An MICS band frequency synthesizer using active inductor and auto-calibration scheme

An MICS band fractional-N frequency synthesizer using active inductors and auto-calibration technology is presented in this work. The active inductors and capacitors of the loop filter were implemented with MOSFET for decreasing the phase noise and silicon area. Moreover, the proposed auto-calibration technique would reduce and overcome the effect of voltage, temperature, and process variations. This chip was fabricated in 0.18 μm CMOS process. The measurement results show that the proposed 402–405 fractional-N PLL occupies a core area of 450×385 μm2. The phase noise is −105.5 dBc/Hz at 1 MHz. The power consumption is 5.13 mW at 402 MHz.