Design and Phase Noise Measurements of an Ultrafast Dual-Modulus Prescaler in 130 nm SiGe:C BiCMOS

The design complexity of high-speed and power-efficient circuits increases to higher operation frequencies. Therefore, this manuscript gives an overview of how to design and optimize fully differential emitter-coupled logic (ECL) gates using two dual-modulus prescalers with switchable division ratios of 4 and 5. The first prescaler is optimized to the highest operation frequencies, up to 142GHz and even 166GHz for the division ratios of 5 and 4, respectively. Furthermore, another prescaler has been optimized for the widely used 80GHz band, which has been heavily promoted by the automotive industry and has a high number of components in that domain. Both prescalers can be utilized in a fully programmable frequency divider with a wide division ratio range. As the measurement of the additive phase noise for frequency-converting devices with excellent noise performance is quite challenging, this is discussed theoretically and carried out practically. The measured jitter is between 500 as and 1.9 fs within integration limits of 100Hz up to 1MHz offset frequency.