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Taiwan Semiconductor Corporation 1KSMB18AH
- Part No.:
- 1KSMB18AH
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
1KSMB18AH.pdf
- Description:
- TVS DIODE 15.3VWM 25.5VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:4,543
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Product details
Overview
1KSMB18AH from Taiwan Semiconductor is a unidirectional 1000W surface-mount Transient Voltage Suppressor (TVS) diode in DO-214AA (SMB) package, with breakdown voltage 17.1–18.9 V, stand-off voltage 15.3 V, clamping voltage 25.5 V at 39.2 A, and AEC-Q101 qualification for automotive-grade surge protection.
For engineers reviewing the 1KSMB18AH datasheet, 1KSMB18AH pinout, 1KSMB18AH application, or 1KSMB18AH equivalent, key selection criteria include unidirectional polarity, 10/1000 µs waveform capability, ISO 7637-2 Pulse 1/2a/2b/3a/3b compliance, moisture sensitivity level 1, and junction temperature range of –55°C to +175°C.
Technical Context
The 1KSMB18AH operates as a unidirectional avalanche diode designed for fast clamping of high-energy transients on DC power rails and signal lines. Its glass-passivated junction ensures stable breakdown behavior, while sub-1 ps response time enables protection against ESD and electrical fast transients before sensitive downstream circuitry is damaged.
It delivers 1000 W peak pulse power under standardized 10/1000 µs waveform conditions, with thermal resistance RθJL = 20 °C/W and RθJA = 100 °C/W. The device supports steady-state power dissipation up to 5 W and forward surge current up to 100 A (8.3 ms half-sine), making it suitable for inductive load switching and automotive subsystem protection.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBR min/max | 17.1 V / 18.9 V - defines minimum and maximum voltage at which avalanche conduction begins reliably at 1 mA test current |
| VWM | 15.3 V - maximum continuous reverse operating voltage before leakage exceeds 1 µA; sets safe DC bias margin |
| VC@IPP | 25.5 V at 39.2 A - clamped voltage during 10/1000 µs transient; determines protected circuit's maximum stress level |
| PPPSM | 1000 W - peak pulse power handling per single non-repetitive event; defines transient energy absorption capacity |
| TJ max | +175 °C - maximum junction temperature; enables operation in under-hood automotive environments |
| IFSM | 100 A - peak forward surge current rating; supports protection of circuits exposed to inductive kickback |
Pinout & Package
Package: DO-214AA (SMB), surface-mount, cathode-banded unidirectional configuration. Matte tin-plated leads, UL 94V-0 molding compound, 0.110 g typical weight.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side reference terminal | Connected to ground or low-potential node; completes conduction path during reverse transient |
| Cathode | High-side transient input terminal | Connected to protected line (e.g., 12 V rail); blocks normal operation but conducts during overvoltage |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive electronics use including engine control, body modules, and infotainment systems |
| Glass passivated junction | Ensures long-term stability of breakdown voltage and low parameter drift across temperature and life cycles |
| Response time < 1.0 ps | Enables clamping before ESD or EFT pulses propagate into IC inputs, reducing risk of latch-up or gate oxide damage |
| ISO 7637-2 compliant | Meets automotive standard for load dump, supply interruption, and coupled transient immunity (Pulse 1/2a/2b/3a/3b) |
| Moisture sensitivity level 1 | Allows unlimited floor life before reflow; eliminates baking requirement and simplifies SMT manufacturing |
Applications
| Automotive Power Rail Protection | LED Driver Input Protection |
|---|---|
Use Scenario: Protecting 12 V battery-fed ECUs from load dump and alternator transients. IC Role / Device Role / Timing Role: Unidirectional TVS placed between power input and ground to clamp surges above 15.3 V. Use Value: Limits voltage seen by downstream LDOs and microcontrollers to ≤25.5 V during 1000 W transients, preventing permanent damage. | Use Scenario: Safeguarding constant-current LED drivers from inductive switching spikes in automotive lighting. IC Role / Device Role / Timing Role: Parallel-connected TVS absorbing flyback energy from driver FET turn-off. Use Value: Clamps transient peaks within 1 ps, preserving driver IC integrity and avoiding false shutdown or thermal runaway. |
| Industrial Sensor Interface Protection | USB Port ESD Suppression |
