An 8-bit, 4-Gsample/s Track-and-Hold in a 67GHz fT SiGe BiCMOS technology

In this paper we present design and measurements of a high-speed track-and-hold (T&H) circuit. The circuit was implemented in a low-cost 67GHz f_T SiGe technology. At 4GS/s the circuit achieves SNR better than 52dB and THD of -50.5dB, corresponding to 8.1 effective bits. This performance is achieved for input frequencies up to 1.1GHz with a differential full-scale input swing of 0.9V_PP. The power dissipation of the T&H, including buffers and clock driver, is 590mW. Since measurements at such high frequencies are challenging, a full description of the measurement setup is provided