Abstract: The present invention discloses a battery module, a circuit board and an battery power optimization method. The battery power optimization method includes: activating a battery unit to cause the battery unit to discharge; obtaining a voltage value and a current value of the battery unit; and driving a heating unit to heat the battery unit according to the voltage value and the current value.

Abstract: An electronic device using near field communication is provided. The electronic device using near field communication includes a coil element, a display module, an antenna element and a switch element. The display module includes a panel. The antenna element is configured to transmit and receive a near field communication signal. The coil element, the display module and the antenna element are stacked. The coil element and the antenna element are at least partially overlapped. The switch element is connected to the coil element. The switch element is configured to switch the coil element into an open-loop state or a closed-loop state.

Abstract: A power management system including a first circuit board, a second circuit board and a connection cable is provided. The connection cable is compatible with USB type-C specification and connects the first circuit board and the second circuit board. When the first circuit board determines that a first power state of the first circuit board changes, the first circuit board transmits the first signal to the second circuit board through a configuration channel (CC) terminal of the connection cable, the second circuit board changes a second power state of the second circuit board according to the first signal.

Abstract: A power management system including a first circuit board, a second circuit board and a connection cable is provided. The connection cable is compatible with USB type-C specification and connects the first circuit board and the second circuit board. When the first circuit board determines that a first power state of the first circuit board changes, the first circuit board transmits the first signal to the second circuit board through a configuration channel (CC) terminal of the connection cable, the second circuit board changes a second power state of the second circuit board according to the first signal.