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Taiwan Semiconductor Corporation SMBJ40AH
- Part No.:
- SMBJ40AH
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ40AH.pdf
- Description:
- TVS DIODE 40VWM 64.5VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:5,155
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Product details
Overview
SMBJ40AH from Taiwan Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode in DO-214AA (SMB) package, designed for automotive-grade ESD and surge protection. It features a 40 V working stand-off voltage (VWM), 44.4–49.1 V breakdown voltage (VBR), 64.5 V maximum clamping voltage (VC) at 9.7 A peak pulse current (IPP), and 600 W peak pulse power (PPK) with <1.0 ps response time - deployed in automotive lighting control modules and powertrain sensor interfaces.
For engineers reviewing the SMBJ40AH datasheet, SMBJ40AH pinout, SMBJ40AH application, or SMBJ40AH equivalent, key selection criteria include clamping performance under ISO 7637-2 Pulse 1/2a/2b/3a/3b, AEC-Q101 qualification status, unidirectional polarity marking, thermal resistance (RθJA = 55 °C/W), and compatibility with automated SMT placement on high-reliability PCBs.
Technical Context
The SMBJ40AH operates as a unidirectional avalanche diode, leveraging glass-passivated junction technology to achieve fast transient suppression (<1.0 ps response) and low leakage (<1 µA at 40 V). Its clamping behavior follows IEEE C62.35 standards for 10/1000 µs waveform surges, with guaranteed VC ≤ 64.5 V at IPP = 9.7 A.
Thermally, it supports continuous operation up to TJ = 150 °C and derates linearly above TA = 25 °C per Fig. 2. The device meets JESD201 Class 2 whisker resistance and J-STD-020 Moisture Sensitivity Level 1, enabling reflow compatibility without preconditioning.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 40 V - Maximum continuous reverse operating voltage before conduction begins; defines system-level standoff margin in 36 V automotive supply rails. |
| VBR min/max | 44.4 V / 49.1 V @ IT = 1 mA - Confirmed avalanche onset range; ensures reliable triggering above nominal bus voltage with margin against tolerance drift. |
| VC @ IPP | 64.5 V @ 9.7 A - Measured clamping voltage during 10/1000 µs surge; limits downstream IC stress to safe levels per ISO 7637-2 compliance. |
| PPK | 600 W - Peak non-repetitive pulse power rating; supports single-event transients like load dump or inductive kick without failure. |
| ID @ VWM | <1 µA - Reverse leakage at rated stand-off; minimizes quiescent power loss and avoids false triggering in low-power sensor circuits. |
| RθJA | 55 °C/W - Junction-to-ambient thermal resistance; enables thermal design for 3 W steady-state dissipation in standard FR-4 layouts with 1 oz copper. |
Pinout & Package
Package: DO-214AA (SMB), surface-mount, cathode-banded unidirectional configuration. Matte tin-plated leads compliant with J-STD-002 solderability; weight ≈ 0.090 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side reference terminal | Connected to ground or low-impedance return path; forms current sink during transient clamping events. |
| Cathode | High-side protected node | Connected to protected line (e.g., CAN_H, LIN, sensor VCC); blocks forward current until VBR exceeded. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive underhood applications including temperature cycling, mechanical shock, and humidity testing per AEC specification. |
| Glass passivated junction | Enables stable VBR over lifetime and improved reliability vs. epoxy-passivated alternatives in high-humidity environments. |
| ISO 7637-2 compliance | Guaranteed clamping performance across Pulse 1 (inductive load disconnect), Pulse 2a/2b (battery interruption), and Pulse 3a/3b (switching noise). |
| Moisture sensitivity level 1 | Zero floor-life limitation; can be mounted directly from reel without baking, reducing manufacturing overhead and moisture-related popcorning risk. |
Applications
| Automotive Lighting Control | Powertrain Sensor Interface |
|---|---|
Use Scenario: Protecting LED driver ICs and microcontrollers from load-dump transients in headlamp and tail-light modules. IC Role / Device Role: Unidirectional TVS placed between 12 V supply rail and ground, clamping surges before they reach sensitive logic. Use Value: Limits clamped voltage to ≤64.5 V during 9.7 A 10/1000 µs pulses, preventing latch-up or gate oxide damage in 5 V/3.3 V controllers. |
Use Scenario: Shielding crankshaft/camshaft position sensors from inductive switching noise and battery reversal events. IC Role / Device Role: Standoff protection on sensor VCC line, absorbing ISO 7637-2 Pulse 1 energy without degrading signal integrity. Use Value: Maintains <1 µA leakage at 40 V, avoiding DC offset errors in precision analog front-ends while delivering 600 W surge immunity. |
| Body Control Module (BCM) | Infotainment Power Rail |
Use Scenario: Safeguarding LIN bus transceivers and window motor drivers from ESD and relay bounce in door modules. IC Role / Device Role: Localized TVS at each actuator interface, providing point-of-entry protection with minimal PCB area. Use Value: Leverages DO-214AA footprint for high-density layout; achieves <1.0 ps response to suppress fast EFT bursts per IEC 61000-4-4. |
Use Scenario: Guarding USB-C PD and display power supplies against hot-swap transients and cable coupling noise. IC Role / Device Role: Primary clamping device on 5 V/9 V/12 V input rails upstream of DC-DC converters. Use Value: Delivers 64.5 V clamping at 9.7 A with RθJA = 55 °C/W, enabling thermal stability in compact infotainment enclosures without heatsinking. |
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 SMAJ40A | Same DO-214AC (SMA) package; slightly higher VC = 64.8 V @ 9.7 A; RθJA = 65 °C/W vs. 55 °C/W. | Lower power density due to larger thermal resistance; requires wider copper pour for equivalent thermal performance. | Prefer SMBJ40AH where board space is constrained and thermal management is critical. |
| Vishay SMF40A | DO-219AB (SOD-123FL) package; lower PPK = 400 W; VC = 64.0 V @ 6.3 A; not AEC-Q101 qualified. | Limited to non-automotive industrial use; insufficient for ISO 7637-2 Pulse 1 load dump requirements. | Select SMBJ40AH for AEC-Q101-compliant automotive designs requiring full 600 W surge handling. |
Compared with SMAJ40A and SMF40A, the SMBJ40AH offers superior thermal performance (55 °C/W), AEC-Q101 qualification, and full ISO 7637-2 compliance - making it the preferred choice for automotive power rail protection where reliability and regulatory alignment are mandatory.
