Voltage characteristics of the semiconductor diode diode anode: the P region as the anode electrode leads. Cathode: N district drawn by the cathode electrode. Point-contact diode, the current through a small, small junction capacitance for high frequency circuits and switching circuits. Surface contact type diode junction area, current, junction capacitance, suitable for low-frequency rectifier circuit. Planar diode junction area is larger by a large current, for high-power rectifier junction area is small, it can be used as a digital circuit switch. Divided by material germanium, silicon or gallium arsenide; by the structure a little touching, pn junction, pin, Schottky barrier, heterojunction; divided according to the principle of the tunnel, varactor, avalanches and step recovery. Mainly used for detection, mixing, parametric amplification, switches, regulators, rectifier and so on. After the development of optical communication, appear light, photoelectric, avalanche photodiodes, pin optoelectronics, semiconductor laser diodes. The most important characteristic of the diode is conductive in one direction. In the circuit, the current can only flow into the diode from the positive and negative outflow. Forward characteristic in an electronic circuit, the anode of the diode are connected to the higher potential side, a negative electrode connected to the low potential side, the diode will be turned on, DO35 diode, this connection, diodes, known as forward biased. Must state, when applied across the diode forward voltage is small, the diode is still not turned on, flows through the diode forward current is very weak. Only when the forward voltage reaches a certain value (this value is referred to as "threshold voltage", also known as the "dead zone voltage", germanium tube is about 0.1V, DO41 diodes, silicon tube of about 0.5V) after the diode can direct positive conduction. After the turn-on voltage remains substantially constant across the diode (germanium tube is about 0.3V, silicon tube of about 0.7V), the diode is called "forward voltage drop." Reverse characteristic in an electronic circuit, connected to the anode of the diode of the low potential side, a negative electrode connected to the high potential side, when the diode is almost no current flows through the diode in the OFF state at this time, this connection is called a reverse bias. When the diode is reverse biased, there will still be a weak reverse current flows through the diode, known as leakage current. When the reverse voltage across the diode increases to a certain value, in-line diode reverse current increases dramatically, the diode will lose one-way electrical properties, this state is called a diode breakdown. Varactor (Varactor Diodes), also known as 'varactor diode'. It is a use of PN junction capacitance (varactor barrier capacitance) and its inverse dependence of the main parameters of the diode and the principle of the bias voltage Vr is made: bias junction capacitance, zero bias merit, reverse breakdown voltage, reverse bias center, nominal capacitance, capacitance range (in units of picofarads) and cut-off frequency. Switching Diode _ gold credit (certified) _ diode provided by Qingdao integrity Technology Co., Ltd. Qingdao integrity Technology Co., Ltd. (www.qdjcx.com) is in Qingdao, Shandong diode leaders, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Ethical Leadership in gold with the staff warmly welcome all inquiries negotiations to create a better future gold credit.