This simple LED torch is driven by a 2-transistor blocking oscillator
which steps up the voltage from a 1.5V cell. It relies on the inherent
current limiting of the 150µH choke to protect the white LED from
over-drive. With a 9V zener diode in place of the white LED, it could
also provide a 9V supply provided the current drain is modest.
Circuit diagram:
No comments:
Post a Comment