Kim Chang-Hyeon, Yang Ki-Hoon, Song Yeon-Seob, Yoo Sang-Sun, Pu Younggun, Kim Il-Hwan, Chung Seok-Whan, Choi Kwang-Wook, Park Jun-Eun, Lee Kang-Yoon
Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Samsung Advanced Institute of Technology, Suwon 16706, Republic of Korea.
Sensors (Basel). 2024 Jun 26;24(13):4149. doi: 10.3390/s24134149.
This paper proposed a fine dust detection system using time-interleaved counters in which surface acoustic wave (SAW) sensors changed the resonance point characteristic. When fine dust was applied to the SAW sensor, the resonance point decreased. The SAW oscillator made of the SAW sensor and radio frequency (RF) amplifier generated an oscillation frequency that was the same as the resonance frequency. The oscillation frequency was transferred to digital data by a 20-bit asynchronous counter. This system has two channels: a sensing channel and a reference channel. Each channel has a SAW oscillator and a 20-bit asynchronous counter. The difference of the two channel counter results is the frequency difference. Through this, it is possible to know whether fine dust adheres to the SAW sensor. The proposed circuit achieved 0.95 ppm frequency resolution when it was operated at a frequency of 460 MHz. This circuit was implemented in a TSMC 130 nm CMOS process.
本文提出了一种使用时间交错计数器的细粉尘检测系统,其中表面声波(SAW)传感器改变了共振点特性。当细粉尘施加到SAW传感器上时,共振点降低。由SAW传感器和射频(RF)放大器组成的SAW振荡器产生与共振频率相同的振荡频率。振荡频率通过一个20位异步计数器转换为数字数据。该系统有两个通道:一个传感通道和一个参考通道。每个通道都有一个SAW振荡器和一个20位异步计数器。两个通道计数器结果的差值就是频率差。通过这个,可以知道细粉尘是否附着在SAW传感器上。所提出的电路在460MHz频率下工作时实现了0.95ppm的频率分辨率。该电路采用台积电130nm CMOS工艺实现。