Abstract: A calibration circuit for synchronizing a switching regulator includes a phase locked loop circuit to generate one or more control signals based on an output of the switching regulator. A digital calibration circuit provides a digital output signal based on the control signals from the phase locked loop circuit. A timer can provide switching pulses to the switching regulator based on the digital output signal and the control signals. The phase locked loop circuit can adjust the control signals based on a reference clock signal to synchronize a feedback signal of the switching regulator with the reference clock signal.

Abstract: A method and system of providing an active differential resistor. The active differential resistor includes a diode having a first node and a second node. There is a capacitor coupled in series between the first node of the diode and an input of the active differential resistor. There is a current source coupled across the first node and the second node of the diode and configured to forward bias the diode such that a Johnson-Nyquist noise of the active differential resistor is replaced by a shot noise.

Abstract: Techniques are provided for low, or deep, dimming of a light-emitting diode (LED) load. In an example, a low dimming circuit can include a target current detector configured to provide an output indicative of a target current of a power stage of a pulse width modulated driver, and a control circuit configured to receive a PWM signal of the PWM LED driver, to control a first transition to a first state of a power switch of the power stage during an on-interval of a first PWM cycle of the PWM signal, and to control a second transition to the first state of the power switch using the output of the target current detector during an off interval of the first PWM cycle.

Abstract: A switched resonant power converter includes multiple switching transistors, a resonant circuit comprising a capacitor and an inductor, and an auxiliary soft-start bypass circuit that bypasses a default switching path that includes a first switching transistor of the switching transistors, and provides an alternative path through an impedance element. A corresponding control circuit is configured to switch between an operational mode in which the default switching path is periodically activated while the alternative path is deactivated to provide a first frequency-responsive power through the resonant circuit, and a soft-start mode in which the alternative path is periodically activated while the default switching path is deactivated to provide a second frequency-responsive power through the resonant circuit.

Abstract: An energy storage stack balancing circuit may balance a set of serially connected energy storage devices. An electronic switching system may control the delivery of energy into and out of the inductor. A controller may control the electronic switching system so as to cause energy to be transferred: from one of the energy storage devices into the inductor and then out of the inductor and into a different one, a subset, or all of the energy storage devices; or from a subset of the energy storage devices into the inductor and then out of the inductor and into one, a different subset, or all of the energy storage devices; or from all of the energy storage devices into the inductor and then out of the inductor and into one or a subset the energy storage devices.

Abstract: An output capacitor of a switching converter filters the triangular current waveform output by an inductor. An auxiliary capacitor, having a capacitance that is much smaller than a capacitance of the output capacitor, is coupled in parallel with the output capacitor so as to conduct a portion of the inductor current. A slope detector circuit determines a slope of the auxiliary capacitor current, and outputs a slope signal corresponding to the slope. A process circuit receives the slope signal and a signal corresponding to the inductor current. Since the auxiliary capacitor current slope is known, along with the auxiliary capacitance value and inductor current, the process circuit can derive the value of the output capacitor by applying a scaling factor. The derived value can be used to dynamically tweak the compensation of the feedback loop or identify a failure of the output capacitor.

Abstract: A network device includes a network interface circuit, a microprocessor, a timing circuit, and a microsequencer. The timing circuit is configured to, based on a primary timing signal, generate a time signature and switch the network device from an inactive state to an active state when the time signature satisfies a predetermined threshold length of time for packet transmission. The microsequencer circuit is configured to, in response to the network device being switched to the active state, activate and configure the network interface circuit for the packet transmission, independent of the microprocessor and delays encountered by the microprocessor. The device also reduces energy consumption by using a lower frequency secondary oscillator to maintain timing information when a higher frequency primary oscillator is inactivated.

Abstract: A power supply system includes a power source; a load device configured to receive power from the power source; and a power interface device coupled to the power source and the load device and configured to change a first voltage provided by the power source to a second voltage for operating the load device. The power interface device include a main switching converter configured to operate at a first switching frequency and source low frequency current to the load device and an auxiliary switching converter coupled in parallel with the main switching converter and configured to operate at a second and different switching frequency and source fast transient high frequency current to the load device.

Abstract: A controller may control a buck-boost regulator having an input voltage and an output voltage. The controller may include: circuitry that causes the output voltage of the buck-boost regulator to be at the bottom of a pre-determined voltage window when the input voltage goes below the bottom of the pre-determined voltage window: circuitry that causes the output voltage of the buck-boost regulator to be at the top of the pre-determined voltage window when the input voltage goes above the top of the pre-determined voltage window; and circuitry that causes the buck-boost regulator to pass the input voltage through the buck-boost regulator so as to cause the voltage output of the buck-boost regulator to be at the same level as the input voltage when the input voltage is within the pre-determined voltage window.

Abstract: Techniques are provided for low, or deep, dimming of a light-emitting diode (LED) load. In an example, a method of adjusting an initial voltage of a driver circuit for an LED load can include providing current to an LED load from a power stage of the driver during an on-time of a pulse-width modulation (PWM) cycle, receiving error current information of the driver circuit at a low-dimming control circuit of the driver, and adjusting a voltage of an output capacitor coupled to the driver during an off-time of the PWM cycle, the charge adjustment based on the error current information.

Abstract: Techniques are provided for low, or deep, dimming of a light-emitting diode (LED) load. In an example, a method for deep dimming a light-emitting diode (LED) load can include, when a current of an inductor does not reach a target current by the end of an on-time of a pulse-width modulation (PWM) switch cycle, and, during an initial on-time of the PWM switch cycle, allowing the current of the inductor to reach the target current during a next “off” time interval of the PWM switch cycle, wherein the inductor is coupled to the LED via a PWM switch, and in response to the current of the inductor reaching the target current before the end of the on-time of a subsequent PWM switch cycle, interrupting energizing of the inductor at the end of the on-time of the PWM switch cycle.

