Abstract:In response to the requirements for equipment temperature measurement in flight tests,a high-precision multi- channel temperature acquisition device suitable for flight tests is designed.The signal acquisition and processing system is built with FPGA,and AD8227 and AD590 are used to realize signal conditioning and temperature cold end compensation,which improves the accuracy and stability of the system.The 16—channel temperature signal transmission is realized through the standard RS422 protocol,and the output is nonlinearly corrected by linear fitting, which improves the accuracy and stability of the system.The test results show that the maximum measurement error in the full range of the temperature measurement circuit is±0.083%F.S..After testing and verification,the transmission process of this scheme has no frame loss and zero error code,and the system runs efficiently and reliably.