What are the differences: rectifier diode, Zina diode, and Schottky diode?

Technical Blogs|Technical Blogs|

2022-03-17 18:34:59 92

A diode is a passive device that allows current to flow in one direction. Because there are too many types of diodes, they should be selected according to the circuit requirements. This article tells about three kinds of widely used diodes: rectifier, Schottky diode and Zener diode and when to use them.

attribute	definition
Vf	Indicates the forward voltage drop when the current flows from the P terminal to the N terminal of the diode.
If	Maximum forward current of diode
VR	Reverse breakdown voltage when current flows from N terminal to P terminal.
IR	The amount of current flowing when the diode is reverse biased.
tRR	When the diode is suddenly turned off, it takes a short time for the forward current flowing through the diode to disappear, which is called the reverse recovery time.

一、Rectifier diode:

? Rectifier diode is the simplest p-n junction diode, which is mainly used for half-bridge and full-bridge rectifiers. The breakdown voltage is very high, usually in the order of 200 to 1000 volts.

?The forward voltage drop (Vf) of the rectifier diode is between 0.7V and 0.9V.

af6d1f8a9904b106d3e562c24df38150

For example, design a bridge rectifier for an AC-DC converter. For this bridge rectifier, 1N4 rectifier diode is the best choice.

1a3fee3a1ac0c889cf2d03d3a80a75a4

二、Schottky diode

? Unlike the rectifier diode, the junction of Schottky diode is located between the N-type semiconductor and the metal plate.

? Schottky diodes, also known as barrier diodes, are mainly used in low-voltage circuits because the forward voltage drop (Vf) of Schottky diodes is smaller than that of rectifier diodes. Typically in the range of 0.25 V to 0.5V .

08801a85c2f8827b0987624ec6de74d5

? In Schottky diodes, electrons are the main charge carriers on both sides of the junction. Therefore, it is a unipolar device.

? Mainly used in high frequency applications, such as SMPS. Low temperature rise, high switching speed and short recovery time.

d604b396210f3b3afa36531be9e431cc

? One disadvantage of Schottky diode is its low breakdown voltage (20v to 40v), so it is not suitable for rectifying circuit.

Note: Compared with ordinary rectifier diodes, the reverse recovery time of Schottky diodes is much shorter, making it suitable for fast switching circuits. Disadvantage of Schottky diode

?Suppose a buck converter is designed, and the Mosfet in this circuit switches at a very high frequency, so the diodes required in this circuit should have a high switching speed, and Schottky diode is the best choice.

43f8f52e603c4873d765f8c999171b42

三、 zener diodes

? Zener diode is composed of p-n junction, but it is heavily doped compared with ordinary diode. So that it can be broken down without being damaged.

? Because of this characteristic, Zener diodes are used as voltage regulators in electronic circuits.

? Zener diodes are never used for rectification purposes.

b6cc7c9b7acda65b8a9ace692dd56bb8

? A circuit that uses a zener diode to prevent the MOSFET gate from being damaged by cutting off the input voltage. The breakdown voltage of the zener diode is 5.1V.

f09ee34dd28f6e23679ecab924bbdddf

? If the voltage of MOSFET gate unexpectedly exceeds 5v, diode breakdown will occur, and all current will flow to the ground through the diode. Thereby preventing the MOSFET from being damaged in any form.

? This is another circuit, where two diodes are connected facing each other's P terminals. If an AC signal is supplied at the input, one diode will clip the voltage to the positive half, while the other diode will clip the voltage to the negative half. Therefore, we get a voltage lower than the specified limit in both half cycles of AC.

569bcb72f484a4e969cdb0e60cfa1597

ed2c7bd83ec9f5c8261fe985b8c13143

The popularity of SLKOR diode products in Sacco Microelectronics is extremely high, among which Schottky diode and zener diode are particularly prominent, and the market demand is still increasing gradually. Shenzhen Saco Micro Semiconductor Co., Ltd. is a high-tech enterprise engaged in IC design, production and sales. Safeway's "SLKOR" brand and technology originated from South Korea. After several years' unremitting efforts by Mr. Song Shiqiang, the general manager, and Sakewei's team, it has already realized the localization of key links such as IP design, wafer flow, packaging and testing, sales service, etc. of component products, and has become an out-and-out "China Core", striving to break through the "bottleneck" situation of our chips in Europe and America. The main products of Samicro Semiconductor are MOS FET, hall Hall element, IGBT single transistor, SiC silicon carbide device, high-speed optocoupler, ESD static protection diode, TVS transient suppression diode, Schottky diode, COOLMOS, power management IC, etc. Since 2010, SAKO Micro has developed and produced the third generation semiconductor silicon carbide SiC components. Its applications include new energy vehicles, new energy power generation, high-power switching power supply and UPS uninterruptible power supply, etc. "SLKOR" brand common power device MOS tube and other products are widely used in lithium battery protection board, sweeping robot, TWS Bluetooth headset, electronic cigarette, outdoor lighting, PCBA board factory and other industries.

Prev:: 11 common PLL chip interface questions answers

Next:: SIC-MOSFET chip technology development

What are the differences: rectifier diode, Zina diode, and Schottky diode?

Advisory Service