Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC...Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain.展开更多
A novel phase-locked loop( PLL)-based closed-loop driving circuit with ultra-low-noise trans-impedance amplifier( TIA) is proposed. The TIA is optimized to achieve ultra-low input-referred current noise. To track driv...A novel phase-locked loop( PLL)-based closed-loop driving circuit with ultra-low-noise trans-impedance amplifier( TIA) is proposed. The TIA is optimized to achieve ultra-low input-referred current noise. To track drive-mode resonant frequency and reduce frequency jitter of actuation voltage,a PLL-based driving technique is adopted. Implemented on printed circuit board( PCB),the proposed driving loop has successfully excited MEMS element into resonance,with a settling time of 3 s. The stable frequency and amplitude of TIA output voltage are 10.14 KHz and 800 mVPP,respectively. With sense-channel electronics,the gyroscope exhibits a scale factor of 0.04 mV/°/s and a bias instability of 57.6°/h,which demonstrates the feasibility of the proposed driving circuit.展开更多
文摘Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain.
基金supported by the National Natural Science Foundation of China (grant: 61234007)the subproject of the Very Large Scale Integrated Circuits Manufacturing Equipment and Complete Technology (No.2 National Major Projects of China) (No.: 2013ZX02502-001)
文摘A novel phase-locked loop( PLL)-based closed-loop driving circuit with ultra-low-noise trans-impedance amplifier( TIA) is proposed. The TIA is optimized to achieve ultra-low input-referred current noise. To track drive-mode resonant frequency and reduce frequency jitter of actuation voltage,a PLL-based driving technique is adopted. Implemented on printed circuit board( PCB),the proposed driving loop has successfully excited MEMS element into resonance,with a settling time of 3 s. The stable frequency and amplitude of TIA output voltage are 10.14 KHz and 800 mVPP,respectively. With sense-channel electronics,the gyroscope exhibits a scale factor of 0.04 mV/°/s and a bias instability of 57.6°/h,which demonstrates the feasibility of the proposed driving circuit.
