Circuit having a bidirectional switch for supplying a load from an AC voltage supply

A circuit for supplying a load from an AC voltage supply, said circuit comprising:

• a bidirectional switch coupled in series with the load, the bidirectional switch including two one-way switches connected in antiparallel;
• a control circuit for controlling the bidirectional switch based on a single relatively low DC voltage;
• and
• a third switch and a first resistor coupled in series between a positive terminal of the DC voltage and a control terminal of one of the one-way switches,
• wherein the bidirectional switch is connected to a first terminal of the AC voltage supply, and the DC voltage is referenced to the first terminal of the AC voltage supply.

An apparatus connected to an AC voltage supply and a relatively low DC voltage, said apparatus comprising:

• a load to be supplied by the AC voltage supply;
• a bidirectional switch coupled in series with the load, the bidirectional switch including two one-way switches connected in antiparallel;
• a control circuit for controlling the bidirectional switch based on the DC voltage;
• and
• a third switch coupled to a positive terminal of the DC voltage, the third switch controlling one of the one-way switches of the bidirectional switch,
• wherein the bidirectional switch is connected to a first terminal of the AC voltage supply, and
• the DC voltage is referenced to the first terminal of the AC voltage supply.

An apparatus connected to an AC voltage supply and a relatively low DC voltage, said apparatus comprising:

• a load to be supplied by the AC voltage supply;
• a bidirectional switch coupled in series with the load, the bidirectional switch including two one-way switches connected in antiparallel;
• a control circuit for controlling the bidirectional switch based on the DC voltage;
• and
• a third switch and a first resistor coupled in series between a positive terminal of the DC voltage and a control terminal of one of the one-way switches,
• wherein the bidirectional switch is connected to a first terminal of the AC voltage supply, and
• the DC voltage is referenced to the first terminal of the AC voltage supply.