To provide a mixer circuit with low noise that is operated at a low voltage by acting a MOS transistor(TR) like a 4-terminal device without the need for a load placed between a fixed voltage source and a source terminal.

The circuit is a 4-terminal multiplier circuit that mixes up to three input signals. This circuit includes a MOS TR having a gate, a source, a drain and a back gate terminal. In the case that this circuit is used for an RF mixer, that is, a low frequency converter, an RF signal is fed to a gate terminal 126, a local oscillator signal is fed to th back gate terminal 130, a DC voltage is fed to th source terminal 124 to provide a bias to the TR and a mixed/low frequency converted output (IF) signal is obtained from the drain terminal 128. In a single balanced circuit, two MOS TRs are in use and noninverting and inverting IF signals are obtained.