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).