This application is developed by Sagi Kupferman AND Alon Yehezkely and relates to low-power transmitters operable by the Internet of things (IoT) devices. The newly developed application includes methods and devices for enabling a battery-free Bluetooth low energy communication. It also involves a transmitter and a reference voltage generator supplying a voltage to an oscillator circuit and has an oscillator circuit connected to a common-mode feedback circuit. Moreover, the device also includes an oscillator circuit including two pairs of semiconductor devices, wherein each pair of a semiconductor device comprises a device with a gate node connected to an antenna positive node interface.