The HMC1061LC5 is a SiGe monolithic, fully differential, dual rank, track-and-hold (T/H) that provides unprecedented bandwidth and dynamic-range performance to wideband sampled signal systems. The T/H offers precision signal sampling over 18 GHz bandwidth, with 9 - 10-bit linearity from DC to beyond 5 GHz input frequency, 1.5 mV noise, and <70 fs random aperture jitter. The device can be clocked to 4 GS/s with minimal dynamic range loss. The T/H can be used to expand the bandwidth and/or high-frequency linearity of high-speed A/D conversion and signal acquisition systems.