The Vishay T15B12A to T15B51A series part number can be replaced by Leiditech.

The replacement part number list for the SMB packaging 1500W TVS series of products by Lei ditech is as follows：

1、Leiditech SMB Package Offers 1500W TVS Core Advantages

l The perfect combination of miniaturization and high power density

The traditional 1500W TVS diodes usually adopt the larger SMC (DO-214AB) package. However, the new generation of 1500W TVS from Shanghai Leiditech (Leiditech SMB15J series) uses a smaller SMB (DO-214AA) package, yet its peak pulse power still reaches 1500W. While saving up to 58% of PCB space, it provides the same level of surge protection capability, making it highly suitable for modern electronic devices with limited space, such as highly integrated automotive ECU (Electronic Control Unit) and compact power modules.

l Strong surge absorption capacity

The peak pulse power of 1500W (measured according to the 10/1000μs test waveform) indicates that it can absorb and dissipate a large amount of instantaneous overvoltage energy, such as load sudden drop, lightning-induced surge, and transient voltage caused by inductive loads (such as motors, relays) switching. It provides robust protection for the subsequent precision integrated circuits (ICs), power chips, sensors, etc., preventing system failure or hardware damage.

l Wide range of voltage options （5V-220V）

This series typically offers two types: unidirectional and bidirectional. It covers a breakdown voltage range from 5V to 220V. The unidirectional TVS is usually used in DC circuits to protect a single polarity voltage; the bidirectional TVS is suitable for AC circuits or DC lines that need to prevent positive and negative surges. The wide voltage range enables it to be flexibly applied in automotive bus systems with voltages ranging from 12V, 24V, 48V to higher levels.

2、The main application markets of the Leiditech SMB15J series

With these advantages, the 1500W SMB package TVS diode is highly suitable for the following fields：

l Automotive electronics

l Industrial Electronics

Industrial automation control systems (PLC, I/O modules) 

Motor drive and control; 

Power protection for communication base stations.

l Consumer Electronics

Power modules for high-end household appliances 

High-power chargers, adapters. 

In summary, the core advantage of the 1500W TVS diode in SMB package lies in "small size, large capacity" - within the extremely compact SMB package, it offers a surge absorption capacity of up to 1500W. These characteristics make it an ideal protection solution for dealing with the demanding space and environmental challenges in modern automotive electronics and industrial applications.

3. Safety Precautions for the Lebao SMB15J Series

l Selection considerations: Choosing the appropriate breakdown voltage (VBR) and clamping voltage (Vc) is crucial. It is necessary to ensure that they are in line with the operating voltage and the maximum allowable voltage of the protected circuit. The reverse turn-off voltage (Vrwm) of the TVS should be slightly higher than the normal operating voltage of the protected circuit, but not lower than the maximum operating voltage of the circuit. Otherwise, it may cause the TVS to conduct prematurely or result in excessive leakage current. When subjected to the maximum surge current, the voltage across the TVS (clamping voltage Vc) must be lower than the maximum safe voltage that the protected circuit or component can withstand.

l  Layout and Heat Dissipation: Although these series of devices have excellent performance on their own, when designing the PCB layout, a good heat dissipation path should still be considered to ensure that they can fully utilize their potential to absorb a large amount of transient energy.

Bidirectional protection requirement: If the circuit needs to handle reverse surges, then the bidirectional SMB15JxxCA series should be considered for selection.

4、SMB15J Series 1500W Specification Book

Leiditech Electronics is committed to becoming a leading brand in electromagnetic compatibility solutions and component supply, offering products such as ESD, TVS, TSS, GDT, MOV, MOSFET, Zener, and inductors. Leiditech has an experienced R&D team that can provide personalized customization services based on customer needs, offering the best solutions to customers.