Abstract: Apparatus and associated methods relate to modulating a duty cycle in each of N interleaved power stages in response to determination whether a phase current is above or below an average of all phase output currents. In an illustrative example, the duty cycle modulation may increase or decrease delay on either the leading or trailing edges, which may fine-tune the phase PWM signal to correct the phase current to the average phase current. The modulation may be determined by comparing, for example, the voltage polarity across a resistor that extends between a signal representative of average phase current (IMON/N) and the corresponding phase current. By using the delay modulation engine, a power stage may locally and autonomously change the pulse width of a PWM signal to substantially balance phase currents among all of the interleaved power stages.

Abstract: Apparatus and associated methods relate to providing an integrated circuit package having (a) a bypass circuit in parallel with an inductor and (b) a logic circuit configured to control the bypass circuit for conductivity modulation. In an illustrative example, in response to a corresponding load transient, the logic circuit may include a state machine configured to generate different control signals for the bypass circuit to control the timing and/or quantity of energy transfer from the inductor to a load. The bypass circuit may include a first semiconductor switch and a second semiconductor switch connected in anti-series. In some implementations, the power stage and the bypass circuit may be operated, for example, in numerous operational modes to dynamically modulate conductivity across the terminals of the inductor in a power supply to advantageously result in a smaller undershoot and overshoot.

Abstract: Apparatus and associated methods relate to providing a power stage having an auxiliary power switch coupled to a high-side switch or a low-side switch in parallel and turning on the auxiliary power switch earlier than turning on the high-side switch. In an illustrative example, the auxiliary power switch may be connected with the high-side switch in parallel. The on-resistance of the auxiliary power switch may be greater than the on-resistance of the high-side switch. A gate drive engine may be configured to generate gate driving signals for the switches in the power stage such that the auxiliary power switch is turned on a predetermined time duration earlier than the high-side switch. Thus, the ringing at a switch node of the power stage may be advantageously reduced or eliminated.

Abstract: Apparatus and associated methods relate to providing a piecewise loadline having a number of segments with different slopes and selecting a segment of the piecewise loadline based on an output current of a power supply. In an illustrative example, the piecewise loadline may include a segment that has a negative slope. When the output current is less than a predetermined threshold, the segment with the negative slope may be selected to improve power efficiency. In some embodiments, the piecewise loadline may have several segments with different positive slopes. Different segments may be selected to make the load work in different modes. For example, by selecting an overcurrent loadline, the load (e.g., a processor) may be informed to throttle back its performance. Having a piecewise loadline may allow independent optimization of the loadline resistances, voltage thresholds, and current limits.

Abstract: Some apparatus and associated methods relate to conductivity modulation apparatus for active operations with an inductive element in a packaged circuit module formed with a bypass switch for configuration in parallel with an inductor. In an illustrative example, the bypass switch may be a controllable bidirectional switch formed of, for example, two anti-series connected MOSFETs. In some embodiments, the packaged module may include a main switch and/or a freewheeling rectifier (e.g., synchronous rectifier) operable as a buck-derived switched mode power supply. The bypass switch may, in operation, selectively circulate inductor current through the bypass switch, for example, to control the timing and/or quantity of energy transfer from the inductor to a load. In some implementations, the bypass switch may be operated, for example, to dynamically modulate conductivity across the terminals of an inductor in a buck-derived switched mode power supply to enhance circuit performance in numerous operational modes.

Abstract: Apparatus and associated methods relate to modulating the frequency of a switch signal to achieve a fast transient response while holding the average frequency constant over a predetermined number of N cycles. In an illustrative example, a quantum charge modulator may include a compensation processor configured to compensate an error signal and generate a compensation signal by performing operations to maintain an average switching frequency over the N cycles in response to the transient. The compensation signal may be a function of a real phase deviation ?TSW between a stable pulse modulated signal having a cycle period TSW before the transient and a measured pulse modulated signal having a cycle period TSW_M after the transient. A forgetting factor may be used to calculate the phase deviations. The quantum charge modulator may provide a compensation free, stable, and high performance response over power stage component changes.

Abstract: Some apparatus and associated methods relate to a three quarter bridge (TQB) applied across an output inductor of a buck-derived power converter, the TQB operated in a first mode such that when a high-side switch of the power converter is turned on, the TQB configured to pass a first controlled current to combine with a first output inductor current to a load, the TQB configured to control the first controlled current to minimize a negative voltage transient on the load, the TQB operated in a second mode such that when the high-side switch of the power converter is turned off the TQB configured to divert a second controlled current away from the load and to circulate the second controlled current through the output inductor, the TQB configured to control the second controlled current to minimize a positive voltage transient on the output of the power converter.

Abstract: Some apparatus and associated methods relate to a buck-derived switched mode power supply with three-quarter bridge (TQB) formed with a bypass switch in parallel with an inductor. In an illustrative example, the bypass switch may be configured to, in response to a decrease in average load demand, operate in a first mode to turn on the bypass switch to selectively circulate inductor current through the bypass switch while a high-side switch and a low-side switch are off. In a second mode, the bypass switch may be turned off to circulate the inductor current through, for example, an output capacitor and the low-side switch. In some implementations of the TQB, the bypass switch may be operated, for example, to selectively transfer a controlled amount of energy stored in the inductor to the output capacitor in response to a decrease in average load demand.

Abstract: Some apparatus and associated methods relate to a buck-derived switched mode power supply with constant on-time and configured to substantially maintain a steady-state average switch period in a time interval between a start of a load transient and the time when the inductor current returns to a steady state. In an illustrative example, the time interval may include a first and a second predetermined number of cycles after the start of the load transient. The switch period may be modulated, for example, by an amount calculated to supply a change in additional energy demand in the first number of cycles and an opposite amount in the subsequent second number of cycles calculated to maintain the average steady-state switch period over the time interval. In various examples, maintaining average switching period with constant on-time may minimize transient response times without sacrificing stability and without the need for complex compensation networks.

Abstract: Methods and apparatus relate to a minimizing ripple in a polyphase power supply by modulating a voltage pre-regulator output setpoint to minimize ripple performance. In an illustrative example, the modulation may include incrementally adjusting the pre-regulator output setpoint supplied, for example, to a multiphase controller. Some examples may reverse the increment direction in response to determining that the prior incremental adjustment yielded increased ripple. Each phase of the polyphase power supply may include a buck-derived switch-mode power supply connected, for example, to a common output node. Various embodiments may advantageously maximize reduce bulk capacitance requirements for active loads by dynamically seeking a duty cycle of the polyphase power supply with substantially minimal ripple.