77 K下碲镉汞APD探测器的高精度时间数字转换电路

碲镉汞雪崩光电二极管(HgCdTe APD)是目前红外焦平面技术前沿研究之一,低温下高精度时间标记读出电路是APD焦平面的基础,直接影响到APD红外焦平面性能.时间数字转换电路(TDC)是实现高精度时间标记的方法之一.基于对低温下金属-氧化物半导体场效应晶体管(Metal-Oxide-Semiconductor Fie...

High precision time-to-digital conversion circuit for mercury cadmium telluride APD detector at 77 K

HgCdTe avalanche photodiode(APD)is the frontier research on infrared focal plane technology.High-precision time stamp's readout circuit is the basis of the APD focal plane at 77 K,which directly affects APD infrared focal plane performance.Time-to-digital conversion circuit(TDC)is one of the methods to achieve high-precision time stamping.Based on the analysis of MOSFET device at low temperature,we design a vernier TDC circuit,which uses a synchronous counter to quantize an integer multiple of the periods to achieve a coarse count of 6 bits.We use the highfrequency clock multiplied by the on-chip phase-locked loop to quantify the part that is less than one clock cycle to achieve a fine-count of 6 bits output.The circuit adopts standard CMOS process tape out,and our circuit works at a master-frequency of 120 MHz.At 77 K,the circuit tests can distinguish the time resolution of 236.280 ps.The DNL is within-0.54~0.71 LSB,and the INL is within-1.32~1.21 LSB.