Can TVS tube and voltage regulator diode replace each other?

TVS diode (transient voltage suppression diode) is a new product developed on the basis of voltage regulator technology. It is one of the new high-efficiency circuit protection devices, with a response time of P seconds and high wave absorption ability.

Zener diode (also known as Zener diode) is a diode developed to maintain voltage stability within a large range of current changes by utilizing the reverse breakdown state of the pn junction.

From the definitions of the two, it can be seen that their commonalities are mainly reflected in:

1) Within a certain range, the voltage at both ends can be limited;

2) The long-term operation endurance value is almost the same and is related to the volume power consumption;

Regarding the differences between TVS diodes and voltage regulators:

1. Working principle

TVS diode: Avalanche effect, its working impedance can immediately decrease to a very low conduction value during high-energy instantaneous overvoltage pulses, allowing maximum current to pass through and clamping the voltage to a predetermined level, thereby avoiding damage to precision components in the circuit.

Zener diode: Zener tunneling effect, when the reverse voltage reaches and exceeds the stable voltage, the reverse current suddenly increases while the voltage across the diode remains constant.

2. Classification

TVS diode: can be divided into unipolar and bipolar according to polarity; According to their purpose, they can be divided into universal and specialized types.

Voltage regulator: According to the voltage regulation level, it can be divided into low-voltage diodes (less than 40V) and high-voltage voltage regulator diodes (greater than 200V); According to the material, it can be divided into N-type and P-type.

3. Main parameters

TVS diode: reverse breakdown voltage (VBR), reverse leakage current (IR), maximum reverse operating voltage (VRMM), maximum clamping voltage (VC), capacitance value (CJ), maximum peak pulse current (IPP), reverse pulse peak power (PPR), etc.

Voltage regulator: Stable voltage (VZ), stable current (IE), dynamic resistance (RZ), maximum dissipated power (PZM), maximum/minimum stable operating current (IZmax/IZmin), temperature coefficient (AT), etc.

4. Purpose

TVS diode: used for transient voltage protection; In terms of voltage accuracy, TVS diodes are within a certain range; In terms of flow capacity, TVS diodes can reach several hundred amperes; In terms of voltage regulation, TVS diodes have a voltage range of 6.8V-550V.

Voltage regulator: clamp protection for the drain and source; In terms of voltage accuracy, voltage regulators are relatively precise; In terms of current carrying capacity, the surge current resistance of the voltage regulator is very small; In terms of voltage regulation, the voltage regulator ranges from 3.3V to 75V.

After such a clear comparison, it is found that in many cases, TVS diodes and voltage regulators cannot be replaced by each other, each with its own advantages and disadvantages.