Dual band offset mixer for on-chip RF test in 0.13 μm CMOS

This paper discusses motivation and design of an offset mixer and investigates its optimum placement in loopback test setup for on-chip RF test. Based on this study, design and implementation of an offset mixer for on-chip RF testing of radio front ends is presented. The offset mixer is passive in nature reducing silicon area and power overheads. Mixer is implemented in 0.13 μm CMOS process and the design aims for dual band operation i.e. Bluetooth & WLAN standards and high linearity. Post layout results indicate that the mixer has excellent noise figure of 5 dB, low conversion loss of less than 5 dB as well as high IP3 of 12.5 dBm. Proposed passive offset mixer with almost zero dc power consumption and minimal silicon area makes it best suitable for on chip RF test. Pre & post-layout simulation results obtained with Cadence Spectre RF are presented.