A driving circuit selectively operates a hands-free loudspeaker and an earpiece speaker of a mobile terminal. The driving circuit includes a voiceband electronic circuit with a balanced output adapted for being switched between an in-phase and an opposite-phase mode, an interconnection function for connecting the earpiece speaker directly to the balanced output of the voiceband circuit, and an adder circuit for adding signals supplied by each port of the balanced output and for providing the sum-signal to the hands-free loudspeaker.