Abstract: A phase-modulated, double-ended, full-bridge topology-based DC-AC converter supplies AC power to a load, such as a cold cathode fluorescent lamp used to back-light a liquid crystal display. First and second converter stages generate respective first and second sinusoidal voltages having the same frequency and amplitude, but having a controlled phase difference therebetween. By employing a voltage controlled delay circuit to control the phase difference between the first and second sinusoidal voltages, the converter is able to vary the amplitude of the composite voltage differential produced across the opposite ends of the load.

Abstract: A phase-modulated, double-ended, half-bridge topology-based DC-AC converter supplies AC power to a load, such as a cold cathode fluorescent lamp used to back-light a liquid crystal display. First and second converter stages generate respective first and second sinusoidal voltages having the same frequency and amplitude, but having a controlled phase difference therebetween. By employing a voltage controlled delay circuit to control the phase difference between the first and second sinusoidal voltages, the converter is able to vary the amplitude of the composite voltage differential produced across the opposite ends of the load.

Abstract: A modulator control circuit including a linear control circuit, a non-linear control circuit, and a combiner. The linear control circuit has an input receiving a compensation signal indicative of an output parameter and an output providing a first control signal. The non-linear control circuit has an input receiving the compensation signal and an output providing a second control signal. The non-linear control circuit senses transients of the compensation signal not otherwise detected by the linear control circuit and asserts the second control signal indicative thereof. The combiner combines the first and second control signals to provide a pulse width modulation signal for controlling the output parameter, such as output voltage or the like.

Abstract: A voltage converter includes a plurality of voltage converter circuits, each voltage converter circuit having a topology, and a control circuit coupled to the voltage converter circuits. The control circuit is operable to select one of the voltage converter circuits to provide an output power on an output node. The control circuit selects one of the voltage converter circuits in response to a parameter associated with the operation of the voltage converter, such as a parameter associated with the output power on the output node.

Abstract: Methods and apparatus of dynamic topology power converters are provided. One method includes monitoring at least one variable of the power converter and based on the at least one monitored variable, using a converter topology selected between at least a full-bridge converter topology and a half-bridge converter topology to achieve an efficient operation at a then current operational load.

Abstract: An embodiment of a hysteretic power-supply controller includes a signal generator, frequency adjuster, and signal combiner. The signal generator is operable to generate a switching signal having a first level in response to a control signal being greater than a first reference value and having a second level in response to the control signal being less than a second reference value, the switching signal having an actual frequency and being operable to drive a switching stage that generates a regulated output signal. The frequency adjuster is operable to generate a frequency-adjust signal that is related to a difference between the actual frequency and a desired frequency. And the signal combiner is operable to generate the control signal from the frequency-adjust signal and the regulated output signal. Such a hysteretic power-supply controller may allow one to set the switching frequency to a desired value independently of the parameters of the power supply.

Abstract: A double-ended, DC-AC converter supplies AC power to a load, such as a cold cathode fluorescent lamp used to back-light a liquid crystal display. First and second converter stages generate respective first and second sinusoidal voltages having the same frequency and amplitude, but having a controlled phase difference therebetween. By employing a voltage controlled delay circuit to control the phase difference between the first and second sinusoidal voltages, the converter is able to vary the amplitude of the composite voltage differential produced across the opposite ends of the load. The converter may be either voltage fed or current fed.

Abstract: A current-sharing multiphase sliding-mode switching power supply (24) and method of operation are presented. A bipolar power source (22) is coupled to a switch (30) for each phase (28), each switch (30) is in turn coupled to an inductance (32), and a capacitance (36) is coupled to the inductances (32) and across a load (26). A sliding-surface generator (78) generates a sliding surface (?). A current-balance control (80) computes a reference current as a summary statistic (IX) of inductive currents (IL) through the inductances (32), calculates an error current (IE) for each phase (28) as a difference between the summary statistic (IX) and the inductive current (IL), and adjusts the sliding surface (?) for each phase (28) so that all inductive currents (IL) are substantially equal to the summary statistic (IX). A switching circuit (138) switches the switches (30) in response to the sliding surface (?).

Abstract: A multiphase sliding-mode switching power supply (24) and a method of operating the power supply (24) are provided. A switch (30) for each phase (28) is coupled to a bipolar power source (22), with each switch (30) effecting one phase (28). An inductance (32) is coupled to each switch (30), and a capacitance (36) is coupled to the inductances (32). A load (26) is coupled across the capacitance (36). A sliding-surface generator (78) is coupled to the monitor circuit (38) and generates a single sliding surface (?) for all phases (28). A translation circuit (102) is coupled to the sliding-surface generator (78) and configured to translate the sliding surface (?) into a stream of switching pulses (86). A transient control (52) is coupled to the translation circuit (102) and configured to adjust said stream of switching pulses upon detection of an out-of-range transient.

Abstract: A sliding-mode switching power supply (24) having N phases (28) and a method of operating the power supply (24) are provided. N switches (30) are coupled to a bipolar power source (22), with each switch (30) effecting one phase (28). An inductance (32) is coupled to each switch (30), and a capacitance (36) is coupled to the inductances (32). A load (26) is coupled across the capacitance (36). A monitor circuit (38) is coupled to the inductances (32) and the capacitance (36) and configured to monitor an output voltage (VOut) of the power supply (24). A first state-variable generator (42) generates a first state variable (first state variable x1) in response to the output voltage (VOut), and a second sate variable generator (44) synthesizes a second state variable (second state variable x2) from the first state variable (x1).

