Abstract: A thin resonant transformer includes a wire bobbin having a spool, an inner winding wound around the spool, a magnetic plate mounted in the wire bobbin, an outer winding wound in the wire bobbin and encompassing the inner winding and the magnetic plate, and two symmetric magnetic cores mounted on the wire bobbin. The wire bobbin has a top provided with a top plate and a bottom provided with a bottom plate. The magnetic plate is arranged between the inner winding and the outer winding. The inner winding, the outer winding, and the two magnetic cores generate a first magnetic circuit. The magnetic plate, the inner winding, and the outer winding generate a second magnetic circuit.

Abstract: A resonant transformer structure includes a secondary wire bracket having a secondary wire groove, and a primary wire bracket having a primary wire groove. The secondary wire bracket is provided with two third wire holders each having multiple auxiliary legs. The primary wire bracket has a fourth wire holder having multiple connecting legs. The primary wire bracket has multiple jump wire gaps. A secondary winding is wound in the secondary wire groove. A primary winding is wound in the primary wire groove. The primary wire bracket extends into the secondary wire bracket. The wire end of the secondary winding does not pass the primary winding. The wire end of the primary winding extends through the jump wire gaps, and is connected to the connecting legs to increase a distance between the wire end of the secondary winding and the primary winding.

Abstract: A resonant transformer with adjustable leakage inductance includes a secondary winding group, a primary winding group, a magnetic sheet and a core group. The primary winding group is provided on a bobbin of the secondary winding group, and the magnetic sheet is provided in the bobbin. The secondary winding group, the primary winding group and the magnetic sheet include a first through hole, a second through hole and a through hole, respectively. The core group includes a first core and a second core symmetrically disposed, which are disposed on top of and at the bottom of the primary winding group, respectively. During operation of the resonant transformer, the degree of coupling between the primary and secondary sides can be changed using the magnetic sheet. This allows the native leakage inductance to be altered to satisfy demands for various different resonant frequencies.

Abstract: An upright composite common mode coil assembly includes a coil carrier and a seat. The coil carries includes two bobbins with a plurality of coils wounded thereon. The seat includes a base, a bottom portion, a top portion and a separating portion. The base has a back plate on a surface thereof, hollow portions formed at an upper position and a lower position thereof, a wire slot and an indentation are provided at either side of the back plate. The bottom portion and the top portion extend vertically from two sides of the base. A recessed portion is formed at each of the corners of the bottom portion, and a pin is inserted into each of the recessed portions. The top portion has a flat top face. The separating portion extends from another surface of the base and tapered to form a curved surface, and form two receiving slots with the top portion and the bottom portion, respectively.

Abstract: A resonant transformer with adjustable leakage inductance includes a secondary winding group, a primary winding group, a magnetic sheet and a core group. The primary winding group is provided on a bobbin of the secondary winding group, and the magnetic sheet is provided in the bobbin. The secondary winding group, the primary winding group and the magnetic sheet include a first through hole, a second through hole and a through hole, respectively. The core group includes a first core and a second core symmetrically disposed, which are disposed on top of and at the bottom of the primary winding group, respectively. During operation of the resonant transformer, the degree of coupling between the primary and secondary sides can be changed using the magnetic sheet. This allows the native leakage inductance to be altered to satisfy demands for various different resonant frequencies.

Abstract: A primary-side regulated (PSR) current control system under a LLC topology includes a voltage polarity converting circuit, a current signal sampling circuit, a current cross-over detecting circuit, a zero current detecting circuit, and a current integrator circuit.

Abstract: An upright composite common mode coil assembly includes a coil carrier and a seat. The coil carries includes two bobbins with a plurality of coils wounded thereon. The seat includes a base, a bottom portion, a top portion and a separating portion. The base has a back plate on a surface thereof, hollow portions formed at an upper position and a lower position thereof, a wire slot and an indentation are provided at either side of the back plate. The bottom portion and the top portion extend vertically from two sides of the base. A recessed portion is formed at each of the corners of the bottom portion, and a pin is inserted into each of the recessed portions. The top portion has a flat top face. The separating portion extends from another surface of the base and tapered to form a curved surface, and form two receiving slots with the top portion and the bottom portion, respectively.

