DC Parameter Test System 개발

The Development or DC Parameter Test System

In this paper, we developed the DC parameter svstem which inspects the property of DC parameter for semiconductor products. The conventional system has complex hardware. Also the interfacing with IBM-PC is hard because that was almost materialized by analogy circuits. The proposed system is interfaced by IBM-PC. It is consisted of CPLD (Complex Programmable Logic Device) part, ADC (Analogue to Digital Converter), DAC (Digital to Analogue Converter), voltage/current source, variable resistor and measurement part. In the proposed system, we have designed the constant voltage source and the constant current source in a part. The CPLD part is designed by VHDL (VHSIC Hardware Description Language), which it generates the control and converts the serial data to parallel data. Voltage source part generates analogue test voltage and maintains that one. Current source part generates the analogue test current and maintains the current. ADC part converts analogue data to 16 bits digital data. DAC part converts the 12 bits digital test voltage to analogue voltage. Variable resistor is the part for the controlling the range of current. The proposed DC parameter test system has two test channels and it operates VFCS (Voltage Force Current Sensing) mode and CFVS (Current Force Voltage Sensing) mode. The normal resistor with error range ±5% and diode is tested. When the normal resistor testing about 10% error is measured. When the diode testing about 7% error is measured.