SZESD7421N2T5G

TVS - Diodes and SZESD7421N2T5G Application Field and Working Principle

TVS (Transient Voltage Suppressors) are unidirectional diodes specifically designed to protect electronic components from overvoltage transients generated by electrical processes such as inductive load switching, PNP / NPN transistor switches, lightning strikes, and electrostatic discharge (ESD). They are generally used to suppress runaway through-currents (also known as surge currents).

The SZESD7421N2T5G is a 7-pin TVS diode component developed by Diodes Incorporated with an operating range of 5.5V – 21V. This diode is designed as a low capacitance device that provides superior performance in ESD and electrical transient (IEC 61000-4-2 & 61000-4-4) protection applications. Its compact size also makes it suitable for portable devices and small form-factor applications.

The SZESD7421N2T5G can handle a maximum peak pulse power of 1.5kW (t=8/20μsec), which is approximately three times the peak power of standard thyrectors. It features a low voltage drop of 0.4V@A and a fast reset time of 20ns. With an operating temperature range of –55C to +125C, this diode is suitable for a wide range of applications in the automotive, telecom, consumer electronics and industrial markets.

The working principle of the SZESD7421N2T5G is based on the Zener breakdown effect. When the applied voltage is increased beyond a critical value, current starts flowing in the reverse direction, resulting in a breakdown of the diode junction. This breakdown causes the diode to “clamp” the voltage to a level where it will not cause any damage to the components being protected.

In addition to its protection functions, the SZESD7421N2T5G has the ability to suppress high-frequency noise generated due to electromagnetic interference or radio-frequency interference. This is achieved by its fast switching time, which is capable of cutting off transient noise within 20ns. This makes it ideal for communications and automotive applications in which noise suppression is critical.

The SZESD7421N2T5G is also designed for power switching applications, such as protecting power modules and power supply systems. Its fast reset time and low voltage drop make it suitable for pulsed loads and high voltage / current applications. Its reverse clamping action ensures that the transient protection circuitry can handle the high peak power of a surge. The device’s wide operating temperature range allows it to be used in harsh and extreme industrial environments.

The SZESD7421N2T5G has successfully passed IEC 61000-4-2 (air discharge) and IEC 61000-4-4 (contact discharge) standards tests and is developed using semiconductor processes that are compliant with RoHS and other environmental regulations. It is widely used in applications that require ESD and surge protection, such as battery systems, communications systems, automotive electronics, power supply systems and industrial equipment.