基于PXI总线的24通道高精度铂热电阻模拟板设计

Design of 24 Channel High Precision Platinum Resistance Breadboard Based on PXI-bus[HS)]

摘要:

针对市场上现有模拟铂热电阻的不足,使用数字电位器和精密电阻设计了一款基于PXI总线的24通道高精度铂热电阻模拟板——PXI5440;依据误差传递原理对设计进行了误差分析,结果表明:更换精密电阻可调整铂热电阻输出范围,但不影响其输出精度；输出电阻越大,数字电位器步长对输出电阻精度的影响将减小,输出电阻的绝对误差将减小;同时,给出了软件驱动函数算法,实际测量结果,证明了设计思路的正确性,理论的正确性;本产品同市场上现有产品相比,其具有价格低、通道个数多及精度高等优点。

Abstract:

Aiming at the deficiency of simulation platinum thermal resistance in current market, we design a 24 channel high precision platinum resistance breadboard—PXI5440 using digital potentiometer and precision resistance.We analyse the error on the basis of error propagation, and the results confirmed that:The replacement of precision resistance can adjust the output range of the platinum resistance, and it will not affect the output precision of the resistance; The greater the output resistance, the lesser it will affect on the precision of output resistance, and the absolute error of the output resistance will decrease. We give the driving function algorithm and the actual measurement results,which prove the correctness of the design ideas and theory. Compared with the existing products on the market, the breadboard of platinum thermal resistance in this paper,has the characteristics of low price、multi-channel and high precision.