Abstract: An LED driver of an LED tube includes: an AC-to-DC converting module converting an AC voltage received from a ballast into an intermediate DC voltage that is smaller than or equal to a predetermined threshold voltage, and a DC-to-DC converting module converting the intermediate DC voltage into a DC output voltage for driving LEDs of the LED tube.

Abstract: An LED driver of an LED tube includes: an AC-to-DC converting module converting an AC voltage received from a ballast into an intermediate DC voltage that is smaller than or equal to a predetermined threshold voltage, and a DC-to-DC converting module converting the intermediate DC voltage into a DC output voltage for driving LEDs of the LED tube.

Abstract: A flyback converter includes: a transformer including a primary winding and a secondary winding; a first switch coupled to the primary winding; a first control module configured to control the first switch; a second switch coupled to the secondary winding; and a second control module configured to control the second switch, such that the second switch operates in an ON state during a first time period and during a second time period which follows the first time period, and such that a current flowing through the secondary winding has a direction during the second time period opposite to that during the first time period.