A 0.8V 4.3mW sub-harmonic mixer for ultra-wideband systems

A 6-10GHz 0.8V supply voltage low power consumption mixer for ultra-wideband (UWB) application is presented in this paper. The proposed mixer is based on a folded structure for the purpose of low supply voltage. Sub-harmonic technique is adopted to reduce LO signal frequency and suppress LO leakage signal which might appear in the input RF ports. The bias points of RF input stages are selected to be optimized for reducing the DC biasing current. Besides, -5dBm LO input power is chosen for low power consumption design. The proposed mixer is simulated with TSMC 0.18μm 1P6M CMOS process. The conversion gain of 6.4±2.8dB is achieved over the entire bandwidth. The LO to RF isolation is better than -120dBm within the operation frequency band of 4GHz. The maximum input third-order intercept point (IIP3) is -1.3dBm at 8GHz. The power consumption with output buffers is 4.3mW from a 0.8V supply voltage. The proposed mixer core only consumes 1.66mW. The chip size including I/O pads for further measurement is 0.904×1.102mm².