Abstract:
A multi-phase switch mode, voltage regulator has a transient mode portion in which a phase control output is coupled to one or more control inputs of one or more switch circuits that conduct inductor current through one or more transient phase inductors, from amongst a number of phase inductors. A slew mode control circuit detects a high slope and then a low slope in the feedback voltage and, in between detection of the high slope and the low slope, pulses the phase control output of the transient mode portion so that the switch circuit that conducts transient phase inductor current adds power to, or sinks power from, the power supply output. Other embodiments are also described.
Abstract:
This disclosure relates to switch mode multiphase DC-DC voltage regulator circuits. In prior art regulators, for standard load transients, the worst voltage undershoot happens during a “zero to max,” i.e., “load step” operation. When the load is released, the inductor current ramps down, eventually crossing zero, where it is then held at a negative current limit (i.e., “NLIMIT”) by a Negative Current Limit Detector Circuit. However, if the next load step were to happen right at the instant when the inductor hits the negative current limit, it would take additional time recover to zero before it could catch up to the load step, thus causing additional voltage drop. Regulators disclosed herein comprise specialized zero crossing detection circuitry that intelligently prevents the inductor currents in one or more of the phases of the regulator from ramping below zero, thereby improving voltage droop in the system during fast positive load transients.
Abstract:
The switching frequency of a switch mode PFM power converter is compared with a predetermined frequency range that contains the operating frequency of a nearby clocked sub-system. In response to the switching frequency coming into the range, a parameter of the power converter is changed from an original value, so as to cause the switching frequency to go out of the range.
Abstract:
A power conversion circuit has multiple phases wherein each of the phases has an inductor coupled to a power switch circuit and is coupled to an output node. A power conversion controller controls the switching of one or more of the phases to yield a regulated voltage on the output node. The controller uses a variable inductor current limit for one or more designated phases, and temporarily increases the variable inductor current limit during a transient condition. Other embodiments are also described and claimed.
Abstract:
Power supply topologies can leverage relatively smaller component sizes while meeting the power requirements of loads. In a first stage, a determination is made as to whether a high current limit is exceeded for a first duration, or whether an average current provided exceeds an average current limit, such that a power supply component (e.g., inductor) is thermally stressed. In either event, a clock frequency is reduced by a first factor. In a second stage, a determination is made as to whether an output voltage drops below a voltage threshold. If so, the clock frequency may be further reduced by a second factor.
Abstract:
A multi-phase switch mode, voltage regulator has a transient mode portion in which a phase control output is coupled to one or more control inputs of one or more switch circuits that conduct inductor current through one or more transient phase inductors, from amongst a number of phase inductors. A slew mode control circuit detects a high slope and then a low slope in the feedback voltage and, in between detection of the high slope and the low slope, pulses the phase control output of the transient mode portion so that the switch circuit that conducts transient phase inductor current adds power to, or sinks power from, the power supply output. Other embodiments are also described.
Abstract:
The switching frequency of a switch mode PFM power converter is compared with a predetermined frequency range that contains the operating frequency of a nearby clocked sub-system. In response to the switching frequency coming into the range, a parameter of the power converter is changed from an original value, so as to cause the switching frequency to go out of the range.
Abstract:
A host electronic device may be coupled to an accessory electronic device. During normal operation, the host device may supply the accessory device with power over a power supply line. Back-powering events in which the accessory device delivers power to the host device may be prevented by interposing a protection transistor in the power supply line. A current mirror may be formed using the protection transistor and an additional transistor that produces a sense current proportional to the amount of current that is flowing through the power supply line. A current-to-voltage amplifier may produce a sense voltage that is proportional to the sense current. A bias circuit may be used to bias the sense current through the current mirror. A control circuit may compare the sense voltage to one or more reference voltages and turn off the protection transistor when appropriate to prevent back-powering of the host device.
Abstract:
The switching frequency of a switch mode PFM power converter is compared with a predetermined frequency range that contains the operating frequency of a nearby clocked sub-system. In response to the switching frequency coming into the range, a parameter of the power converter is changed from an original value, so as to cause the switching frequency to go out of the range.
Abstract:
A host electronic device may be coupled to an accessory electronic device. During normal operation, the host device may supply the accessory device with power over a power supply line. Back-powering events in which the accessory device delivers power to the host device may be prevented by interposing a protection transistor in the power supply line. A current mirror may be formed using the protection transistor and an additional transistor that produces a sense current proportional to the amount of current that is flowing through the power supply line. A current-to-voltage amplifier may produce a sense voltage that is proportional to the sense current. A bias circuit may be used to bias the sense current through the current mirror. A control circuit may compare the sense voltage to one or more reference voltages and turn off the protection transistor when appropriate to prevent back-powering of the host device.