Low flicker noise mixer and buffer. This design employs some native metal oxide semiconductor field-effect transistors (MOSFETs) (e.g., having no threshold voltage) within a passive mixer whose gates are driven using clock signals. These native MOSFETs maybe biased at one half of the power supply voltage to provide a lower noise figure. A cooperatively operating buffer employs appropriately places MOSFETs and resistors to ensure the desired gain. Relatively larger valued resistors can be employed to provide for higher voltage gain, and this can sometimes be accompanied with using a higher than typical power supply voltage. Source followers serve as output buffers and also ensure the required output DC voltage level as well. It is also noted that this design can be implemented using n-channel metal oxide semiconductor field-effect transistors (N-MOSFETs) of p-channel metal oxide semiconductor field-effect transistors (P-MOSFETs).