Patent ID: 7418250

Claim:
A mobile terminal comprising: a quadrature mixer circuit comprising: an input terminal; a divider which divides a signal from said input terminal into substantially equal two parts, a first output signal and a second output signal; a first voltage-current converter to which a bias current is supplied from a first DC source and which converts the voltage of the first output signal from said divider into signal current; a second voltage-current converter to which a bias current is supplied from a second DC source and which converts the voltage of the second output signal from said divider into signal current; a local signal oscillator; a 90° phase shifter which outputs a local signal whose phase is substantially 90 degrees ahead or behind the phase of a local signal from said local signal oscillator; a first current switch circuit which switches on/off current output from said first voltage-current converter at timing of the local signal from said local signal oscillator; a first current-voltage converter which converts current output from said first current switch circuit into a voltage signal; a second current switch circuit which switches on/off current output from said second voltage-current converter at timing of the local signal output from said 90° phase shifter; and a second current-voltage converter which converts current output from said second current switch circuit into a voltage signal, wherein said quadrature mixer circuit includes an attenuator which attenuates signal current or voltage between a current output terminal of said first voltage-current converter and a current output terminal of said second voltage-current converter.