Abstract: A bi-directional low capacitance TVS using a PIN or NIP diode is disclosed. Bi-directional low capacitance TVS protection circuit (1000) consists of two pairs of TVS diodes (1001), (1003) and LC PIN or NIP diodes (1002), (1004). Diodes (1003) and (1004) are in parallel and in opposite direction from a first series of TVS and LC diode pair. This circuit provides transient protection in both directions for a bi-directional low capacitance TVS.

Abstract: An adaptive leading edge blanking circuit in which the leading edge blanking time is reduced at low to very low power levels of an SMPS, but is substantially constant at medium to high power levels. Adapted leading edge blanking time maybe provided by modifying a conventional leading edge blanking timer in which a fixed voltage reference source is replaced with a variable voltage reference source, the variable voltage reference being dependent upon power requirements on a secondary side of the SMPS.

Abstract: The present invention provides an inverter controller comprising a drive circuit that generates a plurality of switch drive signals for inverter applications. In some exemplary embodiments, the drive circuit operates by reversing the command level of an error signal. In other embodiments, the drive circuit operates by using a half period of a sawtooth signal. In still other embodiments, the drive circuit operates by using a double period opposite shifting pulses method. The present invention also provides a PWM signal generator circuit that generates periodic PWM switch drive signals symmetrical to the minimum or maximum of a sawtooth waveform.

Abstract: The Invention is a 360 watt bench has an exceptionally wide output range that allows it to replace up to four conventional units. The output voltage can be manually adjusted with coarse and fine controls from zero to 75 volts. At the low voltage end, 60 amps of output current is available up to 6 volts, and beyond that, the power is limited to 400 watts. The power supply can operate in constant voltage or constant current mode, and a current setting control can adjust the maximum current down to zero from the value set by the automatic power limit. The principle may be applied to any power level and combination of voltage and current, and any method of manual or programming control.

Abstract: A fly-back type synchronous rectifying switching power supply device in which a rectifying element is turned off before the main switch is turned on even when the on-time of a main switch element is lengthened due to sudden variation of a load. The synchronous rectifying switching power supply device is equipped with a synchronous rectifying element connected to a secondary winding of a transformer in series and driving means including an auxiliary winding for turning on the synchronous rectifying element complementarily with a main switch element between output terminals. A transistor serving as interrupting means for turning off the synchronous rectifying element is provided between the gate and source of the synchronous rectifying element.

Abstract: Open ends of a number of secondary windings are fixed by winding them around a film projection portion formed by cutting and raising insulating films provided between the layers of the secondary windings. This eliminates the requirement that a number of terminals on a bobbin corresponding to the secondary windings be fixed by winding them around the film projection portion, whereby the number of terminals provided on the bobbin can be reduced, and the bobbin can be made smaller in size.

Abstract: A dc-dc converter is disclosed comprising an active clamp topology, including an active clamp resonant transition system to provide substantially zero or reduced voltage for turn-on of the primary switch. The resonant transition system includes an inductor in series with the primary winding of the power transformer and a clamp diode that operate cooperatively to turn on the primary switch with reduced voltage. A second diode is included in series with a balancing resistor to discharge a snubber capacitor with improved efficiency. The addition of these circuit components provides low switching losses and low component stresses in the overall design.

Abstract: The present invention is to provide a switching power supply device for preventing the change of characteristic of the line filter due to filler such as resin which covers the circuits.

Abstract: A device for protecting I/O lines using PIN or NIP low capacitance transient voltage suppressors and steering diodes are disclosed. In an exemplary embodiment, a two (2) terminal device with a unidirectional low capacitance TVS diode (1101) and an anti-parallel LC PIN or NIP diode (1102) is disclosed. To provide for a low capacitance TVS with a forward conducting low-voltage characteristic, the LC PIN or NIP diode is placed anti-parallel to the unidirectional low capacitance TVS. This LC PIN or NIP diode must also have a reverse blocking voltage greater than the avalanche breakdown p-n junction voltage (V(BR)) of the unidirectional TVS.

