Battery Management Scheme for NFC

摘要

There is described a method for establishing an NFC connection between a subscriber identity module (SIM) and an NFC device (RDR). The subscriber identity module (SIM) is connected to a telecommunications system (CELL_P) through contacts (VCC, RST, CLK, D+, GND, SWP, IO, D−) of the telecommunications system (CELL_P). The telecommunications system (CELL_P) comprises a chipset (CHP) and an NFC circuit (NFCC). The method comprises measuring the level of charge of a battery (BATT) powering the telecommunications system (CELL_P) with a battery gauge. Based on the measurement, the method selects the source for supplying power to the subscriber identity module (SIM) and configures the wiring of the subscriber identity module (SIM). The disclosure also relates, in particular, to a telecommunications system, to a computer program, and to a storage medium.

主权项

1. A method for establishing an NFC connection between a subscriber identity module and an NFC device, the subscriber identity module being connected to a telecommunications system through contacts of the telecommunications system, the telecommunications system comprising a chipset and an NFC circuit, the method comprising:
/a/ measuring the level of charge of a battery powering the telecommunications system with a battery gauge, /b/ if the measured level is greater than a threshold,
/b1/ powering the subscriber identity module through a first connection between a power supply contact of the telecommunications system and the chipset,/b2/ upon detection of an NFC device by the NFC circuit, establishing a connection between the subscriber identity module and the NFC device through the NFC circuit and a communications contact of the telecommunications system, /c/ if the measured level is lower than or equal to the threshold,
/c1/ applying a pull down on the first connection from the chipset and then configuring the first connection, from the chipset, in high impedance mode,/c2/ upon detection of an NFC device by the NFC circuit, powering the subscriber identity module from the NFC circuit through a second connection between said power supply contact and the NFC circuit, and establishing a connection between the subscriber identity module and the NFC device through the NFC circuit and said communications contact.