Method and apparatus for temperature adjusted control of BATFET current sensing

摘要

A method and apparatus for providing a temperature sensing loop used in connection with a current sensing component, such as a BATFET, in order to compensate for variations in the BATFET's resistance due to temperature variations. The temperature sensing loop detects a temperature of the BATFET and regulates the gate voltage of the BATFET based on the detected temperature in order to compensate for changes in the BATFET's resistance. The temperature sensing feedback loop maintains the BATFET at a constant resistance for current sensing through negative feedback control. The BATFET and temperature sensing loop can be provided as components of an on-chip fuel gauging application for a UE.

主权项

1. An apparatus for temperature adjusted control for a current sensing component, comprising:
a current sensing component inserted in a voltage line, wherein the current sensing component measures current in the voltage line; and a feedback loop component that tracks a temperature of the current sensing component and modulates a resistance of the current sensing component based on the tracked temperature wherein the current sensing component comprises one of a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) and a Battery Field-Effect Transistor (BATFET), and further wherein the current sensing component comprises a BATFET, and wherein the feedback loop component detects a temperature of the BATFET and modulates a gate voltage of the BATFET based on the detected temperature, and further wherein the BATFET receives a first voltage in the voltage line, and wherein the feedback loop component comprises: a BATFET replica that receives the first voltage and outputs a second voltage; a programmable resistor that receives the first voltage and outputs a third voltage; an error amplifier that receives the second voltage and the third voltage and outputs a fourth voltage; and a second amplifier that receives the fourth voltage and outputs a fifth voltage to a gate of the BATFET.