Abstract: In a solar panel array, each solar panel in a series-connected string has a current source connected across its output terminals. The current source generates a programmable output current equal to the difference of the load current drawn from the panel and the current corresponding to the maximum power point (MPP) of the panel. As a result, each of the panels in the string is operated at its MPP. When the array contains multiple strings connected in parallel, a voltage source is additionally connected in series with each string. The voltage sources are programmable to generate corresponding output voltages to enable operation of each panel in each of the multiple strings at its MPP. Respective control blocks providing the current sources and voltage sources automatically determine the MPP of the corresponding panels. In an embodiment, the control blocks are implemented as DC-DC converters in conjunction with measurement and communication units.

Abstract: A system and method for optimizing load current in a string of solar panels. A string of solar panels includes a microprocessor coupled to the string of solar panels. The system includes a first DC-to-DC converter comprising input terminals coupled to a load and output terminals coupled to each solar panel in the string of solar panels. The first DC-to-DC converter is operable to supply a compensatory power for compensating a drop in the peak current arising due to shading of one or more solar panels. Moreover, the system includes a second DC-to-DC converter coupled to the first DC-to-DC converter. The second DC-to-DC converter is operable as one of a voltage adder and a voltage subtractor to generate a compensatory voltage for compensating a drop in the load current arising due to panel mismatch among the string of solar panels.

Abstract: A spread-spectrum switching regulator for eliminating modulation ripple includes high gain amplifier that is responsive to reference voltage and feedback voltage of feedback loop to generate differential voltage, the feedback voltage being one of output voltage of the spread-spectrum switching regulator and a fraction of the output voltage; compensation circuit, coupled to the high gain amplifier, that maintains stability of the feedback loop to generate error level voltage in response to differential voltage; ramp generator that generates ramp waveform with slope adaptable to switching frequency to maintain duty cycle at constant value; pulse width modulator, coupled to compensation circuit and ramp generator, that compares error level voltage and ramp waveform to generate pulsed waveform; driver circuit, coupled to pulse width modulator, that drives the pulsed waveform to alternately switch a pair of transistors; and LC network, coupled to the pair of transistors, to average pulsed waveform to the output vo

Abstract: A system for generating electric power includes a first DC source, a second DC source and a shared optimizer. The first DC source provides a first voltage across a first node and a second node, while the second DC source provides a second voltage across the second node and a third node. The shared optimizer is designed to provide a first programmable current source between the first node and the second node as well as a second programmable current source between the second node and the third node. In an embodiment, the first and second DC sources are solar panels, and the optimizer includes a DC-DC converter, which operates to maximize power output of the solar panels. The use of a single (shared) optimizer may obviate the need for separate optimizers for each solar panel, and thereby reduce system cost.

Abstract: A spread-spectrum switching regulator for eliminating modulation ripple includes high gain amplifier that is responsive to reference voltage and feedback voltage of feedback loop to generate differential voltage, the feedback voltage being one of output voltage of the spread-spectrum switching regulator and a fraction of the output voltage; compensation circuit, coupled to the high gain amplifier, that maintains stability of the feedback loop to generate error level voltage in response to differential voltage; ramp generator that generates ramp waveform with slope adaptable to switching frequency to maintain duty cycle at constant value; pulse width modulator, coupled to compensation circuit and ramp generator, that compares error level voltage and ramp waveform to generate pulsed waveform; driver circuit, coupled to pulse width modulator, that drives the pulsed waveform to alternately switch a pair of transistors; and LC network, coupled to the pair of transistors, to average pulsed waveform to the output vo

Abstract: A circuit for sensing load current of a voltage regulator. The circuit includes a power transistor and a mirror transistor. A first transistor sizing circuit is coupled to the power transistor and is operable to control size of the power transistor based on a bias voltage of the power transistor, thereby regulating a first voltage for varying load conditions. The circuit also includes a feedback amplifier coupled to the power transistor and the mirror transistor. A transistor is coupled to the feedback amplifier and the mirror transistor. An analog to digital converter (ADC) is coupled to the transistor. A second transistor sizing circuit is coupled to the mirror transistor, the transistor, and the ADC. The second transistor sizing circuit is responsive to an output voltage to control size of the mirror transistor, thereby ensuring that accuracy of output voltage sensed by ADC is not limited by ADC's resolution.

Abstract: In a solar panel array that includes a string of series-connected panels, the load current flowing through the string is measured. The peak current (Ipp) of a panel in the string is determined. A current equal to the difference of the load current and the peak current (Ipp) is generated in a current source connected across the output terminals of the panel. The panel is thereby operated at its maximum power point (MPP). To determine the peak current (Ipp) of the panel, the magnitude of current flowing through the panel is iteratively changed and the corresponding power generated by the panel is computed. The change in the current through the panel and the measurement of the corresponding power are repeated until a maximum power is determined as being generated by the panel. The maximum power corresponds to the maximum power point (MPP) and the peak current (Ipp) of the panel.

