Converter

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

When i want 5V switching regulator (mini project),so i am used input is 9V battery.
The good circuit for work is the IC LT1073-5 (see detail in www.linear.com), it out put 100mA current.
The zener diode is 1N5818,L1 = 100uH
Detail more please see in image.
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I want mini size switching regulator,so it input voltage 9V to 3V Step-Down Converter circuit.
The LT1073 is good idea,it used for dc to dc converter.
if want it,please read in http://www.linear.com .
Vout 3V at 100mA, L1 100?H , D1 - Diode 1N5818 or equiv
Detail more,please in image.
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