Characterization of Multiple Channels Room Temperature Readout Electronics for Large Transition-Edge Sensor Array

TL;DR

This paper presents a low-noise, high-resolution room temperature readout circuit for large TES arrays using TDM, achieving minimal noise contribution and high data transfer rates, suitable for scalable TES applications.

Contribution

Designed a compact, multi-channel room temperature readout electronics with ultra-low noise and high resolution, optimized for large TES array TDM systems.

Findings

ADC noise contribution is about 0.05 pA/√Hz above 100 Hz

ADC resolution exceeds 11.5 bits, ensuring distortion-free signal reconstruction

The readout board supports real-time data transfer at 2 Gbps per channel

Abstract

Transition-edge sensor (TES) is a highly sensitive device that is capable of detecting extremely low levels of energy. It is characterised by low noise performance and high energy resolution. A mature method for reading out TES signal is through time-division multiplexing (TDM) direct current superconducting quantum interference device (SQUID). In a TDM system, the signal readout chain represents a significant source of noise other than the TES intrinsic noise. The noise generated by TES is in the range of several tens to several hundreds of $pA/\sqrt{Hz}$. In order to ensure the high energy resolution of TES, it is necessary to ensure that the noise contribution from the room temperature readout electronics is less than $10$ $pA/\sqrt{Hz}$ above 100 $Hz$. In this work, we have designed a low-noise, high-resolution room temperature readout circuit for TDM. The equivalent current noise contribution of ADC is about $0.05$ $pA/\sqrt{Hz}$ above 100 $Hz$ and $0.46$ $pA\sqrt{Hz}$ under 30:1 multiplexing. The resolution of the analog to digital converter (ADC) is larger than 11.5 bits, which can reconstruct the TES signal without distortion. The readout board, which has eight channels, has JESD204B serial ports, which has greatly simplified the space of room temperature electronics. The readout chain is based on multi-threaded CPU processing and can transfer data at 2 $Gbps$ for each channel in real time. This readout board can be used in a TDM system with smaller size for large TES arrays.