Switching power supply with battery
AssigneeRF Micro Devices, Inc.
InventorsNadim Khlat, Alexander Wayne Hietala, Chris Ngo
Life of this patent
Estimating the term…
Abstract
The present invention relates to estimating a battery current supplied from a battery to a switching power supply, which provides a regulated output signal to a load, based on a switching power supply current in the switching power supply, and then controlling the regulated output signal to limit the battery current to within an acceptable threshold. The switching power supply current may be provided by one or more switching elements in the switching power supply. The switching elements may be mirrored to provide a mirrored switching power supply current, which is used to estimate the battery current. The estimated battery current may include an estimated average battery current, an estimated instantaneous battery current, or both.
Claims28
Switching power supply circuitry comprising:
- conversion circuitry comprising:
- a first buck transistor element configured to receive first battery current from a battery and provide a switching power supply current during a buck on phase of the conversion circuitry;
- a first boost transistor element configured to provide the switching power supply current during a boost on phase of the conversion circuitry, wherein the conversion circuitry is configured to provide a regulated output signal to a load based on the switching power supply current;
- and
- a first inductive element coupled between the first buck transistor element and the first boost transistor element;
- and
- control circuitry coupled to the conversion circuitry and configured to:
- generate a constant mirrored switching power supply current equal to the switching power supply current during the buck on phase;
- estimate an average battery current from the battery based on the switching power supply current and the constant mirrored switching power supply current to provide an estimated average battery current;
- and
- limit the regulated output signal based on the estimated average battery current to prevent the average battery current from exceeding an average battery current threshold.
A method comprising:
- receiving a battery current at a first buck transistor element;
- generating a switching power supply current via the first buck transistor element during a buck on phase and via a first boost transistor element during a boost on phase, wherein a first inductive element is coupled between the first buck transistor and the first boost transistor based on the battery current;
- providing a regulated output signal to a load based on the switching power supply current;
- sensing the switching power supply current using current sensing circuitry comprising at least a transistor generate a constant mirrored switching power supply current equal to the switching power supply current during the buck on phase;
- estimating an average battery current from the battery based on the switching power supply current and the constant mirrored switching power supply current to provide an estimated average battery current;
- and
- limiting the regulated output signal based on the estimated average battery current to prevent the average battery current from exceeding an average battery current threshold.
Dependencies are inferred from the claim text.