A Capacitively Degenerated 100-dB Linear 20–150 MS/s Dynamic Amplifier

This paper presents a new dynamic residue amplifier topology for pipelined analog-to-digital converters. With an input signal of 100 mVpp,diff and 4× gain, it achieves -100-dB total harmonic distortion, the lowest ever reported for a dynamic amplifier. Compared to the state of the art, it exhibits 25 dB better linearity with twice the output swing and similar noise performance. The key to this performance is a new linearization technique based on capacitive degeneration, which exploits the exponential voltage-to-current relationship of MOSFET in weak inversion. The prototype amplifier is fabricated in a 28-nm CMOS process and dissipates only 87 μW at a clock speed of 43 MS/s, thereby improving the energy per cycle by 26× compared with that of state-of-the-art high-linearity amplifiers.