Abstract: A synthetic ripple regulator for a DC-DC converter generates an auxiliary voltage waveform that effectively replicates the waveform ripple current through an output inductor, and uses the auxiliary voltage waveform to control toggling of a hysteretic comparator. In a non-limiting implementation, a transconductance amplifier monitors the voltage across the inductor, and supplies an inductor voltage-representative current to a ripple waveform capacitor, so as to produce the auxiliary voltage waveform. Using the replicated inductor current for ripple regulation results in low output ripple, input voltage feed forward, and simplified compensation.

Abstract: A power switching stage architecture for a buck topology-based, DC-DC converter includes an upper power switching N-channel device FET integrated in the same semiconductor circuit chip with the switching driver, while a lower power switching is also an N-channel FET, but is external to the driver chip. Either of the two power switching FETs may be configured to include a pilot FET cell, to facilitate current sensing for the controller.

Abstract: A DC-to-DC converter includes one or more power switches, a pulse width modulation circuit for generating control pulses for the power switches, and an output inductor connected to the power switches. A thermally compensated current sensor is connected to an intrinsic current sensing element exhibiting a temperature-based parameter non-linearity. The thermally compensated current sensor has a temperature coefficient that substantially matches a temperature coefficient of an intrinsic power converter element used to measure current flow, thus linearizing the current measurement. Also, a current feedback loop circuit cooperates with the pulse width modulation circuit to control the power switches responsive to the thermally compensated current sensor.

Abstract: An output stage for a class D amplifier reduces distortion and EMI, and greatly improves the efficiency. The output stage employs a combination of techniques including a soft switching network, multiple output inductors and beads to achieve, a high power full range class D amplifier that is complies with all FCC and CE specifications with greater than 90% efficiency at ⅓ power.

Abstract: A multi-phase DC/DC converter having an output voltage and including a plurality of converter channels. Each converter channel includes a converter channel input and a converter channel output. Each converter channel is configured for generating a converter channel current and for adjusting said converter channel current in response to a control signal electrically connected to each converter channel input. A control circuit generates an error signal representative of a comparison of the converter output voltage to a reference voltage. The control circuit includes a plurality of control circuit channels, each of which correspond to a converter channel. Each control circuit channel generates a channel current signal representative of a corresponding converter channel current, and generates a differential channel current signal representative of a comparison of the channel current signal to an average current signal.

Abstract: A DC to DC buck pulse width modulator converter circuit includes an input, a high side output and a low side output. A high side switch is electrically connected between a common output node and a voltage supply, and controls a flow of current therethrough dependent upon the high side output. A low side switch is electrically connected between the common output node and ground, and controls a flow of current therethrough dependent upon the low side output. A virtual ground amplifier includes a second input electrically connected to ground. A current feedback resistor is electrically connected intermediate the common output node and a first input of the virtual ground amplifier. A variable impedance component is electrically connected to an output of the virtual ground amplifier and to the first input of the virtual ground amplifier. The impedance of the variable impedance component is varied dependent upon the output of the virtual ground amplifier.

Abstract: A DC/DC converter has an output voltage and sources an output current to a load. The DC/DC converter includes an error amplifier with a reference input and a summing input. The reference input is electrically connected to a reference voltage. The summing input is electrically connected to the output voltage and the output current. The summing input is configured for adding together the output voltage and the output current. The error amplifier issues an error signal and adjusts the error signal dependent at least in part upon the output voltage and the output current. A comparator receives the error signal. The comparator has a ramp input electrically connected to a voltage ramp signal. The comparator issues an output signal that is based at least in part upon said error input. A power switch has an on condition and an off condition, and supplies dc current to the load when in the on condition. The power switch has a control input electrically connected to the comparator output signal.

Abstract: A circuit includes a plurality of DC-to-DC converter circuits and separates in time switching of the respective power switches of the DC-to-DC converter circuits which would otherwise be switching at nearly a same time, such as based upon a same desired output level. The switching time may be separated by inverting a periodic control waveform of at least one of the DC-to-DC converter circuits. The multiple output DC-to-DC converter circuit thereby provides an increased noise margin and operates with greater accuracy and stability. The circuit may also determine when the DC-to-DC converter circuits would otherwise be switching at nearly the same time, and activate the switching time separation responsive thereto. For example, the determination may be made based upon a selectable output level being within a predetermined range of at least one other output level.

Abstract: A DC-to-DC power converter includes at least one power switch, a pulse width modulation circuit for generating control pulses for the at least one power switch, an output inductor connected to the at least one power switch, and a current sensor connected in parallel with the inductor for sensing current passing through the inductor. The current sensor preferably includes a resistor and a capacitor connected together in series. The current sensor is connected to a peak current control loop circuit cooperating with the pulse width modulation circuit for controlling the at least one power switch responsive to the current sensor. The resistor and capacitor preferably have respective values so that the current sensor is a substantially instantaneous current sensor. The output inductor has an inductance and a direct current (DC) resistance defining a first time constant. In one embodiment, the resistor and capacitor of the current sensor define a second time constant within a predetermined range of each other.

Abstract: A DC-to-DC converter includes a pulse width modulation circuit for modulating a switch to produce current pulses having at least a minimum pulse width to thereby control an output voltage to the load. The converter also includes a current limit determining circuit for determining when a desired peak current is no longer sufficient to maintain a desired output voltage thereby defining a current limit condition. In addition, the pulse width modulating circuit, when operating at the minimum pulse width, thereby defines a minimum pulse width condition. Accordingly, the converter preferably further includes an over-current determining circuit for determining an over-current condition responsive to the minimum pulse width condition being reached during a current limit condition. The converter may turn off the switch responsive to an over-current condition. A blanking signal may be used to clamp a comparator and established a minimum pulse width.

