A mixer apparatus (60), such as an integrated circuit (IC) mixer is provided for improving the physical layout of devices containing mixers. The mixer includes a multiplier (62) with an input port (64), an output port (66), a first switchable local oscillator input port (68) and a second switchable local oscillator input port (72). The dual switchable local oscillator ports are located on either side of the mixer, between the input side and the output side. The dual switchable local oscillator ports allow the mixer to provide more flexibility in integrated circuit and printed circuit board design layouts involving mixer apparatus. For example, in dual channel devices, a local oscillator can be coupled to a pair of the mixers using transmission lines that do not have to be routed around the integrated circuit, to a different level of the printed circuit board or underneath one of the mixers.