Dimmer control leakage pull down using main power device in flyback converter

A powered LED circuit comprising:

• a flyback converter comprising:
• a rectification system configured to produce a chopped and rectified AC voltage by rectifying a chopped AC voltage from a dimmer control, each cycle of which has an off period which is substantially attenuated but not zero due to leakage of the dimmer control and an on period which substantially tracks the AC voltage, the ratio of the off period to the on period being dependent upon a setting of the dimmer control;
• a transformer having a primary winding and a secondary winding;
• a switching system configured to controllably deliver current into the primary winding of the transformer;
• and
• a flyback controller configured to generate a switching signal that causes the switching system to deliver current to the primary winding of the transformer while the switching signal is in an on state and to stop delivering that current while the switching signal is in an off state, the flyback controller comprising a control circuit configured to generate the switching signal based on the chopped and rectified AC voltage such that the switching signal:
• controllably oscillates between its on and off states during the on periods of the chopped and rectified AC voltage so as to controllably regulate the current that is delivered by the secondary winding of the transformer;
• and
• is in the on state during the off periods of the chopped and rectified AC voltage, thereby preventing a voltage build up from the dimmer control leakage;
• and
• one or more LEDs configured to receive current that is delivered by the secondary winding of the transformer.

A flyback controller for generating a switching signal that causes a switching system in a flyback converter to deliver current to a primary winding of a transformer in the flyback converter while the switching signal is in an on state and to stop delivering that current while the switching signal is in off state, the flyback controller comprising:

• means for receiving a dimmer signal reflective of a chopped and rectified AC voltage, each cycle of which has an off period which is substantially attenuated but not zero due to leakage of a dimmer control from which the chopped AC voltage originates and an on period which substantially tracks the AC voltage, the ratio of the off period to the on period being dependent upon a setting of the dimmer control;
• and
• means for generating the switching signal based on the dimmer signal from the means for receiving such that the switching signal:
• controllably oscillates between its on and off states during the on periods of the chopped and rectified AC voltage so as to controllably regulate the current that is delivered by a secondary winding of the transformer;
• and
• is in the on state during the off periods of the chopped and rectified AC voltage thereby preventing a voltage build up from the leakage.

A powered LED circuit comprising:

• a flyback converter comprising:
• means for producing a chopped and rectified AC voltage from a chopped AC voltage from a dimmer control, each cycle of which has an off period which is substantially attenuated but not zero due to leakage of the dimmer control and an on period which substantially tracks the AC voltage, the ratio of the off period to the on period being dependent upon a setting of the dimmer control;
• a transformer having a primary winding and a secondary winding;
• means for controllably delivering current into the primary winding of the transformer;
• and
• means for generating a switching signal that causes the means for controllably delivering current to deliver current to the primary winding of the transformer while the switching signal is in an on state and to stop delivering that current during while the switching signal is in off state, the means for generating causing the switching signal to be based on the chopped and rectified AC voltage such that the switching signal:
• controllably oscillates between its on and off states during the on periods of the chopped and rectified AC voltage so as to controllably regulate the current that is delivered by the secondary winding of the transformer;
• and
• is in the on state during the off periods of the chopped and rectified AC voltage, thereby preventing a voltage build up from the leakage;
• and
• one or more LEDs configured to receive current that is delivered by the secondary winding of the transformer.