Abstract: An upright composite common mode coil assembly includes a coil carrier and a seat. The coil carries includes two bobbins with a plurality of coils wounded thereon. The seat includes a base, a bottom portion, a top portion and a separating portion. The base has a back plate on a surface thereof, hollow portions formed at an upper position and a lower position thereof, a wire slot and an indentation are provided at either side of the back plate. The bottom portion and the top portion extend vertically from two sides of the base. A recessed portion is formed at each of the corners of the bottom portion, and a pin is inserted into each of the recessed portions. The top portion has a flat top face. The separating portion extends from another surface of the base and tapered to form a curved surface, and form two receiving slots with the top portion and the bottom portion, respectively.

Abstract: A resonant high current density transformer with an improved structure includes a secondary insulating bobbin, a primary insulating bobbin and a core assembly. The secondary insulating bobbin includes a base. Two posts extend from a first side of the base, and a raised plate extends from a second side of the base, the second side is opposite to the first side. The two posts and the raised plate form a receiving space for receiving an insulating sheath having a plurality of sleeves. A secondary winding is provided on each of the sleeve. The primary insulating bobbin having a tunnel is provided at one side of the secondary insulating bobbin. The surface of the primary insulating bobbin is provided with a primary winding and covered by an insulating cover. A core assembly includes a first core and a second core.

Abstract: A resonant high current density transformer with an improved structure includes a secondary insulating bobbin, a primary insulating bobbin and a core assembly. The secondary insulating bobbin includes a base. Two posts extend from a first side of the base, and a raised plate extends from a second side of the base, the second side is opposite to the first side. The two posts and the raised plate form a receiving space for receiving an insulating sheath having a plurality of sleeves. A secondary winding is provided on each of the sleeve. The primary insulating bobbin having a tunnel is provided at one side of the secondary insulating bobbin. The surface of the primary insulating bobbin is provided with a primary winding and covered by an insulating cover. A core assembly includes a first core and a second core.

Abstract: A resonant high current density transformer including two cores that are abut against each other with their first and second side posts on two sides thereof. A first bobbin envelops the first side posts on the same side of the two cores. A side plate is provided on either end of the first bobbin. The space between the two side plates is divided into two coil slots with a spacer, and at least a wire is wound in each coil slot to form a primary winding. A further second bobbin envelops the second side posts on the same side of the two cores. The outer periphery of the second bobbin is divided into two winding regions by another spacer, and a metal plate envelops each of the winding regions to form a secondary winding. A bobbin mount is disposed at the external flank of the second bobbin with a barrier plate at a side thereof for separating the first and the second bobbins.

Abstract: A resonant high current density transformer including two cores that are abut against each other with their first and second side posts on two sides thereof. A first bobbin envelops the first side posts on the same side of the two cores. A side plate is provided on either end of the first bobbin. The space between the two side plates is divided into two coil slots with a spacer, and at least a wire is wound in each coil slot to form a primary winding. A further second bobbin envelops the second side posts on the same side of the two cores. The outer periphery of the second bobbin is divided into two winding regions by another spacer, and a metal plate envelops each of the winding regions to form a secondary winding. A bobbin mount is disposed at the external flank of the second bobbin with a barrier plate at a side thereof for separating the first and the second bobbins.

Abstract: An offset voltage eliminating circuit structure for a protection mechanism of a dimmer is described. The circuit includes a constant current source, a subtractor and a hysteresis comparator. The constant current source is used for outputting a stable current, the output of the constant current source is connected with a dimming signal input through a current-limiting resistor, and the dimming signal input is connected with an output of an external traditional dimmer.

Abstract: An improved structure of a transformer includes a bobbin covering at least a portion of a magnetic core set which has a magnetic loop passing through the bobbin, wherein winding grooves and at least one connecting portion extending sideways are provided on the outer peripheral side of the bobbin, and a plurality of notches with lateral openings are provided on the connecting portion. Coils are wound in the winding grooves of the bobbin. The coils have at least a plurality of line ends, each line end passing through a different notch. One positioning pin is embedded in each of the winding grooves near the lateral opening. The positioning pins hold the respective line ends in place by pressing against them. A casing is fitted on the outer peripheral side of the coils to create separation between the coils and the magnetic core set. The casing is provided with a hollow opening such that the outer peripheral side of the coils facing the airflow is exposed to improve the overall heat dissipating efficiency.