Abstract: A sliding-mode switching power supply (24) having N phases (28) and a method of operating the power supply (24) are provided. N switches (30) are coupled to a bipolar power source (22), with each switch (30) effecting one phase (28). An inductance (32) is coupled to each switch (30), and a capacitance (36) is coupled to the inductances (32). A load (26) is coupled across the capacitance (36). A monitor circuit (38) is coupled to the inductances (32) and the capacitance (36) and configured to monitor currents (IL) through the inductances (32) and/or a voltage (VC) across the capacitance (36). A sliding-surface generator (78) is coupled to the monitor circuit (38) and generates a single sliding surface (?) for all phases (28). A constant-frequency control (104) forms a variable window (??) for the sliding surface (?). A switching circuit (138) switches the switches (30) at a switching frequency (fS) determined by the variable window (??).

Abstract: A multiphase DC-to-DC converter includes at least two phase circuits each having upper and lower power switches and a front-end inductor that is operative for forming a resonant tank circuit with the phase circuits to ensure zero voltage switching and minimizing power losses.

Abstract: A sliding-mode switching power supply (24) having N phases (28) and a method of operating the power supply (24) are provided. N switches (30) are coupled to a bipolar power source (22), with each switch (30) effecting one phase (28). An inductance (32) is coupled to each switch (30), and a capacitance (36) is coupled to the inductances (32). A load (26) is coupled across the capacitance (36). A monitor circuit (38) is coupled to the inductances (32) and the capacitance (36) and configured to monitor currents (IL) through the inductances (32) and/or a voltage (VC) across the capacitance (36). A sliding-surface generator (78) is coupled to the monitor circuit (38) and generates a single sliding surface (?) for all phases (28). A constant-frequency control (104) forms a variable window (??) for the sliding surface (?). A switching circuit (138) switches the switches (30) at a switching frequency (fS) determined by the variable window (??).

Abstract: A sliding-mode switching power supply (24) having N phases (28) and a method of operating the power supply (24) are provided. N switches (30) are coupled to a bipolar power source (22), with each switch (30) effecting one phase (28). An inductance (32) is coupled to each switch (30), and a capacitance (36) is coupled to the inductances (32). A load (26) is coupled across the capacitance (36). A monitor circuit (38) is coupled to the inductances (32) and the capacitance (36) and configured to monitor currents (IL) through the inductances (32) and/or a voltage (VC) across the capacitance (36). A sliding-surface generator (78) is coupled to the monitor circuit (38) and generates a single sliding surface (?) for all phases (28). A constant-frequency control (104) forms a variable window (??) for the sliding surface (?). A switching circuit (138) switches the switches (30) at a switching frequency (fS) determined by the variable window (??).

Abstract: A phase-modulated, double-ended, half-bridge topology-based DC-AC converter supplies AC power to a load, such as a cold cathode fluorescent lamp used to back-light a liquid crystal display. First and second converter stages generate respective first and second sinusoidal voltages having the same frequency and amplitude, but having a controlled phase difference therebetween. By employing a voltage controlled delay circuit to control the phase difference between the first and second sinusoidal voltages, the converter is able to vary the amplitude of the composite voltage differential produced across the opposite ends of the load.

Abstract: A phase-modulated, double-ended, full-bridge topology-based DC-AC converter supplies AC power to a load, such as a cold cathode fluorescent lamp used to back-light a liquid crystal display. First and second converter stages generate respective first and second sinusoidal voltages having the same frequency and amplitude, but having a controlled phase difference therebetween. By employing a voltage controlled delay circuit to control the phase difference between the first and second sinusoidal voltages, the converter is able to vary the amplitude of the composite voltage differential produced across the opposite ends of the load.

Abstract: A multi-stage, push-pull driven, resonant DC-AC converter ties the center-taps of primary windings of respective push-pull stages together, and drives each center-tap with a current source. Tying the center-taps of the primary windings of the respective DC-AC converters' transformers together forces the voltages at these locations to be the same, so as to achieve mutual resonant synchronization between the two stages. Connecting the center-taps to a current source provides the necessary power for each stage and allows for a variation in current between stages, as the center-tap voltages track one another. The tied-together center-tap voltage is monitored to obtain the zero voltage switching required for efficient operation of switching devices of each DC-AC converter stage.

Abstract: A multi-stage, push-pull driven, resonant DC-AC converter ties the center-taps of primary windings of respective push-pull stages together, and drives each center-tap with a current source. Tying the center-taps of the primary windings of the respective DC-AC converters' transformers together forces the voltages at these locations to be the same, so as to achieve mutual resonant synchronization between the two stages. Connecting the center-taps to a current source provides the necessary power for each stage and allows for a variation in current between stages, as the center-tap voltages track one another. The tied-together center-tap voltage is monitored to obtain the zero voltage switching required for efficient operation of switching devices of each DC-AC converter stage.

Abstract: A linear predictive system for a DC—DC converter including a linear predictive controller, first and second adders and a multiplier. The DC—DC converter generates an output signal and includes a digital compensation block that converts a feedback error signal into a main duty cycle signal. The linear predictive controller predicts linear changes of the main duty cycle signal in response to changes of the output signal and provides a predictive duty cycle signal. The first adder subtracts the predictive duty cycle signal from the main duty cycle signal to provide a duty cycle delta. The multiplier multiplies the duty cycle delta by a gain factor to provide a duty cycle delta sample. The second adder adds the duty cycle delta sample to the first duty cycle signal to generate an adjusted duty cycle signal.

Abstract: A double-ended, DC-AC converter supplies AC power to a load, such as a cold cathode fluorescent lamp used to back-light a liquid crystal display. First and second converter stages generate respective first and second sinusoidal voltages having the same frequency and amplitude, but having a controlled phase difference therebetween. By employing a voltage controlled delay circuit to control the phase difference between the first and second sinusoidal voltages, the converter is able to vary the amplitude of the composite voltage differential produced across the opposite ends of the load. The converter may be either voltage fed or current fed.