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Taiwan Semiconductor Corporation SMBJ51CAH
- Part No.:
- SMBJ51CAH
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ51CAH.pdf
- Description:
- TVS DIODE 51VWM 82.4VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:4,967
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Product details
Overview
SMBJ51CAH from Taiwan Semiconductor is a bidirectional transient voltage suppressor (TVS) diode in DO-214AA (SMB) package, designed for high-energy ESD and surge protection in automotive and industrial power rails. It features a 51 V working stand-off voltage (VWM), 56.7–62.7 V breakdown voltage (VBR), 82.4 V maximum clamping voltage (VC) at 7.6 A peak impulse current (IPP), and 600 W peak pulse power rating with <1.0 ps response time.
For engineers reviewing the SMBJ51CAH datasheet, SMBJ51CAH pinout, SMBJ51CAH application, or SMBJ51CAH equivalent, key selection criteria include bidirectional clamping capability, AEC-Q101 qualification, ISO 7637-2 Pulse 1/2a/2b/3a/3b compliance, low leakage (<1 µA at 51 V), and DO-214AA mechanical compatibility with automated SMT assembly.
Technical Context
The SMBJ51CAH operates as a bidirectional avalanche diode, symmetrically clamping transients above ±56.7 V in either polarity while maintaining ≤1 µA blocking leakage below 51 V. Its glass-passivated junction ensures stable VBR tolerance and long-term reliability under repetitive surge stress.
Thermal performance is defined by RθJC = 10 °C/W and RθJA = 55 °C/W, enabling sustained operation up to TJ = +150 °C. It meets JESD201 Class 2 whisker resistance and J-STD-020 Moisture Sensitivity Level 1 - suitable for reflow without baking.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 51 V - Maximum continuous DC or RMS voltage the device blocks without conduction |
| VBR min / max | 56.7 V / 62.7 V - Breakdown occurs within this range at 1 mA test current; defines turn-on threshold symmetry |
| VC @ IPP | 82.4 V @ 7.6 A - Clamped voltage during 10/1000 µs surge; limits downstream IC stress to safe level |
| PPK | 600 W - Peak non-repetitive surge power handling per IEC 61000-4-5 and ISO 7637-2 |
| IR @ VWM | <1 µA - Negligible standby leakage, critical for low-power sensor and battery-backed circuits |
| Response time | <1.0 ps - Sub-nanosecond avalanche initiation enables protection of high-speed interfaces and microcontrollers |
Pinout & Package
DO-214AA (SMB) surface-mount package: molded epoxy case rated UL 94V-0, matte tin-plated leads, cathode band marking for unidirectional variants only - SMBJ51CAH has no polarity marking due to bidirectional symmetry.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode/Cathode (symmetrical) | Bidirectional avalanche junction | Either terminal serves as anode or cathode depending on transient polarity; no fixed orientation required in PCB layout |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive underhood and powertrain applications per stress test requirements |
| ISO 7637-2 compliance | Withstands Pulse 1 (inductive load dump), Pulse 2a/2b (switching transients), and Pulse 3a/3b (capacitive coupling) without degradation |
| Glass passivated junction | Enhances long-term stability of VBR and leakage under thermal cycling and humidity exposure |
| Moisture sensitivity level 1 | Zero bake requirement before reflow; compatible with standard SMT assembly lines |
| Halogen-free & RoHS compliant | Meets IEC 61249-2-21 and EU RoHS Directive 2011/65/EU for green manufacturing |
Applications
| Automotive Power Rail Protection | Industrial Sensor Interface Protection |
|---|---|
Use Scenario: 12 V/24 V vehicle battery line exposed to load dump and alternator transients. IC Role / Device Role / Timing Role: Bidirectional clamping element placed upstream of DC-DC converters and MCU power inputs. Use Value: Limits transient overvoltage to ≤82.4 V during ISO 7637-2 Pulse 5a (load dump), preventing damage to 3.3 V/5 V logic supplies. |
Use Scenario: RS-485 or CAN bus nodes connected to long cables in factory automation systems. IC Role / Device Role / Timing Role: Primary surge shunt at connector entry point, protecting transceiver ESD structures. Use Value: Sub-1 ps response ensures clamping initiates before transceiver internal junctions break down during EFT bursts. |
| LED Driver Input Protection | Smart Meter AC/DC Power Supply Protection |
Use Scenario: Constant-current LED driver input subjected to inductive switching spikes from relay-controlled loads. IC Role / Device Role / Timing Role: Parallel-connected TVS across bulk capacitor input to absorb 600 W surges. Use Value: 600 W PPK rating handles repetitive 10/1000 µs transients common in commercial lighting control panels. |
Use Scenario: Mains-connected smart meter power supply encountering lightning-induced surges on AC input. IC Role / Device Role / Timing Role: First-stage clamping device between bridge rectifier and primary-side controller. Use Value: 51 V VWM allows reliable blocking of 36 V peak rectified voltage while clamping >1 kV transients to safe levels. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| Littelfuse SMAJ51CA | Same DO-214AC (SMA) package; 51 V VWM, 87.1 V VC @ 7.0 A; slightly higher clamping voltage and lower IPP | Lower power density (400 W vs. 600 W); less suitable for high-energy ISO 7637-2 Pulse 5a | Select when footprint constraints require SMA instead of SMB, and surge energy is limited to ≤400 W |
| ON Semiconductor 1.5SMC51CA | DO-214AB (SMC) package; 51 V VWM, 85.5 V VC @ 7.3 A; 1500 W PPK rating but larger footprint | Higher surge capacity but incompatible with SMB land pattern; requires PCB redesign | Choose for systems needing >600 W headroom where board space permits SMC package |
Compared with SMAJ51CA and 1.5SMC51CA, SMBJ51CAH delivers optimal balance of 600 W surge handling, DO-214AA compactness, AEC-Q101 qualification, and bidirectional symmetry - making it preferred for space-constrained automotive and industrial modules requiring certified robustness without layout change.
