A CMOS Image Rejection Mixer for DAB/DMB Low-IF Tuner IC Exhibiting 41dB Adjacent Channel Rejection Ratio

The image rejection mixer for digital audio broadcasting and digital multimedia broadcasting (DAB/DMB) is described. The mixer is implemented in a 0.18mum six-layer metal CMOS process and occupies a 2.25mm
²
. To obtain the ultimate level of image rejection without additional tuning, the double quadrature architecture is used and to linearize the RF buffer, differential transconductance linearization technique is used (Tae wook Kim, et al., 2005). The fabricated mixer exhibits 65 dB image rejection ratio, 41dB adjacent channel rejection ratio, 100 kHz ~ 1.65MHz image rejection bandwidth, 16dB gain, 35dBmV input-referred third order intercept point (IIP3), and 15mA current consumption from 1.8V supply