➀ The article introduces a reference design for a wearable heart rate monitor using a single 8-bit microcontroller and Phase Division Multiplexing technology to reduce noise and costs; ➁ The design utilizes Microchip's eXtreme Low Power 8-bit microcontroller with integrated features; ➂ The MCU includes digital-to-analog converters, operational amplifiers, and configurable logic cells to enhance performance and keep costs low.