公开(公告)号：US20210132017A1

公开(公告)日：2021-05-06

申请号：US16478623

申请日：2017-06-22

Applicant: ULSAN NATIONAL INSTITUTE OF SCIENCE AND TECHNOLOGY

Inventor： Jae Joon KIM ,  Subin CHOI ,  Kyeong-Hwan PARK

IPC: G01N33/00 ,  G01N27/04

Abstract: In a multi-channel resistance-based gas sensor system, the multi-channel array includes gas sensor channels respectively connected to resistive type gas sensors. The pre-processing unit selects one of a current mode, a resistance mode, and an external resistance mode, analyzes a sensing value obtained from any one of the gas sensor channels based on the selected mode and outputs a voltage value corresponding thereto. The ADC converts the voltage value to digital data. The control unit controls the pre-processing unit to execute one of the current mode for analyzing a sensing value smaller than or equal to a preset first resistance value, the external resistance mode for analyzing a sensing value greater than or equal to a preset second resistance value greater than the preset first resistance value and the resistance mode for analyzing a sensing value between the preset resistance first value and the preset second resistance value.

公开(公告)号：US20200052588A1

公开(公告)日：2020-02-13

申请号：US16655696

申请日：2019-10-17

Applicant: ULSAN NATIONAL INSTITUTE OF SCIENCE AND TECHNOLOGY

Inventor： Jae Joon KIM ,  Seungmok KIM ,  Kyeong-Hwan PARK

IPC: H02M3/156 ,  H03M3/04 ,  G01R27/00 ,  H03F3/45

Abstract: A differential mode converter that includes an input mode converter configured to convert an input voltage in a single-ended mode into a first differential voltage and a second differential voltage to be output, the first differential voltage and the second differential voltage being symmetric with respect to a reference voltage and having a form of a square wave; and a chopper configured to receive the first differential voltage and the second differential voltage and determine a first chopping voltage and a second chopping voltage based on the first differential voltage and the second differential voltage to output the first chopping voltage and the second chopping voltage, the first chopping voltage and the second chopping voltage being symmetric with respect to the reference voltage and having a form of a DC voltage.