My Inquiry
My Account
Vishay General Semiconductor - Diodes Division SMBJ78AHM3/H
- Part No.:
- SMBJ78AHM3/H
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ78AHM3/H.pdf
- Description:
- TVS DIODE 78VWM 126VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:3,606
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMBJ78AHM3/H from Vishay General Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in SMB (DO-214AA) package, designed for clamping voltage transients on power and signal lines. It features 78 V stand-off voltage (VWM), 86.7–95.8 V breakdown voltage (VBR) at 1 mA, 126 V maximum clamping voltage (VC) at 4.8 A peak pulse current (IPPM), and 600 W peak pulse power (10/1000 µs waveform). It protects MOSFETs, ICs, and sensor interfaces in industrial power supplies and telecom line cards.
For engineers reviewing the SMBJ78AHM3/H datasheet, SMBJ78AHM3/H pinout, SMBJ78AHM3/H application, or SMBJ78AHM3/H equivalent, this page delivers verified electrical specs, thermal derating behavior, AEC-Q101 qualification status, halogen-free RoHS compliance (HM3 suffix), and real-world clamping performance under repetitive surge conditions.
Technical Context
This TVS diode operates as a unidirectional avalanche clamp, with cathode-banded polarity and fast response time (<1 ns) to transient overvoltages. Its glass-passivated junction ensures stable breakdown characteristics and low incremental surge resistance (≈26 Ω, derived from ΔVC/ΔIPPM = (126 V − 78 V)/4.8 A).
Thermal design relies on RθJA = 100 °C/W (on 0.2" × 0.2" copper pads) and RθJL = 20 °C/W, enabling operation up to +150 °C junction temperature. The HM3 suffix confirms halogen-free, RoHS-compliant construction and AEC-Q101 qualification per JESD22-B102 whisker testing and MSL Level 1 reflow profile (260 °C peak).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 78 V - Maximum continuous reverse operating voltage before significant leakage; defines safe working margin below clamping threshold. |
| VBR (min/max) | 86.7 V / 95.8 V at IT = 1 mA - Confirmed breakdown range ensuring reliable turn-on during transients without premature conduction. |
| VC @ IPPM | 126 V at 4.8 A - Clamped voltage seen by protected circuit during 10/1000 µs surge; determines downstream component voltage stress. |
| PPPM | 600 W - Peak pulse power handling capability under standard 10/1000 µs waveform; supports IEC 61000-4-5 Level 3/4 surge immunity. |
| ID @ VWM | 1.0 µA - Reverse leakage at rated stand-off voltage; negligible power loss and minimal impact on high-impedance sensor bias networks. |
| TJ max. | +150 °C - Maximum junction temperature rating; enables use in under-hood automotive modules and enclosed industrial enclosures. |
| Package | SMB (DO-214AA) - Standardized surface-mount outline (5.21 mm × 4.06 mm × 2.20 mm) compatible with automated pick-and-place and reflow soldering. |
Pinout & Package
Package: SMB (DO-214AA), molded plastic case with matte tin-plated leads, UL 94 V-0 rated compound, cathode indicated by band.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward current entry / transient return path | Connected to ground or low-impedance return plane; completes clamping loop during positive-going surges on cathode-side lines. |
| Cathode | Protected line connection | Connected to the line being protected (e.g., 78 V rail or signal trace); avalanche conduction occurs when voltage exceeds VBR relative to anode. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive-grade reliability including temperature cycling, HTRB, and ESD robustness-enables use in ADAS power rails and body control modules. |
| Halogen-free & RoHS-compliant (HM3) | Meets IEC 61249-2-21 and JEDEC J-STD-020; eliminates brominated flame retardants while maintaining UL 94 V-0 flammability rating. |
| 600 W peak pulse power (10/1000 µs) | Withstands repeated 1 kV/500 A surges per IEC 61000-4-5; suitable for front-end protection of AC/DC converters and PoE injectors. |
