A CMOS 90 nm 55 mW 3.4-to-9.2 GHz 12 Band Frequency Synthesizer for MB-OFDM UWB

A frequency synthesizer for ultra-wideband (UWB) multiband orthogonal frequency division multiplexing (MB-OFDM) applications is designed in TSMC 90 nm CMOS technology. It is based on two wideband PLLs (8 MHz open loop unit gain frequency) capable of settling in less than 300 ns with a 66 MHz external reference. The PLL tuning range (6.6-9.2 GHz) is extended down to 3.4 GHz by a dedicated circuit able to divide the output frequency by 1, 1.5 and 2 with a power consumption of less than 3 mW. Measured data fit the UWB MB-OFDM specifications with an integrated phase noise of 2.8_RMS ^o at maximum output frequency and an aggregate spurious tone power of less than -27 dBc. The joint power consumption is 55 mW and the synthesizer core area occupies less than 0.5 mm² .