A CMOS harmonic rejection mixer based on current mirror amplifiers

Abstract

A harmonic rejection mixer (HRM) with current mirror amplifier for digital TV tuner applications is proposed. In the proposed HRM, gain ratio can be set accurately using the current mirror amplifier to achieve high harmonic rejection ratio without mismatch calibration circuits. Owing to a folded switching stage, a harmonic rejection ratio of the HRM is also immune to a supply voltage variation and the HRM can be designed at a lower supply voltage compared to a conventional HRM. A third and fifth-order harmonic rejection ratio of the proposed HRM are 52.6 and 50.8 dB. The harmonic rejection mixer consumes 11.5 mA from 1.5 V supply voltage.