Availability
SMBJ51CAH is available at Aetrix Electronics and suitable for automotive infotainment power rails, industrial PLC I/O protection, and smart lighting driver designs requiring stable component supply across multi-year production cycles.
Supply support for SMBJ51CAH 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
Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, specializing in TVS diodes, rectifiers, MOSFETs, and power management devices.
The SMBJH series was developed specifically for AEC-Q101-compliant automotive and harsh-environment industrial applications demanding high-reliability transient suppression with zero derating up to +150 °C junction temperature.
FAQ
What does the 'CAH' suffix indicate in SMBJ51CAH?
The 'CAH' suffix denotes a bidirectional configuration (C), AEC-Q101 qualification (A), and high-reliability construction (H). Unlike unidirectional 'H' variants, SMBJ51CAH provides symmetrical clamping in both polarities - essential for protecting AC-coupled or floating signal lines and dual-rail power domains without polarity concerns.
Is SMBJ51CAH compatible with lead-free reflow soldering processes?
Yes, SMBJ51CAH is fully compatible with standard lead-free reflow profiles (JEDEC J-STD-020 Level 1), thanks to its moisture sensitivity level 1 rating and matte tin-plated terminals. No pre-bake is required, and it withstands peak temperatures up to 260 °C for 30 seconds without parametric shift or delamination.
How does SMBJ51CAH differ from SMBJ51AH?
SMBJ51AH is unidirectional with a cathode band marking and forward voltage drop (~3.5 V), while SMBJ51CAH is bidirectional with no polarity marking and symmetrical avalanche behavior in both directions. SMBJ51CAH replaces two unidirectional devices in differential or AC applications, reducing BOM count and PCB area.
Can SMBJ51CAH be used in place of a unidirectional TVS in a DC power rail?
Yes - SMBJ51CAH functions identically to a unidirectional device when used on a single-polarity rail (e.g., +12 V), clamping positive transients to ground and negative transients to the rail. Its bidirectional design adds margin against reverse-bias faults and eliminates orientation errors during placement.
What standards does SMBJ51CAH meet for automotive ESD immunity?
SMBJ51CAH meets ISO 7637-2 Pulse 1 (inductive load dump), Pulse 2a/2b (switching transients), and Pulse 3a/3b (capacitive coupling), and supports system-level ESD testing per ISO 10605. Its <1.0 ps response time ensures protection against fast-rising EFT bursts that bypass slower suppressors.
SMBJ51CAH Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-214AA, SMB
- Series:
- SMBJH
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 51V
- Voltage - Breakdown (Min):
- 56.7V
- Voltage - Clamping (Max) @ Ipp:
- 82.4V
- Current - Peak Pulse (10/1000µs):
- 7.6A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AA (SMB)
SMBJ51CAH FAQ
1.How can I place an order for SMBJ51CAH through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ51CAH 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 SMBJ51CAH reliable?
The price and inventory of SMBJ51CAH are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ51CAH is usually 5 days.
3.What payment methods are accepted for SMBJ51CAH?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ51CAH transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ51CAH?
SMBJ51CAH orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ51CAH 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 SMBJ51CAH?
For technical support, including SMBJ51CAH datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ51CAH requirements.
6.How does Aetrix verify that SMBJ51CAH is sourced from the original manufacturer or authorized distributors?
All SMBJ51CAH 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 SMBJ51CAH meets industry standards.
7.What is the process for return or replacement of SMBJ51CAH?
All SMBJ51CAH units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ51CAH, 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 SMBJ51CAH part is unused and in its original packaging.
Return procedure for SMBJ51CAH:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ51CAH Tags
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