| Low clamping ratio (VC/VBR ≈ 1.33) | Indicates high surge current efficiency and minimal voltage overshoot-critical for protecting 100 V-rated MOSFETs and gate drivers. |
| MSL Level 1 moisture sensitivity | Allows unlimited floor life and standard reflow without baking; reduces manufacturing overhead in high-volume SMT lines. |
Applications
| Industrial Motor Drives | Telecom Power Feeds |
|---|---|
|
Use Scenario: Protection of IGBT gate driver supply rails against switching-induced transients in variable-frequency drives. IC Role / Device Role / Timing Role: Unidirectional TVS placed between 78 V auxiliary supply and ground to clamp inductive kickback spikes. Use Value: Limits voltage excursion to ≤126 V, preventing gate oxide rupture in 100 V-rated isolated gate drivers without adding series impedance. |
Use Scenario: Surge suppression on -48 V DC power feeds in central office line cards exposed to lightning-induced surges. IC Role / Device Role / Timing Role: Cathode tied to -48 V rail, anode to chassis ground; clamps negative transients exceeding 78 V magnitude. Use Value: Maintains <1 µA leakage at nominal voltage, avoiding load regulation error while delivering 600 W transient dissipation per event. |
| Automotive Body Control Modules | Industrial Sensor Signal Conditioning |
|
Use Scenario: Input protection for LIN bus transceivers powered from switched 12 V, subject to load dump and ISO 7637-2 pulses. IC Role / Device Role / Timing Role: Mounted at connector interface to shunt transients before reaching transceiver VCC pin. Use Value: AEC-Q101 qualification ensures survival across -40 °C to +125 °C ambient with no parameter shift after 1000 surge cycles. |
Use Scenario: Overvoltage safeguard on analog output lines (e.g., 4–20 mA transmitter outputs) connected to PLC analog inputs. IC Role / Device Role / Timing Role: Cathode on signal line, anode grounded; clamps ESD events and cable coupling transients. Use Value: 126 V clamping voltage preserves integrity of 24 V system-level isolation barriers while adding <0.1 pF junction capacitance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ78AHE3/H | Same VWM, VBR, VC, and PPPM; RoHS-compliant but not halogen-free (E3 vs HM3); lacks AEC-Q101 qualification. | Approved for commercial/industrial use only; unsuitable for automotive under-hood environments requiring AEC-Q101. | Select when halogen-free content is not mandated and automotive qualification is unnecessary. |
| SAC78 | Same 78 V VWM and 600 W rating, but in SMC (DO-214AB) package (larger footprint, higher IFSM = 200 A); slightly higher VC (128 V). | Better suited for high-energy surge paths (e.g., AC mains input) where PCB space allows larger package and higher surge current is needed. | Choose when board layout permits SMC footprint and surge current margin >4.8 A is required. |
Compared with SMBJ78AHM3/H, SMBJ78AHE3/H omits halogen-free and automotive qualification but offers identical electrical protection; SAC78 trades compact SMB size for higher surge endurance in a larger package-making SMBJ78AHM3/H optimal for space-constrained, automotive-grade, halogen-free designs.
Availability
SMBJ78AHM3/H is available at Aetrix Electronics and suitable for industrial motor drives, telecom power feeds, automotive body control modules, and industrial sensor signal conditioning requiring stable component supply and long-term lifecycle support.
Supply support for SMBJ78AHM3/H 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, power efficiency, and AEC-Q qualification.
The SMBJ series targets high-reliability transient suppression in automotive, industrial, and telecom infrastructure, with design focus on low clamping ratio, repeatable surge endurance, and process-controlled avalanche junctions.
FAQ
What is the maximum clamping voltage of SMBJ78AHM3/H at its rated peak pulse current?