Abstract: The invention describes a system for electrical transmission in the field of garments and a corresponding transmitter for this. Electrical circuits in garments are coupled, preferably inductively in a wireless manner with electrical devices and/or electrical circuits in other garments, wherein electrical energy is transmitted via the coupling. Energy transmission in both directions is preferably possible, wherein a distributed system results with sources and devices that can be coupled with each other. The efficiency of the inductive energy transmission is increased by regulation of the frequency, preferably using resonance. In addition, means for information transmission are proposed.

Abstract: A DC-DC power converter has a transformer with a primary side and secondary side. A first power transistor is coupled between a first end of a first winding of the secondary side and a ground terminal. A second power transistor is coupled between a second end of the first winding and the ground terminal. A first driver transistor is coupled to a gate of the first power transistor, and a second driver transistor is coupled to a gate of the second power transistor. A separate driver winding taken off the secondary side of the transformer controls the gates of the first and second driver transistors. First and second inductors are coupled between the opposite ends of the first winding and an output of the power supply. First and second resistors are coupled between the gates of the first and second driver transistors and the ground terminal, respectively.

Abstract: A method for current limiting of an output of a DC-to-DC converter begins by determining a current loading duty cycle of the output of the DC-to-DC converter (i.e., the present duty cycle given the loading of on the output). The processing then continues by comparing the current loading duty cycle with a zero loading duty cycle of the output (i.e., the duty cycle when the output has no load). The processing continues by limiting duty cycle of the output to the zero loading duty cycle plus a duty cycle loading offset when the current loading duty cycle exceeds the zero loading duty cycle plus the duty cycle loading offset.

Abstract: The present invention relates to a bidirectional flyback switch mode power supply (SMPS), such as a bidirectional flyback converter, and a method for operating it. The SMPS comprises a transformer having primary and secondary windings inductively coupled together, said primary winding being coupled to a voltage input of the converter and said secondary winding being coupled to a voltage output of the converter; a primary control unit comprising a primary switch arranged in series with the primary winding and a secondary control unit comprising a secondary switch arranged in series with the secondary winding. The primary control unit is adapted to compensate input voltage variations, and the secondary control unit is adapted to provide a controlled output power on the secondary side.

Abstract: The invention concerns a direct energy-transfer converter of the AC/AC or DC/DC type, including a self-regulated synchronous rectifier, in which the rectifier switches are controlled through one or more transformer windings. The converter includes a primary stage with at least one primary winding of a transformer and at least one controlled switch, with a secondary stage having at least one secondary winding (10) of the transformer, and a synchronous rectifier (1) with at least a first switch (20) which is self-regulated and conducting during the conducting phase of the controlled switch of the primary stage, known as the direct energy-transfer stage, and at least one secondary switch (30) which is self-regulated and conducting during the non-conducting phase of the controlled switch of the primary stage, known as the freewheel phase, and an output filter (5).

Abstract: A converter includes a transformer having a primary winding, a secondary winding and an auxiliary winding, a first switching device for connecting an input voltage to the primary winding of the transformer, an output circuit connected to the secondary winding, a controller, and an integrated active clamp and primary bias circuit. The integrated active clamp and primary bias circuit includes the auxiliary winding and a second switch providing a bias voltage to the controller to alternately operate the first and second switches between conductive and non-conductive states. When the first switch is conductive the second switch is nonconducting and power is transferred from the primary winding to the output circuit via the secondary winding and from the auxiliary winding to the controller. When the first switch is nonconducting, the second switch is conducting and the voltage across the primary winding is clamped.

Abstract: A DC-DC converter achieves a high level of a signal superimposed in an AC manner onto the output of an insulator such as a photocoupler, and there are very few limitations in the aspects of constant design, phase correction, starting characteristics, and short-circuit protection. A secondary-side control circuit detects an output voltage, and feeds back a control signal to a drive control circuit on the primary side via a photocoupler. The photocoupler insulates the primary side of a DC-DC converter from the secondary side thereof, wherein the control signal output from the secondary-side control circuit is transmitted to the primary side. The output signal of an auxiliary power-supply circuit is superimposed in an AC manner onto the control signal via a coupling capacitor. The drive control circuit has a configuration in which a pulse control signal is applied to a switching element in order to stabilize the output voltage of a secondary-side circuit on the basis of the control signal.

