A 0.26 dB Noise-Figure 2.4 mW-Power Low-Noise-Amplifier with Auto-Tuned Pseudo-Resistors for Ionoacoustic Range Verification

Ionoacoustic detectors sense the weak signal emitted by the fast energy deposition of a proton beam through the energy absorber and exploit this detected signal to spatially measure the beam penetration depth or range, with promising application in hadron therapy treatment monitoring. However, clinical scenarios exhibit very weak acoustic signal power (tens of mPa) in 10 kHz - 1 MHz bandwidth. Therefore, it is of fundamental importance that the front-end amplifiers operate at very low noise levels (few nV/v Hz of in-band noise power spectral density) to minimize the degradation of the Signal-to-Noise Ratio (SNR). The Low-Noise-Amplifier (LNA) proposed in this paper operates in such a critical scenario, exploiting an advanced and dc-stable pseudo-resistor implementation to minimize noise power, achieving 0.26 dB of Noise Figure. The LNA has been designed in 28 nm CMOS technology, has a passband gain of 30 dB, an integrated noise power in the ionoacoustic bandwidth of 7.5 mu V-RMS and 2.4 mW power consumption.