Battery fuel gauge circuit

摘要

A detection circuit is mounted on an electronic device having a communication function, including at least a battery, a CPU, and a communication unit, and is configured to detect the remaining battery charge. An A/D converter performs sampling of a magnitude of a current IBAT discharged from the battery, and converts the current IBAT thus sampled into a digital current value. An interface circuit receives, from the CPU, control data which indicates a period in which there is an increase in the current discharged from the battery. Based upon the control data, a control unit raises the sampling frequency of the A/D converter in the period in which there is an increase in the current IBAT.

主权项

1. A detection circuit configured to detect a remaining battery charge of a battery, and to be mounted on an electronic device comprising at least the battery, a processor configured to integrally control the electronic device, and a communication unit, the detection circuit comprising:
an A/D converter configured to sample a magnitude of a current discharged from the battery, and to convert a magnitude of the current thus sampled into a digital current value; an interface circuit configured to receive, from the processor, control data which indicates a period in which there is an increase in current discharged from the battery; a control unit configured to raise a sampling frequency of the A/D converter based upon control data in the period in which there is an increase in the current; and an integrator circuit configured to integrate the current value acquired by the A/D converter so as to generate an integrated value and output the integrated value to the interface circuit, wherein the control unit judges whether the electronic device is in a non-communicating state or in a communicating state based upon the current value that corresponds to the battery current, and the interface circuit supplies the integrated value to the processor only while in the communicating state; and wherein the communicating state is a transmit period or receive period of the electronic device.