The SMBJ78AHM3/H has a maximum clamping voltage (VC) of 126 V at its specified peak pulse current (IPPM) of 4.8 A under a 10/1000 µs waveform. This value is measured per ANSI/IEEE C62.35 and reflects worst-case voltage seen by downstream components during standardized surge events. The SMBJ78AHM3/H maintains this clamping performance across its full operating temperature range of -55 °C to +150 °C.
Is SMBJ78AHM3/H suitable for automotive applications?
Yes, SMBJ78AHM3/H is AEC-Q101 qualified, confirming its suitability for automotive applications including body control modules, infotainment power supplies, and ADAS subsystems. The HM3 suffix denotes halogen-free, RoHS-compliant construction validated for temperature cycling, high-temperature reverse bias, and mechanical shock. Its 150 °C maximum junction temperature supports under-hood deployment when mounted per recommended pad layout.
How does the HM3 suffix differ from E3 or HE3 in the SMBJ78A family?
The HM3 suffix on SMBJ78AHM3/H indicates halogen-free, RoHS-compliant, and AEC-Q101 qualified construction. In contrast, E3 denotes RoHS-compliant but non-halogen-free commercial grade, and HE3 adds AEC-Q101 qualification without halogen-free content. Only HM3 meets all three criteria-making SMBJ78AHM3/H the sole choice when halogen-free content and automotive qualification are both required.
What is the reverse leakage current of SMBJ78AHM3/H at its stand-off voltage?
The SMBJ78AHM3/H exhibits a maximum reverse leakage current (ID) of 1.0 µA at its rated stand-off voltage (VWM) of 78 V and TA = 25 °C. This ultra-low leakage ensures minimal power loss in always-on systems and avoids loading effects on high-impedance sensor bias networks or precision reference circuits. Leakage remains below 5 µA up to 125 °C ambient per thermal derating curves.
Can SMBJ78AHM3/H be used in bidirectional transient protection?
No, SMBJ78AHM3/H is a unidirectional TVS diode, identifiable by its cathode band marking. For bidirectional protection, Vishay specifies the CA-suffix variant (e.g., SMBJ78CA). Using SMBJ78AHM3/H in bidirectional configurations risks forward conduction during negative transients, potentially damaging the device or failing to protect the circuit. Always match polarity: cathode to protected line, anode to ground for unidirectional operation.
SMBJ78AHM3/H Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Package/Case:
- DO-214AA, SMB
- Series:
- TransZorb®
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Discontinued at Digi-Key
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 78V
- Voltage - Breakdown (Min):
- 86.7V
- Voltage - Clamping (Max) @ Ipp:
- 126V
- Current - Peak Pulse (10/1000µs):
- 4.8A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- Telecom
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AA (SMB)
SMBJ78AHM3/H FAQ
1.How can I place an order for SMBJ78AHM3/H through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ78AHM3/H 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 SMBJ78AHM3/H reliable?
The price and inventory of SMBJ78AHM3/H are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ78AHM3/H is usually 5 days.
3.What payment methods are accepted for SMBJ78AHM3/H?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ78AHM3/H transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ78AHM3/H?
SMBJ78AHM3/H orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ78AHM3/H 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 SMBJ78AHM3/H?
For technical support, including SMBJ78AHM3/H datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ78AHM3/H requirements.
6.How does Aetrix verify that SMBJ78AHM3/H is sourced from the original manufacturer or authorized distributors?
All SMBJ78AHM3/H 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 SMBJ78AHM3/H meets industry standards.
7.What is the process for return or replacement of SMBJ78AHM3/H?
All SMBJ78AHM3/H units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ78AHM3/H, 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 SMBJ78AHM3/H part is unused and in its original packaging.
Return procedure for SMBJ78AHM3/H:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ78AHM3/H Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
-
D5V0L1B2WS-7
Diodes Incorporated
Tech Hub
Comparator circuit design covering voltage thresholds, input limits, open-collector outputs, LM393 wiring, op-amp differences, hysteresis, timing, window detection and practical fault diagnosis.
Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
