ESD Voltage Generator Based On CPLD

In the day-to-day activities, the human body can get the charge through contact, separation, and the friction process.when people use their fingers, which are charged with electrons to touch an electrical device or electrical system, the Electro-Static discharge through the path between human body and electrical device. There are high voltage pulse and high current pulse forced on electrical device when Electro-Static discharge (ESD) happens. These high voltage and current is fatal to the electrical device, which take perpetuity destroys to electrical device. As technology in integrated circuit(IC) continues to scale, the diagnostic size has been decreased significantly. As a result, the gain of MOSFET has lower reverse voltage tolerance. Therefore, ESD becomes more and more important and needs to be handled as a key problem in the IC chips'manufactured and using. As described above, to go deep into the mechanism of ESD, and find new method to protect electrical device from ESD, the study on ESD Model and design of the ESD voltage generator are extraordinarily significant.In this thesis, a high voltage generator for ESD testing is designed with ordinary electronic device according to IEEE standard. The main work mentioned in this thesis is design of a new Electrostatic Discharge (ESD) generator based on CPLD. The design incorporates a CPLD as the key controller, fly-back transformer as high voltage DC source and serial connection of SCR as high voltage switch. And results show that, the generator expressed in this paper has reached its limited voltage at 8kV. During the whole 200ns discharge circle, setup time is less than 20ns, which accord with IEEE STD C62,38-1994. Additionally, this generator produces high voltage automatically for certain times. These times are less than 999, which depend on the number set by costumer. If it's necessary, every interval between two discharge pulses is alterable. Since the components of this instrument are easy to get, and the price is pretty low, so the entire generator is inexpensive and friendly to operate.