US Patent 10469077 Electronic switch and dimmer

A novel approach for the control of AC power uses power MOSFETs in a bidirectional switch subcircuit configuration having an optically coupled, electrically floating control circuit that self-biases the switches into the “on” state and uses an optically coupled control element to force the switches into the “off state. The time constant of the control circuit is fast enough to allow phase control as well as on-off control. A plurality of subcircuits can be easily cascaded to provide improved performance.