Abstract: A transient recovery circuit for switching devices. The transient recovery circuit includes a detecting circuit for detecting a rapid transient in an output voltage of a switching device by detecting a rate of the output voltage transient; an auxiliary controlling circuit in a feedback loop of the switching device for correcting the output voltage by changing a bandwidth of the feedback loop if the rapid transient is detected; and an initializing circuit for initializing the feedback loop to expected operating points in a continuous conduction mode after correcting the output voltage.

Abstract: A transient recovery circuit for switching devices. The transient recovery circuit includes a detecting circuit for detecting a rapid transient in an output voltage of a switching device by detecting a rate of the output voltage transient; an auxiliary controlling circuit in a feedback loop of the switching device for correcting the output voltage by changing a bandwidth of the feedback loop if the rapid transient is detected; and an initializing circuit for initializing the feedback loop to expected operating points in a continuous conduction mode after correcting the output voltage.

Abstract: A transient recovery circuit for switching devices. The transient recovery circuit includes a detecting circuit for detecting a rapid transient in an output voltage of a switching device by detecting a rate of the output voltage transient; an auxiliary controlling circuit in a feedback loop of the switching device for correcting the output voltage by changing a bandwidth of the feedback loop if the rapid transient is detected; and an initializing circuit for initializing the feedback loop to expected operating points in a continuous conduction mode after correcting the output voltage.

Abstract: Efficient switch cascode architecture for switching devices, such as switching regulators. The cascode architecture includes a switching stage responsive to an external driver signal for switching transitions, and a bias generator operative to bias the cascode transistor of the switching stage to protect the switching stage from damage during the switching transitions.

Abstract: In a solar panel array, each solar panel in a series-connected string has a current source connected across its output terminals. The current source generates a programmable output current equal to the difference of the load current drawn from the panel and the current corresponding to the maximum power point (MPP) of the panel. As a result, each of the panels in the string is operated at its MPP. When the array contains multiple strings connected in parallel, a voltage source is additionally connected in series with each string. The voltage sources are programmable to generate corresponding output voltages to enable operation of each panel in each of the multiple strings at its MPP. Respective control blocks providing the current sources and voltage sources automatically determine the MPP of the corresponding panels. In an embodiment, the control blocks are implemented as DC-DC converters in conjunction with measurement and communication units.

Abstract: In a solar panel array that includes a string of series-connected panels, the load current flowing through the string is measured. The peak current (Ipp) of a panel in the string is determined. A current equal to the difference of the load current and the peak current (Ipp) is generated in a current source connected across the output terminals of the panel. The panel is thereby operated at its maximum power point (MPP). To determine the peak current (Ipp) of the panel, the magnitude of current flowing through the panel is iteratively changed and the corresponding power generated by the panel is computed. The change in the current through the panel and the measurement of the corresponding power are repeated until a maximum power is determined as being generated by the panel. The maximum power corresponds to the maximum power point (MPP) and the peak current (Ipp) of the panel.

Abstract: A circuit for sensing load current of a voltage regulator. The circuit includes a power transistor and a minor transistor. A first transistor sizing circuit is coupled to the power transistor and is operable to control size of the power transistor based on a bias voltage of the power transistor, thereby regulating a first voltage for varying load conditions. The circuit also includes a feedback amplifier coupled to the power transistor and the mirror transistor. A transistor is coupled to the feedback amplifier and the mirror transistor. An analog to digital converter (ADC) is coupled to the transistor. A second transistor sizing circuit is coupled to the mirror transistor, the transistor, and the ADC. The second transistor sizing circuit is responsive to an output voltage to control size of the minor transistor, thereby ensuring that accuracy of output voltage sensed by ADC is not limited by ADC's resolution.

Abstract: Efficient switch cascode architecture for switching devices, such as switching regulators. The cascode architecture includes a switching stage responsive to an external driver signal for switching transitions, and a bias generator operative to bias the cascode transistor of the switching stage to protect the switching stage from damage during the switching transitions.

Abstract: A transient recovery circuit for switching devices. The transient recovery circuit includes a detecting circuit for detecting a rapid transient in an output voltage of a switching device by detecting a rate of the output voltage transient; an auxiliary controlling circuit in a feedback loop of the switching device for correcting the output voltage by changing a bandwidth of the feedback loop if the rapid transient is detected; and an initializing circuit for initializing the feedback loop to expected operating points in a continuous conduction mode after correcting the output voltage.