A multifunctional infrared (IR) module is configured for multiple IR applications without an additional microcontroller to be integrated into a computing device and is able to utilize voltage control instead of current control. The multifunctional IR module includes an IR light emitting diode (LED), and an IR receiver (e.g., photodiode or phototransistor). In one embodiment, the multifunctional IR module includes a resistor that is connected to the cathode of the IR LED and the drain of a transistor, with the source of the transistor grounded. In some embodiments, the multifunctional IR module additionally includes a red LED. Various configurations of the multifunctional IR module are able to perform one or more of the following functions: IR in (receiving IR signals), IR out (generating IR signals), heart rate sensing, SpO2 (oxygen saturation) sensing, distance/proximity detection, gesture detection, LED control, and ambient light detection.