Friends in the electronic components industry know that Schottky diodes are widely used and have a very high market share. In the process of receiving customers, customers will consult some related questions, both conventional and special. Today we have compiled two frequently asked questions about Schottky diodes for your reference only.
Question 1: The difference between Schottky diodes and triodes.
Answer: Schottky diodes, also called Schottky barrier diodes, are low-power, ultra-high-speed semiconductor devices. Schottky diodes use metal and semiconductor contacts to form a metal-semiconductor junction. It has the characteristics of large rectifying current, fast speed, short reverse recovery time, and reduced forward voltage. It is often used as a freewheeling diode in switching power supplies. The most notable feature of Schottky is that the reverse recovery time is extremely short (can be as small as a few nanoseconds), and the forward voltage drop is only about 0.4V. In the case of the same current, its forward voltage drop is much smaller.
In the industry, there is no real Schottky transistor. The so-called Schottky transistor is actually a combination of a Schottky diode and an ordinary transistor, which can improve some of the performance of the transistor. The Schottky transistor can effectively limit the saturation depth of the tube and greatly shorten the switching time. When the transistor is not saturated, Jc is reverse biased and SBD is off, which has no effect on the circuit; when the transistor is saturated, Jc is forward biased and SBD is turned on, so that the collector forward bias is clamped at 0.4V, limiting the saturation depth of the tube , While reducing the base current of the triode.
Question 2: Why do switching power supplies use Schottky diodes?
Answer: The reason why the switching power supply chooses Schottky diodes is mainly because the use of Schottky diodes as rectifiers can increase the switching frequency on the one hand and improve efficiency on the other. However, another common usage of Schottky diodes is to make clamp diodes at the output end, which is mainly used for its short reverse recovery time and rapid clamping and timely clamping; and the use of its small forward voltage drop, which affects the clamping voltage. small. Moreover, Schottky diodes have short reverse recovery time and fast speed, and are often used for switching power supply rectification.
The high utilization rate of Schottky diodes is inseparable from its product performance. These two issues explain the performance of Schottky diodes and make customers more convinced.