Abstract: Methods and systems of monitoring voltage input to network elements are provided. One method includes receiving an input voltage for a line-powered network element, applying the input voltage across a primary winding of a flyback power converter during an on-time of a primary switch, and transferring the input voltage from the primary winding to a secondary winding of the flyback power converter during an off-time of the primary switch. The method further includes sensing the voltage of the secondary winding during the on-time of the primary switch; and drawing minimal current from the flyback power converter.

Abstract: An electrical circuit for providing a temperature compensated feedback signal includes a first electrical component and a first amplifier. The first electrical component exhibits a first temperature variable impedance and is positioned in thermal contact with a first switch having a second temperature variable impedance. The first amplifier includes an input electrically coupled to the first switch and an output electrically coupled to an input of the first electrical component. The first amplifier amplifies the signal produced across the first switch when the first switch is conducting and the first electrical, component attenuates the amplified signal provided by the first amplifier as a function of a temperature of the first electrical component. The attenuated amplified signal is provided at an output of the first electrical component to provide a temperature compensated feedback signal.

Abstract: A surge voltage detection circuit compares a stipulated voltage VS with the drain voltage of a switching element, the drain voltage being applied by a smoothing capacitor. The comparison result is supplied to a switching control circuit. If the drain voltage of the switching element is higher than the stipulated voltage VS, the switching control circuit inhibits the operation of the switching element. As a result, no switching operation is started, and the drain voltage of the switching element does not exceed the breakdown voltage of the element.

Abstract: The present invention proposes an improved circuit design and configuration of a DC-DC converter with resonant reset. In this present invention, the active resonant snubber in parallel to a primary winding of a transformer of a DC-DC converter for resetting the transformer includes a resonant capacitor, an active switch connected to the resonant capacitor in series, an auxiliary diode coupled across the active switch in parallel, and an auxiliary winding coupled with the transformer. When a main switch of the DC-DC converter is turned off, the auxiliary winding turns on the active switch, and then the transformer is reset by a resonance between a magnetizing inductor of the transformer and the resonant capacitor.

Abstract: A switching power supply causes fewer losses, being capable of suppressing surges generated at a switching element, and providing improved conduction noise characteristics. The present invention is a switching power supply, wherein voltages and currents are varied by turning said switching element on and off to convert input voltages into output voltages, comprising a distributed parameter line with a line length of about n 4 (n is an integer of one or more) of a wavelength peculiar to a potential point at said fluctuating potential point in said switching power supply.

Abstract: A DC—DC converter is disclosed comprising an active clamp topology, including an active clamp resonant transition system to provide substantially zero or reduced voltage for turn-on of the primary switch. The resonant transition system includes an inductor in series with the primary winding of the power transformer and a clamp diode that operate cooperatively to turn on the primary switch with reduced voltage. The addition of these circuit components provides lower switching losses and lower component stresses in the overall design.

Abstract: A system and method of creating a pulse train signal of a pulse width modulator whose fundamental frequency is time-varying is disclosed. The electrical system includes a pulse width modulator which provides a pulse train signal. The system also includes a power source connected to the pulse width generator. The system further includes a binary counter having an input and a plurality of outputs, wherein the pulse train signal generated by the pulse width modulator is operatively coupled to the input of the binary counter. A plurality of resistors are operatively coupled to the plurality of outputs of the binary counter and operatively coupled to a node. A timing resistor is operatively coupled between a first voltage potential and the node, while a timing capacitor is operatively coupled between the node and a second voltage potential. The node is operatively coupled to an input of the pulse width modulator.

Abstract: A programmable AC/DC power converter receives a plurality of input voltages and outputs a single voltage from an input voltage system. A transformer receives the single voltage. One of the plurality of input voltages is provided at a center tap of a secondary winding of the transformer. A transformed voltage is output. A rectifier receives the transformed voltage and outputs a DC voltage. A buck regulator receives a DC voltage, creates a regulated voltage, and outputs the regulated voltage and a regulated current to a portable appliance. A error correction system receives a programming signal and regulated signals and verifies that the regulated signal to programming signal ratio is within an acceptable range.

