Method and apparatus for reducing common mode variations in a voltage sensing component
AssigneeQUALCOMM Incorporated
InventorsBaiying Yu, Brett C. Walker
Life of this patent
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Abstract
A method and apparatus that reduce common mode variations experienced by a voltage sensing component. A measurement component such as a BATFET or an external sensing resistor, receives, at its source, a voltage from the top of a battery having a voltage VPH_PWR. A voltage sensing component, such as an ADC, is powered by the voltage from the battery. A power referenced component, such as a power referenced LDO, tracks the voltage from the battery and outputs the tracked voltage minus a predetermined voltage amount to a negative side of the voltage sensing component.
Claims20
An apparatus for reducing Common Mode variations experienced by a voltage sensing component, the apparatus comprising:
- a battery having a voltage VPH_PWR;
- a measurement component that receives, at its source, a voltage from the top of the battery;
- a voltage sensing component powered by the voltage from the battery;
- and
- a power referenced component that tracks the voltage from the battery and outputs the tracked voltage from the battery minus a predetermined voltage amount to a negative side of the voltage sensing component.
A method of reducing a common mode variation experienced by a voltage sensing component, the method comprising:
- receiving a first voltage from a battery at a source of a measurement component, wherein the first voltage is received from the top side of the battery;
- outputting a second voltage from the measurement component to a power referenced component, wherein the second voltage tracks the first voltage;
- outputting a third voltage from the power referenced component to a voltage sensing component, wherein the third voltage is equal to the second voltage less a predetermined voltage amount;
- and
- powering the voltage sensing component between the first voltage and the second voltage.
Dependencies are inferred from the claim text.