Availability
SMBJ40AH is available at Aetrix Electronics and suitable for automotive lighting control, powertrain sensor protection, and body control module designs requiring stable component supply, long-term lifecycle support, and traceable sourcing.
Supply support for SMBJ40AH 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 semiconductor manufacturer specializing in discrete power devices, TVS diodes, and rectifiers with global automotive and industrial certifications.
The SMBJH series was developed specifically for AEC-Q101-compliant transient suppression in 12 V/24 V automotive systems, emphasizing robust clamping, low leakage, and high-volume SMT manufacturability.
FAQ
What is the polarity configuration of SMBJ40AH?
The SMBJ40AH is a unidirectional TVS diode with cathode band marking indicating the high-side protected terminal. It conducts only during reverse-biased overvoltage events - forward voltage drop is 3.5 V at 50 A, consistent with SMBJ5.0H–SMBJ90H family specifications. This polarity enables precise placement on supply rails where ground-referenced clamping is required.
Does SMBJ40AH meet ISO 7637-2 Pulse 1 requirements?
Yes, SMBJ40AH is explicitly validated for ISO 7637-2 Pulse 1 (inductive load dump), Pulse 2a/2b (battery interruption), and Pulse 3a/3b (switching transients). Its 64.5 V clamping voltage at 9.7 A and 600 W peak power rating ensure compliance when used with appropriate PCB layout and trace inductance - confirmed in TSC's application notes for automotive power rail protection.
What is the maximum junction temperature rating for SMBJ40AH?
The SMBJ40AH has a maximum junction temperature (TJ) of +150 °C and operates across a storage temperature range of −55 °C to +150 °C. Its thermal performance is characterized by RθJC = 10 °C/W and RθJA = 55 °C/W, allowing sustained operation at full 3 W steady-state power dissipation in typical automotive ambient conditions with standard copper land patterns.
Is SMBJ40AH compatible with lead-free reflow soldering processes?
Yes, SMBJ40AH is RoHS compliant and halogen-free per IEC 61249-2-21. Its matte tin-plated leads meet J-STD-002 solderability requirements and support standard lead-free reflow profiles (peak 260 °C, 10 s max), with moisture sensitivity level 1 eliminating the need for pre-baking - verified per J-STD-020.
How does SMBJ40AH differ from SMBJ40H?
SMBJ40AH has tighter VBR tolerance (44.4–49.1 V) versus SMBJ40H (44.4–54.3 V), resulting in more predictable clamping onset and reduced variation in real-world surge response. Both share identical package (DO-214AA), PPK (600 W), and VC (64.5 V / 71.4 V respectively), but SMBJ40AH's narrower breakdown range improves design margin in safety-critical automotive applications.
SMBJ40AH 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:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 40V
- Voltage - Breakdown (Min):
- 44.4V
- Voltage - Clamping (Max) @ Ipp:
- 64.5V
- Current - Peak Pulse (10/1000µs):
- 9.7A
- 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)
SMBJ40AH FAQ
1.How can I place an order for SMBJ40AH through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ40AH 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 SMBJ40AH reliable?
The price and inventory of SMBJ40AH are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ40AH is usually 5 days.
3.What payment methods are accepted for SMBJ40AH?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ40AH transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ40AH?
SMBJ40AH orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ40AH 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 SMBJ40AH?
For technical support, including SMBJ40AH datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ40AH requirements.
6.How does Aetrix verify that SMBJ40AH is sourced from the original manufacturer or authorized distributors?
All SMBJ40AH 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 SMBJ40AH meets industry standards.
7.What is the process for return or replacement of SMBJ40AH?
All SMBJ40AH units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ40AH, 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 SMBJ40AH part is unused and in its original packaging.
Return procedure for SMBJ40AH:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ40AH Tags
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