Abstract: A voltage converter comprises two input terminals between which at least a current limiter, an electronic switch controlled by a control device in synchronization with the supply voltage and a storage capacitor are disposed, and whose two output terminals are taken from the storage capacitor, wherein the current limiter is formed by at least the primary of a transformer whose secondary supplies a rectifier whose output terminals are connected to the output terminals of the converter.

Abstract: In a power supply apparatus having voltage doubler rectifier circuit (5) connected to secondary winding (1B) of transformer (1), diode (13) is connected between transistor (3) and primary winding (1A) of transformer (1). By detecting an AC voltage at a junction point between primary winding (1A) of transformer (1) and diode (13) thereby performing over-voltage protection, the difference between the maximum operating voltage and the no-load operating voltage is decreased and the voltage during no-load operation is lowered and thus small-sized power supply apparatus and peripheral equipment can be provided.

Abstract: A display apparatus includes a power supply comprising a commercial AC power supplying part, a transformer having a primary coil and a secondary coil and supplying an AC voltage to driving circuits, and a feedback voltage sensing part sensing a load of the secondary coil. The power supply further includes a power mode information part outputting information for determining a normal mode or a power saving mode according to an input of a synchronous signal. The power supply also includes a power driving part including a power driver generating a power regulating signal according to a synchronous signal on the basis of a feedback voltage sensed by the feedback voltage sensing part at the normal mode, and an idle power driver generating a power saving voltage on the basis of a synchronous signal which is made by synthesizing different frequency signals at the power saving mode; an idle switching part turning on/off the idle power driver.

Abstract: A DC-DC converter is disclosed comprising an active clamp topology, including an active clamp resonant transition system to provide substantially zero or reduced voltage for turn-on of the primary switch. The resonant transition system includes an inductor in series with the primary winding of the power transformer and a clamp diode that operate cooperatively to turn on the primary switch with reduced voltage. The addition of these circuit components provides lower switching losses and lower component stresses in the overall design.

Abstract: A transformer isolated gate driver for realizing the driving of a power switch (a MOSFET) includes a PWM driver, an input capacitor, a transformer, an output diode, a active switch (a small power MOSFET) having a gate and a source connected to the first and second terminals of the secondary winding of the transformer respectively, an output capacitor connected to one of the first terminal of the transformer and a drain of the active switch in series, and a series connected circuit having the first and second terminals of the transformer, the output capacitor, the output diode, and the active switch. The charges across an equivalent input capacitor of the power switch are discharged through the series connected circuit. When the PWM signal is pulled to zero from normal operation, the driving signal on the power switch is kept zero also.

Abstract: A circuit provides a secondary output voltage from an input voltage. The circuit includes power supply circuitry for creating an unregulated DC bus voltage line and a regulator circuit connected to the DC bus voltage line for controlling a first switch in series with a transformer winding. The control circuit samples an output voltage to control the output voltage by cycling the first switch. The circuit further includes a pulse generator circuit connected to the regulator circuit for controlling start and stop cycles of the regulator circuit and a comparator circuit connected to the pulse generator circuit for monitoring the secondary output voltage and for disabling the pulse generator circuit during normal operation of the power supply circuit.

Abstract: A constant current output control method and device for a switching power supply circuit for constant current output control of an output current I2o of a rectifying smoothing.

Abstract: A power converter module includes a power transformer, a first power switch, and an active snubber circuit for recovering surge energy. The power transformer has a primary winding and a secondary winding adapted to be coupled electrically to a load. The primary winding has first and second terminals connected electrically and respectively to first and second nodes. The first power switch has a first switch terminal connected electrically to the second node, and a second switch terminal connected electrically to a third node. The first and third nodes are adapted to be coupled electrically to a power source. The active snubber circuit includes a snubber diode, a snubber capacitor, a snubber transformer, and a second power switch.

Abstract: A converter mounting comprises a memory coil inductance (8), a memory primary capacitor (3) mounted upstream of said coil inductance, and a memory secondary capacitor (4), in particular, a piezoelectric actuator, mounted downstream of said coil inductance. Through control of a primary circuit element (12) and of a secondary circuit element (14), the energy of the memory primary capacitor (3) can be transferred to the memory secondary capacitor (4) and recovered.

