My Inquiry
My Account
Vishay General Semiconductor - Diodes Division SMAJ12AHM3_A/H
- Part No.:
- SMAJ12AHM3_A/H
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ12AHM3_A/H.pdf
- Description:
- TVS DIODE 12VWM 19.9VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:3,881
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMAJ12AHM3_A/H from Vishay General Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode in SMA (DO-214AC) package, designed for clamping fast-rising voltage transients up to 19.9 V at 20.1 A peak pulse current (10/1000 μs), with 12 V stand-off voltage and 400 W peak pulse power rating - used to protect MOSFETs, ICs, and sensor signal lines in automotive and industrial power electronics.
For engineers reviewing the SMAJ12AHM3_A/H datasheet, SMAJ12AHM3_A/H pinout, SMAJ12AHM3_A/H application, or SMAJ12AHM3_A/H equivalent, this part delivers AEC-Q101-qualified surge protection with low incremental surge resistance, 150 °C max junction temperature, and halogen-free RoHS compliance - critical for ESD and load-switching transient immunity in compact PCB layouts.
Technical Context
This TVS diode operates as a clamping device in reverse-biased configuration, triggering when reverse voltage exceeds 13.3–14.7 V breakdown range (at 1 mA test current), limiting transient energy by diverting surge current to ground before downstream components experience overvoltage. Its glass-passivated junction ensures stable leakage (<1 μA at 12 V) and fast response time (<1 ns).
Thermal performance is defined by 120 °C/W junction-to-ambient thermal resistance on standard 0.2" × 0.2" copper pads, enabling reliable operation under repetitive 0.01% duty cycle surges. The unidirectional polarity (cathode band marked) supports DC-biased rail protection without forward conduction during normal operation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Stand-off Voltage (VWM) | 12 V - maximum continuous reverse operating voltage before clamping begins; sets safe margin below system rail voltage. |
| Breakdown Voltage (VBR) | 13.3–14.7 V at 1 mA - precise voltage threshold where avalanche conduction initiates; defines clamping onset accuracy. |
| Clamping Voltage (VC) | 19.9 V at 20.1 A (10/1000 μs) - peak voltage seen by protected circuit during worst-case surge; determines component survivability. |
| Peak Pulse Power (PPPM) | 400 W - maximum transient energy absorption capability per pulse; enables robust protection against IEC 61000-4-5 Level 3 surges. |
| Peak Pulse Current (IPPM) | 20.1 A - maximum surge current the device can safely shunt without degradation; validates design margin for 12 V systems. |
| Junction Temperature Range | −55 to +150 °C - operational envelope supporting under-hood automotive and industrial environments without derating. |
| Package | SMA (DO-214AC) - industry-standard surface-mount outline with 3.99 mm × 4.50 mm footprint and 2.29 mm height; compatible with automated placement. |
Pinout & Package
Package: SMA (DO-214AC), molded plastic case with matte tin-plated leads, MSL level 1 (260 °C reflow peak), halogen-free and RoHS-compliant (HM3 suffix). Polarity indicated by cathode band on unidirectional devices.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side connection point | Connected to ground or return path; completes clamping loop during transient events. |
| Cathode | High-side connection point | Connected to protected line (e.g., 12 V rail or signal trace); reverse-biased during normal operation. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive-grade reliability including temperature cycling, humidity testing, and surge endurance - required for under-hood ECUs. |
| 400 W peak pulse power (10/1000 μs) | Supports IEC 61000-4-5 4th edition surge immunity up to 1 kV open-circuit / 500 A short-circuit test levels. |
| Glass passivated junction | Ensures stable VBR tolerance (±5%) and low leakage (<1 μA at VWM) across temperature and lifetime. |
| Low profile SMA package | Enables high-density layout on space-constrained boards while maintaining thermal dissipation via 0.2" × 0.2" copper pads. |
| Halogen-free & RoHS-compliant (HM3) | Fulfills EU Directive 2011/65/EU and IPC-1752A material declarations for sustainable manufacturing. |
Applications
| Automotive Body Control Module | Industrial PLC Input Protection |
|---|---|
Use Scenario: Protecting 12 V CAN bus power rails and microcontroller I/O from load-dump transients and relay coil flyback. IC Role / Device Role / Timing Role: Unidirectional clamping TVS placed between VBAT and GND, triggered within <1 ns of overvoltage event. Use Value: Limits voltage to ≤19.9 V during 100 ms load-dump pulses, preventing damage to 3.3 V/5 V logic and CAN transceivers. |
Use Scenario: Shielding 24 V digital input channels from field-wiring induced surges in factory automation cabinets. IC Role / Device Role / Timing Role: Standoff-rated TVS connected across input optocoupler terminals to clamp transients before isolation barrier. Use Value: Absorbs 400 W surges without degradation, ensuring >100,000-cycle reliability in harsh electromagnetic environments. |
| Consumer Appliance Motor Drive | Telecom Power Supply Input |
Use Scenario: Safeguarding gate drivers and bootstrap circuits in BLDC motor inverters subjected to inductive switching spikes. IC Role / Device Role / Timing Role: Fast-response TVS placed at half-bridge high-side supply node to suppress dV/dt-induced shoot-through risks. Use Value: Clamps 12 V rail transients to 19.9 V within nanoseconds, preserving MOSFET gate oxide integrity and timing margins. |
Use Scenario: Front-end protection for AC/DC adapters handling lightning-induced surges on telecom infrastructure power feeds. IC Role / Device Role / Timing Role: Primary-stage TVS mounted directly at input connector to shunt common-mode surges before rectification. Use Value: Withstands 20.1 A peak current at 19.9 V clamping, meeting GR-1089-CORE Level 3 surge requirements for outdoor equipment. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ12AHE3_A/H | Same electrical specs but RoHS-compliant commercial grade (E3), not halogen-free; lacks AEC-Q101 qualification. | Approved for non-automotive industrial and consumer use only; unsuitable for automotive OEM designs requiring AEC-Q101. | Select SMAJ12AHM3_A/H when halogen-free content and automotive qualification are mandatory; choose HE3 variant for cost-sensitive commercial applications. |
| SMBJ12A-HM3 | Higher 600 W peak pulse power rating, same 12 V VWM, but SMB (DO-214AA) package - 25% larger footprint and higher RθJA (140 °C/W). | Better suited for higher-energy surges but requires PCB redesign; less optimal for space-constrained automotive modules. | Prefer SMAJ12AHM3_A/H for tight-layout 12 V systems needing AEC-Q101; select SMBJ12A-HM3 only when surge energy exceeds 400 W capability. |
Compared with SMAJ12AHE3_A/H, SMAJ12AHM3_A/H adds halogen-free construction and AEC-Q101 validation for automotive use; versus SMBJ12A-HM3, it trades lower power rating for smaller size and better thermal performance on standard pads - making SMAJ12AHM3_A/H optimal for space-limited, qualified automotive protection.
