A broadband transceiver ASIC for X-nuclei NMR spectroscopy in 0.13 µm BiCMOS

In this paper, we present a fully-integrated transceiver ASIC (NMR-on-a-chip) for multi-nuclei nuclear magnetic resonance (NMR) measurements with operating frequencies up to 770 MHz. The NMR-on-a-chip transceiver co-integrates a low-IF receiver, consisting of a low-noise amplifier, quadrature down-conversion mixers followed by intermediate-frequency variable gain amplifiers, a power amplifier, and a frequency generation block. The ASIC is realized in a 0.13 µm SiGe BiCMOS technology and occupies a total chip area of 1100×900 µm ² . The power amplifier has a maximum peak-to-peak output current of I TX,pp = 210 mA. The receiver chain has a maximum conversion gain of A RX = 66 dB with a minimum input-referred noise of ${v_{{\text{n,min}}}} = 610{\text{ pV}}/\sqrt {{\text{Hz}}} $. The chip performance is also verified in the target NMR application, in which the presented system achieves a state-of-the-art normalized spin sensitivity of $8.3 \times {10^{17}}{\text{spins}}/\sqrt {Hz} \cdot {{\text{T}}^2}{\text{m}}$.