Abstract: An offset voltage eliminating circuit structure for a protection mechanism of a dimmer includes a constant current source, a subtractor and a hysteresis comparator. The constant current source is used for outputting a stable current, the output of the constant current source is connected with a dimming signal input through a current-limiting resistor, and the dimming signal input is connected with an output of an external traditional dimmer. A voltage that causes an offset voltage is created across the current-limiting resistor when a current flows through the current-limiting resistor. An input of the subtractor is connected with the constant current source, and another input of the subtractor is input with an offset reference voltage. A non-inverting input of the hysteresis comparator is connected to the output of the subtractor, while the inverting input of the hysteresis comparator is input with a saw-tooth wave.

Abstract: An isolation dimmer circuit structure includes a control circuit module having an input end for receiving a sensing signal and an output end for outputting a control signal. An optocoupler is provided between the control circuit module and a light source power supply circuit. The light source power supply circuit is further connected to a light source. A protection circuit includes first and second resistors and first and second diodes. The first resistor is connected in series between the positive terminal of a DC power supply and the anode of the first diode, forming a node A, the cathode of the first diode is connected to a first terminal of a control input end connected to a traditional dimmer circuit to form an overvoltage protection mechanism.

Abstract: An improved compact twin-shaft bobbin structure includes penetrating first and second center through-holes on first and second bobbins, respectively. First and second winding slot groups having a plurality of adjacent respective first and second winding slots are provided on the outer peripheral sides of the first and second center through-holes, respectively. First and second receiving recesses laterally extend from ends of the first and second center through-hole, respectively. First and second pin groups and an opening are provided on ends of the first and second receiving recesses, respectively. Two clamping slots are provided on the top and bottom of the second winding slot group, respectively. A shield in the shape of an “n” is provided on one side of the second bobbin. The shield includes bent flanges along two edges thereof. The two flanges are inserted into the two clamping slots, respectively to fasten the shield to the second bobbin.

Abstract: A bobbin structure with winding grooves for adjusting coupling at least includes: a bobbin body, a hole provided in the bobbin body for allowing magnetic wires to pass through, and at least three separated winding grooves with different lengths provided around the outer peripheral side of the hole. The primary winding (or the secondary winding) of the coils of a transformer is selectively wound into one of the winding groove, while the secondary windings (or the primary windings) are wound into the rest of the winding grooves. By altering the numbers of turns of the secondary windings (or the primary windings) distributed in the winding grooves, different coupling effects can be achieved with respect to the primary winding (or the secondary winding). As a result, the transformer leakage inductance and the output impedance can be conveniently adjusted. The design of multiple grooves also reduces the stray capacitances of the windings, thereby increasing the bandwidth of the transformer.

Abstract: An improved structure of a transformer includes a bobbin covering at least a portion of a magnetic core set which has a magnetic loop passing through the bobbin, wherein winding grooves and at least one connecting portion extending sideways are provided on the outer peripheral side of the bobbin, and a plurality of notches with lateral openings are provided on the connecting portion. Coils are wound in the winding grooves of the bobbin. The coils have at least a plurality of line ends, each line end passing through a different notch. One positioning pin is embedded in each of the winding grooves near the lateral opening. The positioning pins hold the respective line ends in place by pressing against them. A casing is fitted on the outer peripheral side of the coils to create separation between the coils and the magnetic core set. The casing is provided with a hollow opening such that the outer peripheral side of the coils facing the airflow is exposed to improve the overall heat dissipating efficiency.

Abstract: An improved structure of transformer includes a lead frame main body (1), a lead frame cover (2), a trouser-like flap (3), and two iron cores (4) where the lead frame main body (1) has a penetration hole (11) with a bobbin (12) formed at the circumference there around. The trouser-like flap (3) being made of metal has a hollow part (31) for slipping on a bobbin (121) of the lead frame main body (1) also includes horizontally stretched thigh parts (32), (33). The outer circumference of the trouser-like flap (3) is furnished with a primary winding (123). The lead frame cover (2) being a sheet-shaped body has a hollow hole (21) furnished at the center thereof. On the inner-side surface, each of the two iron core (4) has a main core part (41) capable of stretching through the penetration hole (11) of the lead frame main body (1) where the main core part (41) has a containing circumferential trench (43) capable of containing the lead frame main body (1).