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Vishay General Semiconductor - Diodes Division 1N6278AHE3/51
- Part No.:
- 1N6278AHE3/51
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-201AA, DO-27, Axial
- Datasheet:
-
1N6278AHE3/51.pdf
- Description:
- TVS DIODE 17.1VWM 27.7VC 1.5KE
- Quantity:
- Payment:
- Shipping:
Inventory:6,491
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Product details
Overview
1N6278AHE3/51 from Vishay General Semiconductor is a uni-directional Transient Voltage Suppressor (TVS) diode designed for primary overvoltage protection of sensitive electronics. It features a 19.0 V to 21.0 V breakdown voltage (VBR) at 1.0 mA test current, 17.1 V maximum stand-off voltage (VWM), 27.7 V clamping voltage (VC) at 54.2 A peak pulse current, and 1500 W peak pulse power rating with 10/1000 µs waveform - used in DC power rail and signal line protection for automotive ECUs and industrial sensor interfaces.
For engineers reviewing the 1N6278AHE3/51 datasheet, 1N6278AHE3/51 pinout, 1N6278AHE3/51 application, or 1N6278AHE3/51 equivalent, this part delivers AEC-Q101 qualified surge immunity, low incremental clamping resistance, fast sub-nanosecond response, and RoHS-compliant matte tin-plated leads suitable for J-STD-002 soldering.
Technical Context
The 1N6278AHE3/51 operates as a uni-directional avalanche diode, leveraging glass-passivated junction technology to achieve stable reverse breakdown and low leakage (<1.0 µA at VWM). Its clamping behavior follows a well-defined incremental voltage curve (ΔVC = VC − VBR) under 10/1000 µs transients, with thermal resistance of 15.4 °C/W (junction-to-lead) enabling reliable operation up to 175 °C junction temperature.
Designed for single-pulse transient suppression, it supports non-repetitive surge currents up to 200 A (8.3 ms half-sine) and exhibits a +0.090 %/°C temperature coefficient of VBR, ensuring predictable voltage drift across operating range. The device is rated for 6.5 W steady-state power dissipation on infinite heatsink at TL = 75 °C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBR (min/max) | 19.0 V / 21.0 V at 1.0 mA - defines precise avalanche initiation threshold for consistent overvoltage triggering |
| VWM | 17.1 V - maximum continuous reverse working voltage before leakage exceeds 1.0 µA |
| VC at IPPM | 27.7 V at 54.2 A - clamped voltage during 1500 W transient, limiting downstream stress |
| PPPM | 1500 W - peak pulse power handling per 10/1000 µs waveform, critical for lightning/ESD immunity |
| IFSM | 200 A - surge current rating for 8.3 ms half-sine, supporting high-energy inductive switch-off events |
| TJ max. | +175 °C - extended junction temperature rating enables under-hood automotive use |
| Qualification | AEC-Q101 qualified - validated for automotive-grade reliability and lifetime performance |
Pinout & Package
Package: Case Style 1.5KE - axial-leaded, molded epoxy body meeting UL 94 V-0 flammability rating; leads are matte tin plated, solderable per J-STD-002 and JESD 22-B102, with cathode indicated by color band.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction path | Connects to lower-potential side of protected circuit; conducts during forward surge or bias conditions |
| Cathode (banded end) | Avalanche clamping node | Reverse-biased terminal that initiates controlled breakdown when VRM exceeds VWM, shunting surge to ground |
Key Features
| Feature | Design Value |
|---|---|
| Glass passivated junction | Enables stable, repeatable avalanche characteristics and long-term parameter retention under thermal cycling |
| 1500 W peak pulse power (10/1000 µs) | Provides robust protection against ISO 7637-2 Pulse 1/2a/5a and IEC 61000-4-5 Level 4 surges |
| AEC-Q101 qualification | Validates suitability for automotive powertrain, body control, and ADAS modules requiring zero-failure reliability |
| Low clamping ratio (VC/VBR ≈ 1.4) | Minimizes overvoltage overshoot during clamping, reducing risk of MOSFET gate oxide damage |
| Sub-nanosecond response time | Clamps transients before IC internal protection circuits activate, preserving system-level ESD resilience |
Applications
| Automotive Power Supply Protection | Industrial Sensor Signal Line Protection |
|---|---|
Use Scenario: Protecting 12 V battery-fed microcontroller power rails in engine control units exposed to load dump and alternator ripple. IC Role / Device Role: Primary clamping element placed between VIN and GND, absorbing >100 V transients before they reach LDOs or MCU VDD. Use Value: Limits voltage to ≤27.7 V during 54.2 A surge, preventing brownout reset or permanent latch-up in 3.3 V/5 V logic domains. | Use Scenario: Shielding analog output lines (e.g., 4–20 mA current loop) of pressure sensors in factory automation PLCs. IC Role / Device Role: Uni-directional TVS connected anode-to-signal, cathode-to-VCC, suppressing positive-going transients induced by relay switching. Use Value: Maintains signal integrity below 17.1 V stand-off while clamping spikes to 27.7 V, avoiding ADC saturation or op-amp rail-to-rail clipping. |
| DC Motor Drive Board Protection | Telecom Power Interface Protection |
Use Scenario: Safeguarding H-bridge gate drivers and freewheeling diodes in brushed DC motor controllers subjected to back-EMF spikes. IC Role / Device Role: Mounted across motor terminals or supply rails to clamp inductive kickback energy. Use Value: Dissipates 1500 W pulses without degradation, enabling compact board layout without external snubbers or varistors. | Use Scenario: Front-end protection of PoE-powered network switches against lightning-induced surges on Ethernet data lines and auxiliary DC inputs. IC Role / Device Role: Used in conjunction with common-mode chokes and gas discharge tubes to form multi-stage protection network. Use Value: Provides fast, low-capacitance clamping (typical CJ < 100 pF at 0 V) without distorting 100BASE-TX signal integrity. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ20A | Lower PPPM (600 W), smaller SMB package (surface-mount), VBR = 22.2–24.5 V | Not AEC-Q101 qualified; suited for space-constrained consumer PCBs rather than automotive under-hood environments | Select when board area is limited and surge energy requirements are ≤600 W |
| 1.5KE20AHE3_A | Same electrical specs and AEC-Q101 qualification; identical VBR, VWM, VC, and PPPM; differs only in packaging (tape-and-reel vs. bulk) | No functional difference; both meet same mechanical and reliability standards per Vishay Doc. 88301 | Choose based on procurement logistics - 1.5KE20AHE3_A is preferred for automated SMT assembly |
Compared with SMBJ20A and 1.5KE20AHE3_A, the 1N6278AHE3/51 offers identical core protection performance but is supplied in axial-leaded bulk format optimized for through-hole prototyping and manual repair, while maintaining full AEC-Q101 compliance and 1500 W capability unmatched by surface-mount alternatives in its voltage class.
