A circuit of a system-on-chip for the transmission of an analog signal at a given transmission frequency modulated by a digital input signal coded in a number m of bits, includes 2m−1 unit cells each having a first block adapted to receive an activation voltage through an associated switch, and a second block with a first input path coupled to an output path of the first block, a second input path receiving a local oscillator signal, and an output path coupled to the output path of the circuit, with the switches each controlled as a function of the value of a bit of the digital input signal, the bit of index j of the digital input signal where j is between 0 and m−1, controlling the switches respectively associated with 2j unit cells.