Delta Electronics, Inc.

Shih-Hsien Chang

Hsin-Wei Tsai

Yi-Lin Chen

Bou-Jun Zung

Po-Nien Ko

Chia-Hung Pai

Zhi-Liang Zhang

Ming-Chih Hsieh

Ching-Hsien Teng

Tzu-Yang Liu

Ching-Hsing Tien

Jian-Feng Tsai

Hong-Chih Lee

Yao-Tien Huang

Chih-Hsuan Lee

Chih-Hung Yen

A resonant transformer and resonant converter are disclosed. The resonant transformer includes a first bobbin, a first primary winding coil, plural first secondary winding coils, a second bobbin, a second primary winding coil, plural second secondary winding coils and a magnetic core assembly. The first bobbin includes a first winding section and plural single-trough second winding sections. Plural pins are arranged at the first winding section. The first primary winding coil is wound around the first winding section and connected with the pins. The first secondary winding coils are wound around respective single-trough second winding sections. The second bobbin includes a third winding section and plural single-trough fourth winding sections. The second primary winding coil are wound around the third winding section and connected with the pins at the first winding section of the first bobbin. The second secondary winding coils are wound around respective single-trough fourth winding sections.

Resonant transformer and resonant converter employing same

A LED backlight module includes a substrate, a heat-dissipating plate, a LED string and a backlight driving circuit. The LED string includes plural LEDs. The LED string further includes a positive driving terminal, a negative driving terminal and a connecting terminal. A positive output terminal, a negative output terminal and a zero voltage terminal of the backlight driving circuit are respectively connected with the positive driving terminal, the negative driving terminal and the heat-dissipating plate, so that a positive driving voltage and a negative driving voltage are generated by the backlight driving circuit to drive illumination of the LED string. A first number of LEDs of the LED string are electrically connected between the connecting terminal and the positive driving terminal. A second number of LEDs of the LED string are electrically connected between the connecting terminal and the negative driving terminal.

LED backlight module and backlight driving circuit

A current-sharing supply circuit includes a current providing circuit, a first output rectifier circuit, a second output rectifier circuit, a first current-sharing transformer, a second current-sharing transformer, a first current-sharing circuit and a second current-sharing circuit. By adjusting the equivalent impedance values of the first current-sharing circuit, the second current-sharing circuit, the primary winding coil of the first current-sharing transformer and the primary winding coil of the second current-sharing transformer, the first output current and the second output current are substantially identical.

Current-sharing supply circuit for driving multiple sets of DC loads

A power supply circuit for receiving an input voltage to drive a plurality of loads is disclosed. The power supply circuit comprises a plurality of switch circuits, a plurality of power conversion circuits and a phase delay circuit. The plurality of switch circuits are connected with the plurality of loads, respectively. The plurality of power conversion circuits are connected with the plurality of loads and the plurality of switch circuits, respectively, for converting the input voltage into a plurality of driving voltages and transmitting the plurality of driving voltages to the plurality of loads, respectively, when the plurality of switch circuits are conducted. The phase delay circuit is connected with the plurality of switch circuits and a system circuit for generating a plurality of delay signals in response to a switch signal from the system circuit and transmitting the plurality of delay signals to control terminals of the plurality of switch circuits, respectively, so as to make the plurality of switch circuits be conducted or shut off. The plurality of delay signals are converted into an enabling status from a disabling status at different time points so that the plurality of switch circuits are conducted at different time points.

Power supply circuit and control method thereof

A transformer includes a bobbin assembly, a primary winding coil, a first secondary winding coil, a second secondary winding coil, and a magnetic core assembly. The bobbin assembly includes a primary winding part, a first secondary winding part, a second secondary winding part and a channel. A first opening is formed in a bottom surface of the bobbin assembly and communicates with the channel. The primary winding coil is wound around the primary winding part. The first secondary winding coil is wound around the first secondary winding part. The second secondary winding coil is wound around the second secondary winding part. The magnetic core assembly is partially embedded into the channel of the bobbin assembly, and includes a first magnetic part and a second magnetic part. The second magnetic part includes a first extension post, and the first extension post is inserted into the first opening of the bobbin assembly.

Transformer having leakage inductance

A multi-loop power factor correction circuit includes a first rectifier circuit, an integrated multi-inductor magnetic member, plural switching circuits, plural rectifying elements, and a power factor correction controlling circuit. The integrated multi-inductor magnetic member includes a first slab, a second slab, a middle post, plural lateral posts, and plural winding coil assemblies. The winding coil assemblies are wound around respective lateral posts to form at least a first inductor and a second inductor. The magnetic flux cross-section area of the middle post is smaller than the sum of the magnetic flux cross-section areas of the lateral posts. The switching circuits are alternately conducted, so that the distribution of an input AC current is similar to the waveform of the input AC voltage.

Integrated multi-inductor magnetic member and multi-loop power factor correction circuit having same

A power conversion circuit for decentralizing input current includes a capacitor, a first inductor, a first switching circuit, a first discharging circuit, a second inductor, a second switching circuit, a second discharging circuit, and a control circuit. Under control of the control circuit, the first switching circuit and the second switching circuit are alternately conducted, and the second switching circuit is successively conducted when the first switching circuit is shut off.

