Diodes technetium Technology vulgarity diode characteristics

Switching diodes. Common PN junction diode switching diode has, PIN diodes and Schottky barrier diode, mainly used in computer, a variety of automatic control systems and microwave circuits. Switching diode switching time is mainly determined by the on-state to the OFF state of the transition period, this time known as reverse recovery time. From the beginning when reverse biased play reverse current drops to 1/10 of the initial value of time is called the reverse recovery time required. When the PN switching diode in the on state, the hole injection from the P region to the N region formed through the guide forward current, that when N-state area will always have a minority carrier storage. Plus after the reverse bias, only total exclusion of minority carriers stored in N region, the diode to the OFF state. PN switching diode reverse recovery time is mainly minority carrier storage time required is determined by the exclusion of N area. Incorporation of gold in silicon PN junction diode as recombination centers, can reduce the non-equilibrium minority carrier lifetime, thereby reducing the reverse recovery time, improve the switching speed. Technetium Guangdong Electronic Technology Co., Ltd. professional production and sales switching diode twenty years, the current switching diode 4148 into glass and plastic seals, the main package has: LL-34 (SOD-80 / MiniMELF), DO-34, DO-35 , ...... Schottky diodes advantage SOD-123, SOD-323, SOD-523, SOT-23, SOT-323 and so on: a high switching frequency and the forward voltage drop, etc., but the reverse breakdown voltage is relatively low mostly no higher than 60V, only up to about 100V, so as to limit its scope of application. As in switching power supplies (SMPS) and power factor correction (PFC) circuits in power switching device freewheeling diode, 100V transformer secondary with more frequency rectifier diode, RCD snubber circuit using high speed diodes and a 600V ~ 1.2kV PFC boost diodes with 600V, and only use the fast recovery epitaxial diodes (FRED), and ultra-fast recovery diode (UFRD). UFRD reverse recovery time of 20ns or more Trr are not sufficient to meet in areas such as the space station need to 1MHz ~ 3MHz with SMPS's. Even the hard-switching of 100kHz SMPS, due UFRD conduction losses and switching losses are large, the shell temperature is high, we need a larger radiator, so that the SMPS volume and weight gain, does not meet the miniaturization and light and thin trends. Therefore, the development of high voltage above 100V SBD, has been the subject people to study and attention. In recent years, SBD has made a breakthrough, 150V and 200V high-voltage SBD already on the market, the use of new materials in excess of 1kV SBD also successfully developed, so that their application has injected new vigor and vitality.