Abstract: A monolithic magnetic device having a plurality of transformer elements having single turn primaries and single turn secondaries fabricated on a plate of ferrite which has the outline of a ceramic leadless chip carrier. Each of the magnetic elements has a primary winding formed from a copper via plated on the ferrite. Each element's secondary is another copper via plated over an insulating layer formed over the first layer of copper. The elements' primaries are interconnected on the first copper layer and the elements' secondaries are interconnected on the second copper layer. The configuration and turns ratio of the transformer are determined by the series and or parallel interconnections of the primary and secondaries. Some of the interconnections can be provided by the next higher assembly level through the circuit card, with the same magnetic device providing many turns ratio combinations or values of inductors.

Abstract: Personal leather goods (PLG's) such as wallets, billfolds, pocket calendars have a portion which is required to bend repeatedly. This bending causes cracking and extreme wear which adversely affects the looks of the item and reduces its useful life. Disclosed is a mechanical hinge which attaches to leather-like panels of such PLG's. The hinge includes a set of interleaving knuckles of relatively soft material which form an axial bore along the length of the hinge, the bore receiving a thin pintle made of a relatively stiff but resilient material. The pintle is shorter than the axial length of the bore and is held into the bore by end caps, either separately applied or integrally formed with the hinge leaf. The leaves of the hinge have an overall curving shape having a concave side and convex side to permit the panels to which the hinges attached to remain parallel when materials are received between them.

Abstract: A monolithic magnetic device having a plurality of transformer elements having single turn primaries and single turn secondaries fabricated on a plate of ferrite which has the outline of a ceramic leadless chip carrier. Each of the magnetic elements has a primary winding formed from a copper via plated on the ferrite. Each element's secondary is another copper via plated over an insulating layer formed over the first layer of copper. The elements' primaries are interconnected on the first copper layer and the elements' secondaries are interconnected on the second copper layer. The configuration and turns ratio of the transformer are determined by the series and or parallel interconnections of the primary and secondaries. Some of the interconnections can be provided by the next higher assembly level through the circuit card, with the same magnetic device providing many turns ratio combinations or values of inductors.

Abstract: A boost voltage converter is combined with any DC-DC converter to provide a power system with significant overall power efficiency improvement in applications requiring continuous operation through low line transient levels. The boost converter is normally in a standby mode and only operates when the input DC voltage drops below a predetermined minimum steady state voltage. During steady state operation, a simple, efficient feedthrough of the DC current directly to the DC-DC converter is provided. Efficiency improvements in the combination of boost converter and DC-DC converter result from the reduction of the effective transient range seen by the DC-DC converter, allowing the DC-DC converter components to be designed and selected to significantly reduce their power dissipation during nontransient input steady-state operation.

Abstract: A circulating current control for a phase shifted full bridge inverter is provided to control the powder dissipation and efficiency of the converter responsive to changing operating conditions. The minimum circulating current necessary for zero-voltage switching is regulated by adjusting the reset current of saturable reactors. Therefore, zero-voltage switching can be achieved with a minimum of condition losses. The converters efficiency is optimized over a wide range of operating conditions.

Abstract: A rectifier circuit is provided including a MOSFET having a gate, a drain, and a source terminal. A Schottky diode is connected in series with the MOSFET. The cathode of the Schottky diode is connected to the source of the MOSFET. A zener diode is connected in parallel with a capacitor. A recharging diode has its anode connected to the junction between the MOSFET and the Schottky diode and its cathode connected to the cathode of the zener diode, with the drain serving as the cathode of rectifier circuit and the anode of the Schottky diode serving as the anode of the rectifier circuit. The rectifier circuit has a fast recovery time and is suitable for both high frequency and high voltage, power conversion applications. The rectifier circuit can be used in place of P-N junction fast recovery diodes with less complex snubbers and switch aiding circuits.

Abstract: The present invention is a circuit and method for reducing switching losses in a full bridge, resonant transition, switching power converter. The converter circuit includes a bridge switching circuit having an FET switch in each leg of the bridge. Each FET has a parasitic drain-to-source capacitance. The primary of a power transformer is connected across the bridge. Two secondary windings of the transformer are connected in a center-tapped configuration. A saturable reactor and a rectifier is connected in series with each secondary winding. A control means controls the conduction interval of the FET switches to produce a first and a second half-cycle of converter operation, each half-cycle including an on-time and a free-wheeling interval. The saturable reactors force unequal current distribution in the secondary windings during the free-wheeling intervals such that a primary current is caused to flow.

Abstract: A multi-phase DC/DC converter having an output voltage and including a plurality of converter channels. Each converter channel includes a converter channel input and a converter channel output. Each converter channel is configured for generating a converter channel current and for adjusting said converter channel current in response to a control signal electrically connected to each converter channel input. A control circuit generates an error signal representative of a comparison of the converter output voltage to a reference voltage. The control circuit includes a plurality of control circuit channels, each of which correspond to a converter channel. Each control circuit channel generates a channel current signal representative of a corresponding converter channel current, and generates a differential channel current signal representative of a comparison of the channel current signal to an average current signal.

Abstract: A DC to DC buck pulse width modulator converter circuit includes an input, a high side output and a low side output. A high side switch is electrically connected between a common output node and a voltage supply, and controls a flow of current therethrough dependent upon the high side output. A low side switch is electrically connected between the common output node and ground, and controls a flow of current therethrough dependent upon the low side output. A virtual ground amplifier includes a second input electrically connected to ground. A current feedback resistor is electrically connected intermediate the common output node and a first input of the virtual ground amplifier. A variable impedance component is electrically connected to an output of the virtual ground amplifier and to the first input of the virtual ground amplifier. The impedance of the variable impedance component is varied dependent upon the output of the virtual ground amplifier.