USB-based portable outdoor multi-function tester design

With the development of society, outdoor measurements demand increased fast. The traditional test instruments due to their bulky, costly, inconvenience to carry, are not suited for outdoor operations. Based on this, this paper proposed a multi-function tester suitable for outdoor using. The instrument consists of data acquisition card with a USB interface, combined with notebook and LabVIEW. Self-made data acquisition card, using a low offset voltage, pre-stage analog conditioning circuits consist of the low bias current of high-accuracy operational amplifier OPA355 and 12-bit precision of high-speed pipeline type AD chip ADS802, and combined with USB interface, is easy to realize the data post-processing. So it effectively solved the bottleneck problem of data transfer rate, and can be powered via USB bus without need bulky power. This design has advantages of small size, light weight, low power, portable, low cost, excellent performance, and high flexibility. It has widely application prospect.