Abstract: A PoDL system includes a PSE connected via a wire pair to a PD, where differential data and DC power are transmitted over the same wire pair. Typically, low voltage/current detection and classification routines are required upon every powering up of the system to allow the PD to convey its PoDL requirements to the PSE. Various techniques are described that simplify or obviate such start-up routines or enable increased flexibility for the PoDL system. Such techniques include: ways to specify a particular PD operating voltage; ways to disable the PD's UVLO circuit during such routines; using opposite polarity voltages for the two routines; using voltage limiters or surge protectors to convey the PoDL information; detecting loop resistance; using a PSE memory to store previous results of the routines; and powering the PD communication circuit using the wire pair while the PD load is powered by an alternate power source.

Abstract: In one embodiment, a PoDL system includes a PSE that uses high side and low side circuit breakers that uncouple the PSE voltage source from the wire pair in the event that a fault is detected. Faults may include a temporary short to ground, or to a battery voltage, or between the wires. The breakers perform an automatic retry operation in the event the fault has been removed. The voltages on the wires in the wire pair may be monitored to determine whether the voltages are within a normal range or indicative of a fault condition. Other embodiments are disclosed.

Abstract: An inductor current-sensing circuit for measuring a current in an inductor includes (a) a first RC network coupled between a first terminal of the inductor and a reference voltage source; and (b) a second RC network coupled between a second terminal of the inductor and the reference voltage source. The first RC network and the second RC network each have a time constant substantially equal to the ratio between the inductance and the DC resistance of the inductor. The inductor which current is being measured may be a primary inductor of a four-switch buck boost converter receiving an input voltage and providing an output voltage.

Abstract: A power interface device includes a main switching converter, an auxiliary switching converter, a feedback sense circuit, an error amplifier, a high pass filter, a transient detection circuit, and an auxiliary control circuit. The transient detection circuit is configured to receive the higher frequency component of the transient signal and output an enable signal when the higher frequency component of the transient signal falls outside of an operating window range defined by a first threshold and a second threshold and output a disable signal when the higher frequency component of the transient signal stays within the operating window range. The auxiliary control circuit configured to activate the auxiliary switching converter in accordance with the enable signal and to deactivate the auxiliary switching converter in accordance with the disable signal.

Abstract: A wireless mesh network is provided with equipment and methods for monitoring and enforcement of license terms. The network includes a plurality of wireless network nodes, a wireless access point, and a network manager in communication with the access point and with the network nodes via the access point. At least one of the network nodes and the access point includes license information embedded in the device hardware, and the network manager provides services to the wireless network subject to license terms determined based on the license information embedded within the network node or access point. Additionally, the network manager is in communication with a user application external to the network, and relays communication between the user application and the wireless network. The network manager modulates communications relayed between the user application and the wireless network subject to the license information embedded within the network node or access point.

Abstract: A power interface device includes a main switching converter and an auxiliary switching converter. The main switching converter is coupled to an input terminal and an output terminal and configured to operate at a first switching frequency to source a low frequency current from the input terminal to the output terminal. The auxiliary switching converter is coupled to the input terminal and the output terminal in parallel with the main switching converter and configured to operate at a second and higher switching frequency than the first switching frequency to source a fast transient high frequency current from the input terminal to the output terminal.

Abstract: A method and a circuit take a measurement of a sensor having first, second and third lead wires by: (a) providing first, second and third terminals for voltage measurements; (b) connecting a current sensing device (e.g., a reference resistor) to provide a signal at the third terminal that is indicative of the current in the third lead wire of the sensor; (c) connecting a first protective device between the first lead wire of the sensor and the first terminal; (d) connecting a second protective device between the second lead wire of the sensor and the second terminal; (e) connecting a first current source to the first lead wire of the sensor; (f) connecting a second current source to the second lead wire of the sensor; and (g) measuring a first voltage across the first and second terminals and a second voltage across the third terminal and the voltage reference.

Abstract: A switched capacitor power converter includes multiple switching transistors in a default switching path, and an auxiliary soft-charge bypass circuit which includes one or more auxiliary transistors and an impedance element, and provides an auxiliary circuit path through the auxiliary transistor(s) to charge a plurality of capacitors within the converter circuit when the auxiliary soft-charge bypass circuit is activated and at least one of the switching transistors is deactivated. A corresponding control circuit switches the converter circuit from a soft-charging mode in which the auxiliary soft-charge bypass circuit is activated and a switching transistor is deactivated, to an operational mode in which the auxiliary soft-charge bypass circuit is deactivated, the control circuit periodically switching the one or more auxiliary transistors during the soft-charging mode in place of the deactivated switching transistor(s).

Abstract: A switching regulator circuit incorporates an offset circuit, connected in a control loop of the regulator circuit, that, in response to a signal indicating an imminent load current step, adjusts a duty cycle of a power switch for the current step prior to the regulator circuit responding to a change in output voltage due to the current step. In one embodiment, a load controller issues a digital signal shortly before a load current step. The digital signal is decoded and converted to an analog offset signal in a feedback control loop of the regulator to immediately adjust a duty cycle of the switch irrespective of the output voltage level. By proper timing of the offset, output voltage ripple is greatly reduced. The current offset may also be used to rapidly change the output voltage in response to an external signal requesting a voltage step.