If the capacitance of a snubber capacitor, the inductance of a coil and the magnitude of a resistor are specified such that the resonance frequency of the snubber circuit coincides with the ringing frequency of the transistor, and the impedance of the first loop at the resonance frequency becomes smaller than the impedance of the second loop at the resonance frequency, a current component due to ringing flows in the snubber circuit, and energy is consumed by the resistor. Therefore, it is possible to quickly converge ringing.

If the capacitance of a snubber capacitor, the inductance of a coil and the magnitude of a resistor are specified such that the resonance frequency of the snubber circuit coincides with the ringing frequency of the transistor, and the impedance of the first loop at the resonance frequency becomes smaller than the impedance of the second loop at the resonance frequency, a current component due to ringing flows in the snubber circuit, and energy is consumed by the resistor. Therefore, it is possible to quickly converge ringing.

An object of this disclosure is to implement a Buck, Boost, or other switching converter, with a circuit to supply a reference voltage and Adaptive Voltage Positioning (AVP), by means of a servo and programmable load regulation. The reference voltage is modified, achieving a high DC gain, using a servo to remove any DC offset at the output of the switching converter. The correction implemented by the servo is measured, and a programmable fraction of the correction is injected back on either the reference voltage or the output feedback voltage. To accomplish at least one of these objects, a Buck, Boost, or other switching converter is implemented, consisting of an output stage driven by switching logic, with a servo configured between the reference voltage and the control loops of the Buck converter. The AVP function is implemented on either the reference voltage or output feedback voltage.

The present disclosure includes a method of charging a battery. In one embodiment, the method comprises receiving, in a battery charging circuit on an electronic device, an input voltage having a first voltage value from an external power source. The battery charger is configured to produce a charge current having a first current value into the battery. The input current limit and/or duty cycle of the charger is monitored. Control signals may be generated to increase the first voltage value of the input voltage if either (i) the input current limit is activated or (ii) the duty cycle reaches a maximum duty cycle. The charger also receives signals indicating a temperature inside the electronic device and generates control signals to decrease the value of the input voltage when the temperature increases above a threshold temperature.

An apparatus is disclosed for harvesting ringing energy. In an example aspect, the apparatus includes a bootstrap circuit. The bootstrap circuit includes a bootstrap capacitor and a bootstrap switch. The bootstrap switch includes a first terminal configured to accept an input voltage. The bootstrap switch also includes a second terminal coupled to the bootstrap capacitor. The bootstrap switch additionally includes a body diode comprising an anode coupled to the first terminal and a cathode coupled to the second terminal. The bootstrap switch is configured to be in an open state to charge the bootstrap capacitor via the body diode. The bootstrap switch is also configured to provide a voltage at the second terminal of the bootstrap switch. The voltage is greater than an average of the input voltage.

Methods and apparatus for detecting a zero inductor current to control switch transitions for a power converter. An example method includes outputting a first voltage and a first current, receiving the first voltage and output a second voltage into an input of a comparator, when the second voltage is above a third voltage, outputting a first output voltage, when the second voltage is below the third voltage, outputting a second output voltage, determining when the first current is zero based the output of the comparator, enabling a set of switches based on when the first current is zero.

An apparatus and a method for range extension for a combined data and power line are provided. Further, a bus system is provided. The design is based on a supply voltage that is transmitted via the combined data and power line being refreshed by a charge pump. Further, there may be provision, by way of example, for a data signal that is transmitted via the combined data and power line to be re-freshed using the likewise transmitted supply voltage.

In accordance with an embodiment, a method of controlling a switch driver includes energizing a first inductor in a first direction with a first energy; transferring the first energy from the first inductor to a second inductor, wherein the second inductor is coupled between a second switch-driving terminal of the switch driver and a second internal node, and the second inductor is magnetically coupled to the first inductor; asserting a first turn-on signal at the second switch-driving terminal using the transferred first energy; energizing the first inductor in a second direction opposite the first direction with a second energy after asserting the first turn-on signal at the second switch-driving terminal; transferring the second energy from the first inductor to the second inductor; and asserting a first turn-off signal at the second switch-driving terminal using the transferred second energy.

In accordance with an embodiment, a method of operating a switch-mode power supply includes receiving a measurement of a first current of the switch-mode power supply, determining a ripple of the first current based on the received measurement of the first current, determining a maximum current threshold based on a target average current and the determined ripple of the first current, determining an off time of a switch based on a target current ripple and the determined ripple of the first current, turning off the switch when the first current reaches the maximum current threshold, and turning on the switch after the determined off time has elapsed after turning off the switch.

In accordance with an embodiment, a method of operating a switch-mode power supply includes receiving a measurement of a first current of the switch-mode power supply, determining a ripple of the first current based on the received measurement of the first current, determining a maximum current threshold based on a target average current and the determined ripple of the first current, determining an off time of a switch based on a target current ripple and the determined ripple of the first current, turning off the switch when the first current reaches the maximum current threshold, and turning on the switch after the determined off time has elapsed after turning off the switch.