Reverse current prevention
AssigneeQUALCOMM Incorporated
InventorsLennart Karl-Axel Mathe, Joseph D. Rutkowski, Song S. Shi
Life of this patent
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Abstract
Techniques for preventing reverse current in applications wherein a tracking supply voltage is placed in parallel with a switching power stage. The tracking supply voltage may be boosted to a level higher than a battery supply voltage using, e.g., a boost converter. In an aspect, a negative current detection block is provided to detect negative current flow from the boosted tracking supply voltage to the battery supply voltage. A high-side switch of the switching power stage may be disabled in response to detecting the negative current. To prevent false tripping, the tracking supply voltage may be further compared with the battery supply voltage, and a latch may be provided to further control the high-side switch.
Claims20
An apparatus comprising:
- a high-side switch coupling a battery supply voltage to an inductor, wherein the inductor is further coupled to a tracking supply voltage;
- a low-side switch coupling the inductor to ground;
- and
- a negative current flow detection block configured to detect negative current flow from the tracking supply voltage to the battery supply voltage through the high-side switch, wherein the high-side switch is configurable to be disabled when negative current flow is detected.
A method comprising:
- selectively coupling a battery supply voltage to an inductor using a high-side switch, wherein the inductor is further coupled to an tracking supply voltage;
- selectively coupling the inductor to ground using a low-side switch;
- detecting whether there is negative current flow from the tracking supply voltage to the battery supply voltage through the high-side switch;
- and
- decoupling the battery supply voltage from the inductor using the high-side switch in response to at least one condition comprising the detecting the negative current flow.
An apparatus comprising:
- means for selectively coupling a battery supply voltage to an inductor using a high-side switch, wherein the inductor is further coupled to an tracking supply voltage;
- means for selectively coupling the inductor to ground using a low-side switch;
- means for detecting whether there is negative current flow from the tracking supply voltage to the battery supply voltage through the high-side switch;
- and
- means for decoupling the battery supply voltage from the inductor using the high-side switch in response to at least one condition comprising the detecting the negative current flow.
Dependencies are inferred from the claim text.