Power conversion circuit for decentralizing input current

A two-stage switching power supply includes a first-stage power circuit, a second-stage power circuit, an output detecting circuit and a power control unit. The first-stage power circuit includes a first switching circuit. By conducting or shutting off the first switching circuit, an input voltage is converted into a bus voltage. The second-stage power circuit includes a second switching circuit. By conducting or shutting off the second switching circuit, the bus voltage is converted into an output voltage. The output detecting circuit generates an output detecting signal according to the output voltage. The power control unit controls operations of the first and second switching circuits according to the output detecting signal. A first-stage voltage gain value of the first-stage power circuit and a second-stage voltage gain value of the second-stage power circuit are altered with the output detecting signal, so that the output voltage is maintained at a rated value.

Two-stage switching power supply

An illumination driving system includes a control unit and at least one base. The control unit includes a first converter and a brightness-adjustable circuit. An input AC voltage is converted into a regulated DC voltage by the first converter. The brightness-adjustable circuit is connected to the first converter. The base is separated from the control unit for supporting the at least one light-emitting device. The base includes a second converter. The second converter is connected with the first converter and the light-emitting device for converting the regulated DC voltage into an output voltage. The light-emitting device is driven to illuminate by the output voltage. The brightness-adjustable circuit generates a brightness adjusting signal to the first converter. The magnitude of the regulated DC voltage is adjusted according to the brightness adjusting signal, thereby adjusting the brightness value of at least one light-emitting device.

Brightness-adjustable illumination driving system

A light source driving circuit includes a transformer, a switching circuit, a control circuit, a brightness adjusting circuit and an isolator circuit. The brightness adjusting circuit is connected to a secondary winding assembly of the transformer and the light-emitting element for detecting an output voltage and/or an output current and generating a control signal according to the brightness adjusting signal. The isolator circuit is used for isolating the primary winding assembly of the transformer from the brightness adjusting circuit. The isolator circuit generates a feedback current according to the control signal. According to the feedback current, the switching circuit is controlled by the control circuit. As a status of the brightness adjusting signal is changed, a status of the control signal is changed and a time period of changing the status of the control signal is longer than a time period of changing the status of the brightness adjusting signal.

Light source driving circuit

A current-sharing transformer includes a magnetic core assembly, a primary winding coil and multiple secondary winding coils. The magnetic core assembly includes a main magnetic post and multiple minor magnetic posts. The primary winding coil is wound around the main magnetic post. The secondary winding coils wound around respective minor magnetic posts. The secondary winding coils are connected to respective DC loads through respective rectifier circuits. The magnetic paths between respective minor magnetic posts and the main magnetic post are equal, so that the magnitudes of currents passing through the DC loads are balanced by the current-sharing transformer.

Current-sharing transformer and power supply circuit having such current-sharing transformer

A magnetic element includes a conducting winding structure, first and second magnetic parts, and first and second side posts. The first and second magnetic parts have first and second central posts that are aligned with each other. The first side post is disposed on an edge of the first or second magnetic part. The second side post is disposed on another edge of the first or second magnetic part where no side post is disposed or the first side post is not aligned with. The conducting winding structure is sandwiched between the first and second magnetic parts. The first and second side posts are aligned with corresponding edges wherein no side post is disposed. Consequently, the overall height of the first and second central post is less than the height of the first or second side post and an air gap is defined between the first and second central post.

Magnetic element

A power supply for supplying power to a lamp with functions of dimming, over-current protection, over-voltage protection, arcing protection, and low-temperature start-up is provided. When frequency of the output current exceeds a predetermined value, the power supply is turned off to accomplish a dimming goal and extend lifetime of the lamp. When abnormal statuses such as open-circuited status, short-circuited status, or arcing status occur, a surge current induced by the abnormal statuses may be eliminated to prevent the power supply from being damaged. A high-frequency current detection circuit is configured to detect whether a current supplied to the high-voltage load is a high-frequency current to prevent damage to the electronic elements in the high-voltage load. A current adjusting circuit is configured to adjust an alternating current outputted to a lamp set in response to an environment temperature to supply an adequate alternating current at a low temperature for starting the lamp set.

Power supply for supplying power to a lamp

A switching power conversion circuit includes a power circuit, a feedback circuit and a control circuit. The power circuit includes a switching circuit and a first magnetic element. The first magnetic element generates a magnetic flux change by alternately conducting or shutting off the switching circuit, so that an input voltage is converted into the output voltage by the power circuit. The feedback circuit generates a feedback signal according to the output voltage. The control circuit is used for controlling an on duration and an off duration of the switching circuit, thereby maintaining the output voltage at a rated voltage. The off duration of the switching circuit is maintained at a constant interval under control of the control circuit. The on duration of the switching circuit is adjusted to be a specified interval smaller than a maximum on duration according to the magnitude of the input voltage.

Switching power conversion circuit

A multi-output power conversion circuit is provided for converting an input voltage into a standby voltage and a first output voltage. The multi-output power conversion circuit includes a transformer, a power switching circuit, a first rectifier-filter circuit, a second rectifier-filter circuit, a first switching circuit, a voltage-adjusting circuit, a feedback circuit and a power control circuit. The feedback circuit is connected to the first rectifier-filter circuit, the second rectifier-filter circuit and the system circuit. The feedback circuit generates a feedback voltage according to a power-status signal issued by the system circuit. The power control circuit is interconnected between the power switching circuit and the feedback circuit for controlling on/off statuses of the power switching circuit according to the feedback voltage. The feedback circuit generates the feedback voltage according to the power-status signal and selectively according to the first DC voltage or the second DC voltage.

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Taoyuan Hsien, Taiwan

Shih-Hsien Chang