TVS - Diodes

Part Number	Description / PDF	Quantity
SMAJ85CA-TR STMicroelectronics	TVS DIODE 85V 178V SMA	7541
SM15T6V8A STMicroelectronics	TVS DIODE 5.8V 13.4V SMC	0
SMBJ6.0CA-TR STMicroelectronics	TVS DIODE 6V 13.7V SMB	11050
SM4T14CAY STMicroelectronics	TVS DIODE 12V 25.3V SMA	0
ESDALC6-4N4 STMicroelectronics	TVS DIODE 3V 10V 4UQFN	0
SMC30J33A STMicroelectronics	TVS DIODE 33V 53.3V SMC	2500
SMA6T15AY STMicroelectronics	TVS DIODE 12.8V 27.2V SMA	0
SMA4F22AY STMicroelectronics	AUTOMOTIVE POWER-RAIL TVS PROTEC	10000
SMBJ5.0A-TR STMicroelectronics	TVS DIODE 5V 13.4V SMB	8981
SMC30J5.0A STMicroelectronics	TVS DIODE 5V 9.2V SMC	6615
SM6T30A STMicroelectronics	TVS DIODE 25.6V 53.5V SMB	700
SMBJ26A-TR STMicroelectronics	TVS DIODE 26V 53.5V SMB	531
LDP01-35AY STMicroelectronics	TVS DIODE 30V 45.5V D2PAK	1949
STIEC45-26AS STMicroelectronics	TVS DIODE 26V 45V SMC	171
SMA6F18A STMicroelectronics	600 W TVS IN SMA FLAT	9673
SMA6J48A-TR STMicroelectronics	TVS DIODE 48V 88.4V SMA	5055
SM4T47CAY STMicroelectronics	TVS DIODE 40V 84V SMA	3825
SMC30J5.0CA STMicroelectronics	TVS DIODE 5V 9.2V SMC	2279
SMB6F100AY STMicroelectronics	AUTOMOTIVE 600 W, 100 V TVS IN S	9990
SM6T75AY STMicroelectronics	TVS DIODE 64.1V 134V SMB	2489

TVS - Diodes

1. Overview

Transient Voltage Suppression (TVS) Diodes are semiconductor devices designed to protect sensitive electronics from voltage spikes caused by ESD (electrostatic discharge), lightning, or switching events. By clamping transient voltages to safe levels, TVS diodes ensure circuit reliability in modern electronic systems. Their fast response time (<1ps) and low clamping voltage make them critical components in high-speed data lines, power supplies, and automotive electronics.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Unidirectional TVS	Single-polarity protection, asymmetrical voltage response	DC power lines, automotive systems
Bidirectional TVS	Symmetrical protection for AC signals	Telecom interfaces (e.g., RJ45), USB 3.0	Multichannel TVS	Multiple protection paths in single package	HDMI ports, DisplayPort interfaces	Automotive TVS	AEC-Q101 qualified, high surge capability	ECU modules, CAN bus protection

3. Structure and Composition

TVS diodes utilize a PN junction semiconductor structure with optimized doping profiles. Key components include:

Silicon epitaxial layer for precise voltage control
Passivation layer (SiO2/Nitride) to reduce leakage current
Backside metallization for low-inductance packaging
DO-214, SOD-123, or WCSP packaging variants

4. Key Technical Specifications

Parameter	Description	Importance
Breakdown Voltage (Vbr)	Minimum voltage where TVS activates	Determines protection threshold
Clamping Voltage (Vc)	Max voltage during transient event	Must be below protected IC's max rating
Peak Pulse Current (Ipp)	Maximum surge current handling	Defines robustness against large transients
Response Time (tresp)	Time to switch from off to on state	Crucial for ESD protection (typically <1ps)
Leakage Current (Ir)	Off-state current at working voltage	Impacts power efficiency

5. Application Areas

Major industries and typical equipment:

Telecommunications: 5G base stations, optical transceivers
Automotive: CAN/LIN bus protection, ADAS sensors
Industrial: PLCs, motor drives
Consumer Electronics: USB Type-C interfaces, Wi-Fi modules
Renewable Energy: Solar inverters, wind turbine controllers

6. Leading Manufacturers and Products

Manufacturer	Product Series	Key Features
Littelfuse	SP301x Series	USB 3.1 Gen2 protection, 0.35pF capacitance
ON Semiconductor	NUP41060	6-channel ESD protection, 30kV HBM
STMicroelectronics	ESDA8401	Automotive-grade, 150A surge rating
Infineon	ESD320	Single-line protection, 0.25pF for HDMI 2.1

7. Selection Guidelines

Key considerations:

Operating voltage must be below Vbr (typically 1.1 Voper)
Clamping voltage should stay under protected IC's maximum ratings
Packaging selection based on board space and thermal requirements
Environmental factors: temperature range, humidity resistance
Compliance with standards (IEC 61000-4-2, ISO 10605)

Example: For a 12V automotive circuit, select a bidirectional TVS with Vbr=15V, Vc<30V, and Ipp>50A to handle load dump events.

8. Industry Trends

Key development directions:

Miniaturization: 0201 package (0.6 0.3mm) for mobile devices
Integration: Combo devices with filters and shielding
Higher robustness: 40kV+ ESD protection for industrial IoT
Advanced materials: Silicon carbide (SiC) for high-temperature applications
AI-driven selection tools for optimized component matching