A Power Efficient Gain Enhancing Technique for Current Mirror

This work introduces a new and simple method for adjusting the gain of current mirror. The major advantage of the proposed architecture is that, unlike the conventional variable gain current mirror, it does not need the change of the biasing current to adjust current gain. Therefore, the power dissipation remains constant in all of the gain settings. In addition, the proposed variable gain current mirror have linear-in-dB gain control characteristic, simple structure, and small occupied area. The gain of the current mirror can be simply varied from 1.3dB to 21dB while the 3-dB bandwidth of the circuit remains around 12.3MHz or 33.6MHz at operation frequency range of 1.9MHz-14.2MHz and 6.6MHz-40.2MHz respectively. The proposed circuit draws negligible power of 6.9µW from 1.8V supply voltage. The simulation results of designed variable gain current mirror in 0.18μm standard CMOS technology confirms the effectiveness of the proposed circuit.