, 220uH Results good.Did a load test by loading a 600mA continuous current.The IC is getting some heat. Is it normal? Here is the schematic of my values.
Is there any method to lower down the heat in IC...!!!