A low-voltage low-power active mixer

Abstract

The invention relates to a single-balanced active mixer that can work at a low power voltage. The active mixer comprises an alternating current coupling capacitor C0 of a radio frequency (RF) input signal (Vrf), a direct current bias resistor R0, an input tube N1 and a bias tube N0 thereof, and also comprises a metal oxide semiconductor (MOS) tube N2, an MOS tube N3, an MOS tube P2 and an MOS tube P3 that are used as loads. The N2 and P2 are connected to a positive local oscillator signal (Vlop) through capacitors C2 and C3. The N3 and P3 are connected to a negative local oscillator signal (Vlon) through capacitors C4 and C5. A P0 provides direct current bias for grids of load tubes P2 and P3. A resistor R1 provides bias for grids of the load tubes N2 and N3, and the bias resistor R1 and the bias tube N0 are in the same current path, so that the bias voltages of the N2 and N3 are slightly higher than that of the N1. Through adoption of the active mixer, the problem that the existing active mixer is hard to work at an extreme low voltage is solved, and the active mixer has lower power consumption.

Description

technical field [0001] The invention relates to a mixer in a radio frequency front end, especially an active mixer with low voltage and low power consumption, adopts CMOS technology, has great advantages in a low voltage digital-analog hybrid circuit, and has a simple structure, which is different from traditional mixers Compared with the device, it has lower power consumption when working at low voltage, and belongs to the field of integrated circuit design. Background technique [0002] With the advancement of CMOS integrated circuit technology, the size of MOS tubes is getting smaller and smaller, and the operating frequency is getting higher and higher. CMOS technology has been able to manufacture radio frequency circuits of several GHz or even more than ten GHz. On the other hand, the CMOS process is particularly suitable for manufacturing low-power digital circuits. Therefore, radio frequency circuits and digital circuits are often integrated into a single chip to form...

AI Technical Summary

Problems solved by technology

[0010] This expression must be established when the local oscillator signals Vlop and Vlon are ideal large-swing square waves, that is, N1 and N2 must work in the switch state, otherwise the gain will be significantly reduced, or even not working properly

However, as the RF frequency increases, the existence of various parasitic capacitances will seriously change the waveform of the signal, making it difficult for the square wave to exist, and it tends to be approximated as a sine wave by low-pass filtering; Large power consumption is not good for reducing power consumption

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