Circuit, method, and oximeter for indicating power supply by applying double-color light-emitting diode

A circuit, applied to a finger clip type pulse oximeter, for indicating a power supply by applying a double-color light-emitting diode (LED), characterized in that the circuit comprises:

• a micro-controller unit (MCU) module;
• a double-color LED module, including a double-color LED and connected to the MCU module;
• a voltage measurement module connected to the MCU module;
• a rechargeable battery module connected to the voltage measurement module;
• and
• a power supply input module, which is suitable for connection with an external power supply and is connected to the MCU module and the rechargeable battery module;
• wherein the MCU module is suitable for controlling the double-color LED according to the states of the power supply input module and the rechargeable battery module, so that the finger clip type pulse oximeter presents a visual result directly observable by the human eyes;
• wherein the power supply input module comprises a socket and a fuse, and the fuse is connected to the socket;
• wherein the circuit further comprises an insertion detection module, and the power supply input module is connected to the MCU module through the insertion detection module;
• and
• wherein the insertion detection module comprises a first resistor, and the first resistor is directly connected between an input/output (I/O) pin of the MCU module and the fuse.