Availability
SMAJ12AHM3_A/H is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC inputs, and consumer appliance motor drives requiring stable component supply with full traceability and long-term lifecycle support.
Supply support for SMAJ12AHM3_A/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, MOSFETs, optoelectronics, and passive components with emphasis on reliability and application-specific performance.
The SMAJ series is engineered for high-reliability transient suppression in automotive, industrial, and telecom systems - delivering consistent clamping behavior and AEC-Q101 validation for mission-critical voltage rail protection.
FAQ
What is the clamping voltage of SMAJ12AHM3_A/H at its rated peak pulse current?
The clamping voltage (VC) of SMAJ12AHM3_A/H is 19.9 V at 20.1 A peak pulse current with a 10/1000 μs waveform. This value represents the maximum voltage imposed on the protected circuit during a standardized surge event and is measured under JEDEC-defined conditions. SMAJ12AHM3_A/H maintains this clamping performance across its full operating temperature range and after repeated surge exposures, ensuring predictable protection behavior in real-world applications.
Is SMAJ12AHM3_A/H suitable for automotive applications?
Yes, SMAJ12AHM3_A/H is AEC-Q101 qualified and specifically designed for automotive use, including under-hood environments. Its halogen-free construction (HM3 suffix), 150 °C maximum junction temperature, and validated surge endurance meet stringent OEM requirements. SMAJ12AHM3_A/H is commonly deployed in body control modules, infotainment power supplies, and ADAS sensor interfaces where reliability under thermal and electrical stress is critical.
How does the SMAJ12AHM3_A/H differ from the SMAJ12A-E3 variant?
SMAJ12AHM3_A/H differs from SMAJ12A-E3 in three key aspects: it uses halogen-free molding compound (HM3 vs. E3), carries AEC-Q101 qualification, and features enhanced whisker resistance per JESD 201 Class 2. SMAJ12AHM3_A/H is intended for automotive and high-reliability industrial use, whereas SMAJ12A-E3 serves general commercial applications. Both share identical electrical parameters and SMA package dimensions.
What is the thermal resistance of SMAJ12AHM3_A/H, and how does it affect PCB layout?
SMAJ12AHM3_A/H has a typical junction-to-ambient thermal resistance (RθJA) of 120 °C/W when mounted on 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pads per terminal. This value assumes standard FR-4 board thickness and no internal copper planes. To maintain safe junction temperatures during repetitive surges, designers must allocate adequate copper area and avoid excessive trace length between SMAJ12AHM3_A/H and ground. Reducing pad size increases RθJA and may require derating IPPM.
Does SMAJ12AHM3_A/H have polarity marking, and how is it identified?
Yes, SMAJ12AHM3_A/H is unidirectional and features a visible cathode band on the SMA (DO-214AC) package body - located near the cathode terminal. This band must be oriented toward the positive side of the protected line (e.g., 12 V rail), with the anode connected to ground. Incorrect orientation prevents proper clamping and may result in device failure during surge events. The marking is laser-etched and compliant with JEDEC standards for surface-mount diode polarity identification.
SMAJ12AHM3_A/H Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Package/Case:
- DO-214AC, SMA
- Series:
- TransZorb®
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 12V
- Voltage - Breakdown (Min):
- 13.3V
- Voltage - Clamping (Max) @ Ipp:
- 19.9V
- Current - Peak Pulse (10/1000µs):
- 20.1A
- Power - Peak Pulse:
- 400W
- 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-214AC (SMA)
SMAJ12AHM3_A/H FAQ
1.How can I place an order for SMAJ12AHM3_A/H through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ12AHM3_A/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 SMAJ12AHM3_A/H reliable?
The price and inventory of SMAJ12AHM3_A/H are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ12AHM3_A/H is usually 5 days.
3.What payment methods are accepted for SMAJ12AHM3_A/H?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ12AHM3_A/H transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ12AHM3_A/H?
SMAJ12AHM3_A/H orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ12AHM3_A/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 SMAJ12AHM3_A/H?
For technical support, including SMAJ12AHM3_A/H datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ12AHM3_A/H requirements.
6.How does Aetrix verify that SMAJ12AHM3_A/H is sourced from the original manufacturer or authorized distributors?
All SMAJ12AHM3_A/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 SMAJ12AHM3_A/H meets industry standards.
7.What is the process for return or replacement of SMAJ12AHM3_A/H?
All SMAJ12AHM3_A/H units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ12AHM3_A/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 SMAJ12AHM3_A/H part is unused and in its original packaging.
Return procedure for SMAJ12AHM3_A/H:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ12AHM3_A/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 …
