How it works

A Schmitt-trigger oscillator drives a transistor that stores energy in the inductor. When the transistor turns off, that energy transfers to the output. A zener-controlled feedback path stops oscillation when the output reaches the intended threshold.

The original notes describe roughly 14 V output and around 80% efficiency. Both depend on input voltage, inductor loss, switching behavior, and load; neither is established as a measured specification here.

Original schematic

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Figure 1 · NewCircuits archive · Download image ↓

On the bench

Test with a current-limited source and a defined load. Check transistor and diode peak ratings, inductor saturation current, and output ripple before attaching sensitive electronics.

Resources & provenance

Rewritten from the original circuits/pos/h23n8m9_pos001.php page. Component values and historical performance claims have not been independently bench-tested. The circuit figures have had their watermarks removed.

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