Circuit Project Electronic

The single-ended primary inductance converter (SEPIC)
shown in Figure 3 IC LT1618 is ideal for applications where the
output must reduce to zero during shutdown. The input
current limit not only helps soft-start the output but also
provides short-circuit protection, ensuring USB device
compliance even under output fault conditions.
Read More Source:
http://www.linear.com

If you want DC converter 5V to 15V Step-Up voltage.
I like IC LT1073,It is important part of this circuit.
15V OUTPUT
100mA AT 4.5VIN
Detail more, Please read in this image circuit.
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The circuit is very simple, and is easily made on Veroboard or similar. Construction is not critical, and the schematic is shown in Figure 1 below.
Rectifier diodes should be ultrafast (UF4004 or similar), or you can use 1N4148 signal diodes. Losses will be slightly higher if you use signal diodes, or lower if [...]