A Low Noise Voltage Controlled Active Inductor with Simultaneously Enhanced Q-Frequency Characteristics
A novel low noise voltage controlled active inductor(VCAI)with simultaneously enhanced characteristics of Q-frequency was proposed.It mainly consisted of four modules,which was a dual feedback loop,a feed-forward branch,and two current mirrors.Among them,the dual feedback loop was used not only to form a gyrator to achieve inductance characteristics,but also to generate negative resistance to improve the Q value,and furthermore was configured with two voltage control terminals to adjust the inductance L value and Q value.And the two current mirrors were configured with two external voltage control terminals to provide DC bias and to further adjust L value and Q value.The feed-forward branch was connected to the positive transconductor of the gyrator to reduce the noise.Finally,both the cooperation of four modules and the joint regulation of the four control terminals made the VCAI not only achieve independent adjustment of the Q peak values relative to the L values at the same frequency,but also maintain the Q peak values basically unchanged at different frequencies,and also have low noise.The verification results indicate that at 3 GHz,the Q peak values can be significantly tuned from 135 to 1 132,while the L value only slightly changes from 43.50 nH to 43.89 nH.At 2 GHz,3.4 GHz,and 5 GHz,the Q peak values are 682,659,and 635,respectively,with a change rate of only 6.8％.At 1 GHz,the input reference noise voltage of VCAI is 3.2 nV/√Hz,which is 6 nV/√Hz lower than 9.2 nV/√Hz for the AI without a feed-forward branch.
NETL
NSTL
万方数据
