This is a simple-minded design tool that allows you to calculate component values MC34063A simple switcher chip. It displays the appropriate scematic diagram (step-up, step-down, or inverting) and checks for current and voltage limits. Feedback resistors are chosen from standard component values so that the output is as close to desired value as possible.
Typical input capacitor value is about 100uF, all electorlytics need to be low ESR types. The fast schottky diode should be sufficent for a current needed, 1N5818, 1N5819, 1N5820 and alike will do just fine.
Higher output currents are possible with external switching element, but going to different device is probably more effective these days. See my LM2576 simple switcher component calculator, for example.
For real-life example how to make the output voltage switchable see my EPROM programmer project.
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