A Microprocessor-Based Solar Cell Test System

The electrical behavior of a solar cell is completely characterized by its current versus voltage (I-V) curve. To obtain this curve, the voltage across the solar cell may be continuously or discretely varied and the corresponding voltage and current variations plotted on an X-Y plotter. However, accuracy, speed, and convenience requirements make it highly desirable to have an automated I-V curve measurement system with a digital readout. A microprocessor-based solar cell measurement system is described in this paper. The hardware is composed of an INTEL-8080A-based microcomputer, a 12-bit D/A converter, a 12-bit A/D, and two Op Amp's serving as driver and sensor. The software is designed to be modular to facilitate documentation and future program modifications. The main advantages of this solar cell test system are high accuracy, high speed, and a reasonable cost.