Abstract: In a DC/DC converter using an insulating transformer Tr having a center tap on the secondary side, an input choke coil L1 and an output choke coil L3 are integrated with the insulating transformer Tr, a primary coil (number of turns: 2N) and a secondary coil (number of turns: n+n) of the transformer, the input choke coil L1 (number of turns: 2N), and the output choke coil L3 (number of turns: n) are wound around a common core (magnetic core), and the coils are arranged in directions of canceling DC fluxes generated by the coils, so that the DC bias magnetization is considerably reduced.

Abstract: The invention concerns a direct energy-transfer converter of the AC/AC or DC/DC type, including a self-regulated synchronous rectifier, in which the rectifier switches are controlled through one or more transformer windings. The converter includes a primary stage with at least one primary winding of a transformer and at least one controlled switch, with a secondary stage having at least one secondary winding (10) of the transformer, and a synchronous rectifier (1) with at least a first switch (20) which is self-regulated and conducting during the conducting phase of the controlled switch of the primary stage, known as the direct energy-transfer stage, and at least one secondary switch (30) which is self-regulated and conducting during the non-conducting phase of the controlled switch of the primary stage, known as the freewheel phase, and an output filter (5).

Abstract: In accordance with an embodiment of the invention, a switching mode power supply includes a rectifier configured to convert AC power to a first DC power, an output unit configured to convert the first DC power to a second DC power under the control of a first switch, and a pulse width modulation generator coupled to control the first switch. The pulse width modulation generator has a regulator configured to regulate the first DC power. The regulated first DC power powers the pulse width modulation generator. The regulator includes a second switch coupled to control a transmitter so that when the second switch is in a first state the transmitter transmits the first DC power to a capacitor to charge the capacitor, and when the switch is in a second state the transmitter does not transmit the first DC power to the capacitor to thereby allow the charge in the capacitor to reduce.

Abstract: The invention relates to a circuit arrangement with a regulating circuit which is particularly used for regulating a resonant converter having a plurality of outputs.

Abstract: There is provided an output voltage stabilizer for stabilizing an output voltage of a switching mode power supply by elimination power bounce appearing on the output voltage of the switching mode power supply. The output voltage stabilizer mainly includes a voltage comparator that compares a DC voltage with a reference voltage and in response thereto generates an output signal, and a control switch that is biased according to the output signal of the voltage comparator and provides the power supply a drive signal to stabilize an output voltage of the power supply according to an on/off state of the control switch.

Abstract: The present invention relates to an isolated-type switching power supply apparatus, which includes a power supply, a transformer being connected to said power supply, a switching element for switching an electric current going through a primary coil of the transformer so that energy generated on the primary side of the transformer is sent to the secondary side in accordance with the operation of the switching element. The present invention has a modulating circuit for modulating an output on the secondary side of said transformer, a transmitting rout for transmitting an output of the modulating circuit to the primary side of the transformer, a demodulating circuit for demodulating the output transferred through the transferring rout; and the controlling circuit controls the switching element in accordance with an output of the demodulating circuit and the controlling circuit is disposed on the primary side of the transformer.

Abstract: Disclosed is an electromagnetic circuit wherein coils are wound in a forward (clockwise) direction and in a reverse (counterclockwise) direction and semiconductor switches are mounted in front of the respective coils so that a non-induction line becomes a polarity-converting point of an alternating magnetic flux by controlling currents. Accordingly, a mechanical dynamic power of a high torque can be obtained by electrical energy.

Abstract: Provided is a DC-DC converter which is capable of obtaining a stable output irrespective of the fluctuation of the power source voltage and ensuring the reliability of a device. The DC-DC converter configured such that a current of a primary coil of a boosting transformer supplied from a power source unit is intermittently caused to flow through the converter by a power MOS-FET and an ignition capacitor is charged with electricity through a rectifier diode using the voltage of a secondary coil of the boosting transformer boosted by the flyback voltage of a coil, includes a current detecting circuit for detecting a drain current of the power MOS-FET, and a control circuit for, when the drain current detected by the current detecting circuit exceeds a predetermined threshold, turning off the power MOS-FET for a fixed period of time, and then turning on the power MOS-FET again.