Availability
1N6278AHE3/51 is available at Aetrix Electronics and suitable for automotive ECU design, industrial sensor interface development, and DC motor controller production requiring stable component supply, long-lifecycle support, and AEC-Q101 traceability.
Supply support for 1N6278AHE3/51 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Vishay General Semiconductor is a global leader in discrete semiconductors, specializing in diodes, rectifiers, and protection devices with emphasis on reliability, efficiency, and application-specific optimization.
The 1N6278AHE3/51 belongs to Vishay's TRANSZORB® family of TVS diodes, engineered specifically for high-energy transient suppression in harsh environments including automotive, industrial, and telecom infrastructure.
FAQ
What is the breakdown voltage tolerance for the 1N6278AHE3/51?
The 1N6278AHE3/51 has a specified breakdown voltage range of 19.0 V to 21.0 V at 1.0 mA test current, representing ±5.3% tolerance around the nominal 20 V rating. This tight VBR window ensures consistent clamping onset across production lots and supports precise overvoltage margining in safety-critical designs like automotive power supplies where deviation could compromise system-level fault coverage.
Is the 1N6278AHE3/51 suitable for bi-directional transient protection?
No, the 1N6278AHE3/51 is a uni-directional TVS diode, intended for DC circuits where polarity is fixed. Its cathode band must be oriented toward the higher-potential rail. For bi-directional AC or floating signal line protection, Vishay specifies CA-suffix variants such as 1N6278CAHE3/51 - which is not interchangeable with the 1N6278AHE3/51 due to different internal structure and clamping symmetry.
Does the 1N6278AHE3/51 require a heatsink for standard operation?
No external heatsink is required for transient suppression duty, as the 1N6278AHE3/51 handles 1500 W pulses for ≤1 ms without thermal runaway. However, for continuous power dissipation above 6.5 W (e.g., sustained leakage or frequent surges), thermal design must account for RθJL = 15.4 °C/W and RθJA = 75 °C/W. In most automotive and industrial applications, PCB copper pour under the leads provides sufficient heat spreading without added heatsinking.
How does the 1N6278AHE3/51 compare to MOV-based protection?
The 1N6278AHE3/51 offers faster response (<1 ns vs. ~20–50 ns for MOVs), no wear-out mechanism, and tighter voltage clamping (27.7 V vs. typical MOV VC ≥35 V at same current). Unlike MOVs, it exhibits no capacitance shift with aging or repeated surges, making it preferable for precision analog and high-speed digital interfaces where signal integrity and long-term stability are critical - especially in AEC-Q101-compliant automotive systems.
What is the lead finish and soldering compatibility of the 1N6278AHE3/51?
The 1N6278AHE3/51 features matte tin-plated leads compliant with J-STD-002 and JESD 22-B102, supporting reflow and wave soldering processes. It passes JESD 201 Class 2 whisker testing (HE3 suffix), and is rated for solder dip at 275 °C for up to 10 seconds. These attributes ensure robust intermetallic formation and long-term solder joint reliability in high-vibration environments like automotive chassis-mounted electronics.
1N6278AHE3/51 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Package/Case:
- DO-201AA, DO-27, Axial
- Series:
- TransZorb®
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 17.1V
- Voltage - Breakdown (Min):
- 19V
- Voltage - Clamping (Max) @ Ipp:
- 27.7V
- Current - Peak Pulse (10/1000µs):
- 54.2A
- Power - Peak Pulse:
- 1500W (1.5kW)
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 1.5KE
1N6278AHE3/51 FAQ
1.How can I place an order for 1N6278AHE3/51 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N6278AHE3/51 on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for 1N6278AHE3/51 reliable?
The price and inventory of 1N6278AHE3/51 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N6278AHE3/51 is usually 5 days.
3.What payment methods are accepted for 1N6278AHE3/51?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N6278AHE3/51 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N6278AHE3/51?
1N6278AHE3/51 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N6278AHE3/51 order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for 1N6278AHE3/51?
For technical support, including 1N6278AHE3/51 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N6278AHE3/51 requirements.
6.How does Aetrix verify that 1N6278AHE3/51 is sourced from the original manufacturer or authorized distributors?
All 1N6278AHE3/51 products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that 1N6278AHE3/51 meets industry standards.
7.What is the process for return or replacement of 1N6278AHE3/51?
All 1N6278AHE3/51 units undergo pre-shipment inspection (PSI). If there is an issue with 1N6278AHE3/51, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The 1N6278AHE3/51 part is unused and in its original packaging.
Return procedure for 1N6278AHE3/51:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N6278AHE3/51 Tags
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