Advantages, disadvantages, and packaging methods of Schottky diodes

Advantages, disadvantages, and packaging methods of Schottky diodes

Schottky diode is a semiconductor device that has three characteristics: low power consumption, high current, and ultra-high speed. It is made using the principle of metal semiconductor junction formed by the contact between metal and semiconductor, and medium and low-power Schottky diodes are generally packaged. Today, Jingdao Microelectronics Company will share with you:

The advantages of Schottky diodes are as follows:

1. Because the height of the Schottky barrier is lower than that of the PN junction barrier, the forward conduction and forward voltage drop of the Schottky diode are lower than those of the PN junction diode (approximately 0.2V lower).

2. Because SBD is a majority carrier conducting device, there are no issues with minority carrier lifetime and reverse recovery. The reverse recovery time of SBD is only the charging and discharging time of Schottky barrier capacitors, which is completely different from the reverse recovery time of PN junction diodes. Due to the very small reverse recovery charge of Schottky diode SBD, the switching speed is very fast and the switching loss is very small, making it particularly suitable for high-frequency applications.

Disadvantages of Schottky diodes:

The disadvantages of Schottky diodes are low reverse bias voltage and high reverse leakage current. For example, Schottky diodes made of silicon and metal have a rated withstand voltage of only 50V for reverse bias voltage, and the value of reverse leakage current is a positive temperature characteristic that easily increases rapidly with temperature. In practical design, attention should be paid to the hidden danger of thermal runaway. To avoid the above problems, the reverse bias voltage of Schottky diodes in actual use is much lower than their rated value. Of course, with the advancement of technology and Schottky diode technology, the rated reverse bias voltage will also increase.

Packaging form of Schottky diode:

Schottky diodes are divided into two packaging forms: lead and surface mount. Schottky diodes with lead type packaging are commonly used as high-frequency high current rectifier diodes, freewheeling diodes, or protective diodes. Schottky diodes have three pin extraction methods: common cathode (connecting the negative terminals of two diodes), common anode (connecting the positive terminals of two diodes), and series (connecting the positive terminal of one diode to the negative terminal of the other diode). It has two packaging forms: single diode and twin diode. Schottky diodes that use surface packaging come in various packaging forms such as single diode, double diode, and triple diode, with A to 19 pin extraction methods.