Circuit producing candle-flicker light output from lamp

Claim 1

A circuit for producing a flickering candle-like light output from a lamp, comprising: a lamp circuit having first and second power terminals for connection to an alternating-current power line, and a switch means with a control electrode and having first and second electrodes between which a conductive path is established during alternate half cycles of power-line voltage when the switch means is gated on by a gating signal on the control electrode, the first electrode being connected to the first terminal, and the second electrode and second terminal being adapted for connection to the lamp; and electronic means connected to the lamp circuit to receive power therefrom, and including an electronic oscillator for producing a train of gating signals at an output terminal coupled to the control electrode of the switch means, the gating signals constantly varying in phase with respect to alternating current from the power line whereby a substantially randomly varying lamp-driving current is produced when the lamp is connected between the second terminal and the second electrode so the lamp produces a flickering light simulating candlelight, the oscillator having a feedback input terminal and including feedback circuit means connected between the output terminal and the feedback input terminal for forming a feedback loop so operation of the switch means affects phasing of the gating signals.