Differential mixer with improved linearity

摘要

A mixing apparatus includes a Gilbert cell connected to a first load and a second load. In one embodiment each load contains transistors that are configured as a diode and a triode, where these circuits are additively combined to achieve substantially linear voltage-current characteristics over a predetermined range. The mixing apparatus takes two pairs of differential inputs and produces a pair of differential outputs. Because of the substantial linearity of the loads, the inputs and outputs of the mixing apparatus are acceptable over a relatively large range of input settings. In other embodiments each load may contain a transistor configured as a triode and a resistor, where these circuits are likewise additively combined to achieve substantially linear voltage-current characteristics over a predetermined range.