一种纳亨级电感测试仪

在通信链路和高频前端电路中，尤其涉及匹配滤波网络时，纳亨级电感的应用十分广泛．但是小量值电感的制作和测量极为困难，同时分布参数对通信机的影响也是非常难以评估和改善的．设计了一种简洁、低成本、高效的高精度纳亨级电感测量仪，包含ARM7主控制器、液晶显示模块、按键、DDS扫频模块、AGC模块、高频匹配检波器、电源、数字接口和其他信号调理电路．该仪器通过ARM7控制DDS产生扫频信号，寻找串联LC谐振回路的中心频率，从而计算补偿得到待测电感数值和其Q参数，并利用渐近式算法提高测量速度．该仪器能够测量1nH—10μH的电感值，并且能够提供10kHz-60MHz的频率的正弦波信号输出．总的来说，该仪器结构模块化，易于调试，并且能够提供良好的人机交互界面和数字通信端口，方便自动测量．

A measuring inductor on nH level

In recent years, inductors on nH level are widely used in communication lines and the front end circuit of high frequency, especially in the field of matching filter network. However, the manufacturing and measuring of small value inductors are still very difficult, and the influence of distributed parameters is hard to evaluate and improve. In this paper, a succinct inductors in high accuracy on nH level was designed with low cost and it was highly effective because of its precision in measuring. This design contained ARM7 main controller, LCD module, buttons, DDS frequency-sweeping module, AGC module, high frequency matching geophone, power source, digital interface and other circuits used for controlling. This equipment generated DDS frequency-sweeping signal under the control of ARM7 main controller, and then we could find the center frequency of LC series resonance to calculate the value of the certain inductor after compensation and its corresponding Q parameter. At the same time, we used progressive algorithm to raise the speed of measuring. This equipment could measure inductors from 1 nH to 10 μH and provide sinusoidal wave signal from 10 kHz to 60 MHz. This design was modularized and was easy to debug. Moreover, this equipment can also provide good human-machine interaction interface and digital communication port which provides automatic measurement.