Abstract: A switching power converter is provided that includes a detector to detect whether a controller power supply voltage has fallen below a threshold voltage during a dormant period in which a power switch is no longer cycling to deliver power to a load. In response to a detection of such a threshold crossing by the detector, a controller powered by the controller power supply voltage is configured to cycle the power switch to replenish the controller power supply voltage.

Abstract: A line ripple compensation technique is provided for a switching power converter operating in both a pulse frequency mode of operation and a pulse width modulation mode of operation.

Abstract: A switching power converter is provided that cycles a power switch during a group pulse mode of operation to produce a train of pulses within a group period responsive to a control voltage being within a group mode control voltage range. Depending upon the control voltage, the number of pulses in each train of pulses is varied to provide a linear power delivery to the load.

Abstract: A variable-level flyback power converter is configured to provide an accurate output voltage at various regulation levels. The variable-level flyback power converter may include a switch coupled to a secondary winding of a transformer, a diode coupled to a primary winding of the transformer, and a controller coupled to the switch. The controller may scale an initial reference voltage based on a desired output voltage and a forward voltage drop across the diode, compare the scaled reference voltage with a feedback voltage sensed at an auxiliary winding of the transformer to generate an error signal, and modulate a pulse signal provided to the switch based on the error voltage.

Abstract: A method for estimating an output voltage of a power converter comprises sensing a voltage waveform representative of the output voltage; and detecting a first gap and a second gap. The first gap is between a time when the sensed voltage waveform crosses a first voltage reference and a time when the sensed voltage waveform crosses a second voltage reference at a voltage offset below the first voltage reference. The second gap is between a time when the sensed voltage waveform crosses a third voltage reference and a time when the sensed voltage waveform crosses the second voltage reference, the third voltage referenced at a predetermined voltage above the second voltage reference. Responsive to the first gap exceeding a threshold, a tracking error is computed based on the first gap; and responsive to the first gap not exceeding the threshold, the tracking error is computed based on the second gap.

Abstract: A switching power converter controller is provided that transitions between constant voltage pulse frequency modulation operation and constant current operation responsive to a comparison of a peak voltage for the constant voltage pulse frequency modulation operation and a peak voltage for the constant current operation.

Abstract: A flyback converter is provided with a controller that is configured to analyze the reflected feedback voltage waveforms to determine the presence of a ground connection fault for the auxiliary winding.

Abstract: A variable-level flyback power converter is configured to provide an accurate output voltage at various regulation levels. The variable-level flyback power converter may include a switch coupled to a secondary winding of a transformer, a diode coupled to a primary winding of the transformer, and a controller coupled to the switch. The controller may scale an initial reference voltage based on a desired output voltage and a forward voltage drop across the diode, compare the scaled reference voltage with a feedback voltage sensed at an auxiliary winding of the transformer to generate an error signal, and modulate a pulse signal provided to the switch based on the error voltage.

Abstract: A novel and useful apparatus for and method of software based phase locked loop (PLL). The software based PLL incorporates a reconfigurable calculation unit (RCU) that is optimized and programmed to sequentially perform all the atomic operations of a PLL or any other desired task in a time sharing manner. An application specific instruction-set processor (ASIP) incorporating the RCU includes an instruction set whose instructions are optimized to perform the atomic operations of a PLL. The RCU is clocked at a fast enough processor clock rate to insure that all PLL atomic operations are performed within a single PLL reference clock cycle.

Abstract: A novel and useful apparatus for and method of software based phase locked loop (PLL). The software based PLL incorporates a reconfigurable calculation unit (RCU) that is optimized and programmed to sequentially perform all the atomic operations of a PLL or any other desired task in a time sharing manner. An application specific instruction-set processor (ASIP) incorporating the RCU includes an instruction set whose instructions are optimized to perform the atomic operations of a PLL. The RCU is clocked at a fast enough processor clock rate to insure that all PLL atomic operations are performed within a single PLL reference clock cycle.

Abstract: A direct charging method is provided that alerts a mobile device when a switching power converter is operating in a constant-current mode to alert the mobile device of an output current without the use of a secondary-side current sense resistor.

Abstract: A switching power converter is provided that communicates with a mobile device to receive a value of a load detection current. The switching power converter adjusts the cycling of a power switch until a constant current mode of operation is entered with a known output current driving the mobile device. The switching power converter subtracts the load current from the output current to measure a soft-short circuit current.

Abstract: A flyback converter is provided with a controller that is configured to analyze the reflected feedback voltage waveforms to determine the presence of a ground connection fault for the auxiliary winding.

Abstract: An apparatus comprises an output port to be connected to a load; a first input port to receive a first input signal; and a second input port coupled between the first input port and the output port, to receive a second input signal. The apparatus further comprises a coupling circuit to couple the second input signal to the output port and a frequency isolation circuit that has a frequency response to propagate the first input signal to the output port but prevent the second input signal from propagating to the first input port. The apparatus also comprises a detection circuit to determine a voltage of an output signal at the output port, the output signal having a first amplitude range with a load absent at the output port and having a second amplitude range lower than the first amplitude range with the load present at the output port.

Abstract: A device for determining impedance at a data pin of a communication interface. In one embodiment, the device includes a current source configured to selectively inject a test current to the data pin. The device also includes a sensing circuit for sensing a first test voltage corresponding to a voltage at the data pin without the test current injected, and a second test voltage corresponding to another voltage at the data pin with the test current injected. The sensing circuit determines the impedance at the data pin based on the first test voltage and the second test voltage.

Abstract: A switching power converter is provided that cycles a power switch during a group pulse mode of operation to produce a train of pulses within a group period responsive to a control voltage being within a group mode control voltage range.

Abstract: History-based valley mode switching techniques and systems are provided to reduce the frequency spreading of switching noise in a switching power converter.

Abstract: Embodiments described herein describe a power supply configured to provide power to an output load via a power supply transformer. The power supply includes a controller configured to operate in a configuration state and an operating state. During the configuration state, the controller receives a configuration signal from a sense circuit coupled to the controller and selects one of a plurality of operating modes from the configuration signal. During the operating state, the controller controls a switch coupled to the transformer based on the selected operating mode and a sense signal received from the sense circuit representative of the power provided to the output load by the power supply. When the switch is closed, current flows from a power source through the transformer, and when the switch is open, current is prevented from flowing from the power source through the transformer.

Abstract: A novel and useful apparatus for and method of software based phase locked loop (PLL). The software based PLL incorporates a reconfigurable calculation unit (RCU) that is optimized and programmed to sequentially perform all the atomic operations of a PLL or any other desired task in a time sharing manner. An application specific instruction-set processor (ASIP) incorporating the RCU includes an instruction set whose instructions are optimized to perform the atomic operations of a PLL. The RCU is clocked at a fast enough processor clock rate to insure that all PLL atomic operations are performed within a single PLL reference clock cycle.

Abstract: A power converter includes a transformer with a primary and a secondary winding and a switch. A controller of the power converter at the primary winding side of the transformer generates a control signal to turn on or turn off the switch, the switch being turned on responsive to the control signal being in a first state and the switch being turned off responsive to the control signal being in a second state. The controller determines current through the primary winding generated while the switch is turned on and indirectly detects an input voltage to the power converter based on the current through the primary winding generated while the switch is turned on. The controller in turn may detect conditions such as a loss of power or brown out at the input of the power converter based on the indirectly detected input voltage.