Abstract: For use in a power converter having a power switch and a synchronous rectifier device coupled between input and output thereof, a control circuit, method of disabling a synchronous rectifier device and power converter employing the control circuit and method. In one embodiment, the control circuit includes a synchronous rectifier controller, coupled to the output of the converter and the synchronous rectifier device, that senses time derivative of the output voltage and disables the synchronous rectifier when derivative is negative and greater than a predetermined magnitude.

Abstract: A DC-to-DC converter having an input voltage and an output voltage, which includes a circuit topology such that, in operation, the input and output voltages have the same polarity, and that a magnitude of a ratio of the input voltage to the output voltage of the DC-to-DC converter is capable of being equal to, greater than, or less than one. The circuit topology is also such that a same at least one capacitor and alternative coils of a two-coil inductor are employed in a primary and a secondary circuit loop of the DC-to-DC converter. The primary and secondary circuit loops are not electrically isolated.

Abstract: An overcurrent output protector is electrically connected to a constant-voltage switching power supply provided with a switching transistor which converts a DC voltage obtained by smoothing an AC voltage supplied from an AC power source into a cyclic pulse signal. In the overcurrent output protector, duty ratio monitor judges whether an ON duty ratio of the cyclic pulse signal is a predetermined ratio or more. A deactivator turns off the switching transistor in a case where the duty ratio monitor judges that the ON duty ratio is the predetermined ratio or more.

Abstract: The number of layers of a secondary winding of a flyback transformer for use in a PWM controlled high-tension voltage generator is increased to six or higher. The distributed capacitance of the flyback transformer is thus decreased, the frequency of ringing is increased, and the pulse width of a flyback pulse is narrowed. The timing of the on-operation of a control FET is expedited, and the input current to the flyback transformer is lowered. A compact and power-saving flyback transformer thus results.

Abstract: A series circuit of a primary winding 1 A of a transformer 1 and a switching element 2 is coupled to a DC source 3 and a voltage induced in a secondary winding 1B of the transformer 1 according to switching operation of the switching element 2 is rectified and smoothed by a rectifier smoothing circuit 9. Further, a Zener diode 21 is coupled across the switching element 2 with reverse polarity to the switching element 2. The Zener diode 21 may be coupled across a rectifier diode 5 which conducts during the ON period of the switching element 2.

Abstract: A power supply apparatus having an AC power supply, a transformer, a switching element and a control circuit for controlling an operation of the switching element: where an electrical current is supplied to the primary side of the transformer intermittently when a main unit of an electrical appliance to which the power supply apparatus is applied is in a standby mode so that unnecessary power consumption is reduced. Further, a capacitance is provided between the AC power supply and the control circuit instead of the conventional initializing resistance and the control circuit is driven using an electrical current going through a reactance component of the capacitor, so that the energy loss is not caused any more by the initializing resistance.

Abstract: A switch-mode power converter that powers the fan or blower unit in a communication system is used to suppress the audio band noise, thereby eliminating any need for additional passive or active filters used in the prior art. The frequency response of a switch-mode DC/DC converter is set by a control loop. By modifying the feedback amplifier compensation network in the control loop such that the frequency control loop bandwidth of the converter is substantially less than the AC load of the fans or blowers, the invention eliminates the need for additional filtering beyond that inherent in the power converter.

Abstract: The object of the present invention is to provide a DC/DC converter and a method for controlling the DC/DC converter whereby losses under light loads are reduced.

Abstract: A charging device capable of dynamically adjusting a charging power. The charging device has elements as follows. A DC-DC converter power stage is used for supplying a charging current to the rechargeable battery. A current error amplifier is used for setting a charging current adjustment signal, being fed to the DC-DC converter power stage for adjusting the charging current. A first current detecting device is used for setting the charging current signal being fed to the current error amplifier. Meanwhile, the charging current is outputted to the rechargeable battery to charge the rechargeable battery. A current detecting/comparating device is used for feedback and outputting the charge current operation signal based upon the work current and a calculated charge current signal. The charging device dynamically adjusts the charging power to increase the utility of the output power of the external power source and reduce the charging time.