PROJECT TITLE :

A 0.009–1.4-GHz Frequency Synthesizer With Suppressed Transients During VCO Band Switching

ABSTRACT:

This transient presents a zero.009–one.4-GHz frequency synthesizer that is able to make amends for changes within the frequency tuning vary, because of temperature variations, by switching voltage-controlled oscillator (VCO) bands with minimal phase and frequency errors, without cycle slipping and without introducing any phase offsets. This can be accomplished by a subthreshold capacitor bank switching circuit that causes the gradual addition of capacitance slowly enough to permit the loop to adjust the VCO management voltage to compensate. The additional circuitry uses less than 0.001 mm2 of silicon area and has minimal power consumption and minimal effects on the synthesizer's section noise when totally switched. The synthesizer used to demonstrate this was implemented in an exceedingly zero.eighteen-$mumboxm$ SiGe BiCMOS method and achieves 365-fs integrated jitter at 1.05 GHz, with a total power consumption of 81 mW. Measurements of the capacitor bank switching circuit shows that it prevents cycle slipping throughout band switching and reduces the most frequency deviation by 99.three%.