Tuned LNA for RFICs using boot-strapped inductor

In this paper, the principle of operation of a new type of active inductor and its application to a tuned LNA are described. The design is optimized at 1.8 GHz. An integrated transformer in connection with a current amplifier realizes a "boot-strapped" inductor with a L/spl times/Q factor never obtained before at this frequency. This way a selective LNA with a 60 MHz bandwidth, corresponding to a Q of 30, was designed. The circuit exhibits a matched noise figure of 1.8 dB with 25.5 dB transducer power gain while dissipating 20.7 mW from a 3 V power supply.