Use Scenario: Shielding 4–20 mA loop-powered sensors from field-induced surges in factory automation. IC Role / Device Role / Timing Role: Series-connected TVS on sensor supply line to suppress common-mode transients. Use Value: Maintains 15.3 V stand-off while delivering 25.5 V clamping, ensuring analog front-end ICs operate within absolute maximum ratings. | Use Scenario: Adding secondary-level ESD protection on VBUS line of USB 2.0 host ports in embedded devices. IC Role / Device Role / Timing Role: Standoff-rated TVS placed upstream of USB power switch to absorb contact ESD events. Use Value: Withstands >15 kV HBM per AEC-Q101, limiting VBUS overshoot to 25.5 V without affecting 5 V regulation stability. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ18A | Same DO-214AA package, identical VBR (17.1–18.9 V), but lower PPPSM = 600 W and higher VC = 29.2 V | Less robust for ISO 7637-2 Pulse 1 (load dump); not AEC-Q101 qualified | Select when cost sensitivity outweighs automotive qualification and 1000 W surge margin |
| 1.5KE18A | Through-hole DO-15 package, same VBR, PPPSM = 1500 W, but slower response (>1 ns) and no AEC-Q101 or ISO 7637-2 validation | Requires PCB redesign; unsuitable for automated SMT or automotive vibration environments | Choose only for legacy through-hole designs where board space and assembly method permit |
Compared with SMBJ18A and 1.5KE18A, the 1KSMB18AH provides superior automotive readiness via AEC-Q101 and ISO 7637-2 compliance, tighter thermal resistance (RθJL = 20 °C/W), and optimized SMT manufacturability-making it the preferred choice for new automotive and industrial surface-mount designs requiring validated 1000 W transient immunity.
Availability
1KSMB18AH is available at Aetrix Electronics and suitable for automotive power rail protection, LED driver input protection, industrial sensor interface protection, and USB port ESD suppression requiring stable component supply and full traceability.
Supply support for 1KSMB18AH 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, rectifiers, and MOSFETs, with global distribution and AEC-Q101 certification capabilities.
The 1KSMB series is engineered specifically for high-reliability automotive and industrial transient suppression, emphasizing robustness under ISO 7637-2 pulses, low clamping voltage, and zero reflow sensitivity (MSL Level 1).
FAQ
What is the polarity configuration of the 1KSMB18AH?
The 1KSMB18AH is a unidirectional TVS diode, with cathode marked by a band on the DO-214AA package. It conducts only during reverse overvoltage events and blocks forward current like a standard rectifier. This configuration is confirmed in the "Devices for Bipolar Applications" note specifying CAH suffix for bidirectional variants-absent in 1KSMB18AH.
Does the 1KSMB18AH meet automotive qualification standards?
Yes, the 1KSMB18AH is AEC-Q101 qualified and explicitly validated for ISO 7637-2 Pulse 1, 2a, 2b, 3a, and 3b transient immunity. These qualifications are stated in the FEATURES section and supported by thermal and electrical test data across –55°C to +175°C junction temperature range.
What is the maximum clamping voltage of the 1KSMB18AH and at what current?
The 1KSMB18AH has a maximum clamping voltage VC of 25.5 V at peak impulse current IPP = 39.2 A under 10/1000 µs waveform conditions. This value is specified in the ELECTRICAL SPECIFICATIONS table and defines the upper voltage limit imposed on protected circuitry during worst-case transient events.
Can the 1KSMB18AH be used in bidirectional applications?
No-the 1KSMB18AH is unidirectional only. Bidirectional operation requires the CAH-suffixed variant (e.g., 1KSMB18CAH), which uses dual-die construction. The datasheet explicitly states "For Bidirectional use CAH suffix", confirming that 1KSMB18AH lacks symmetrical breakdown capability and must not be substituted in AC or bipolar signal paths.
What is the moisture sensitivity level (MSL) and reflow profile compatibility of the 1KSMB18AH?
The 1KSMB18AH has MSL Level 1 per J-STD-020, meaning it may be stored indefinitely at ambient conditions without baking prior to reflow. Its matte tin-plated leads comply with J-STD-002 solderability requirements, supporting standard lead-free reflow profiles up to 260°C peak temperature without degradation.
1KSMB18AH Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-214AA, SMB
- Series:
- 1KSMB
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 15.3V
- Voltage - Breakdown (Min):
- 17.1V
- Voltage - Clamping (Max) @ Ipp:
- 25.5V
- Current - Peak Pulse (10/1000µs):
- 39.2A
- Power - Peak Pulse:
- 1000W (1kW)
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AA (SMB)
1KSMB18AH FAQ
1.How can I place an order for 1KSMB18AH through Aetrix?
Please submit a Request for Quotation (RFQ) for 1KSMB18AH 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 1KSMB18AH reliable?
The price and inventory of 1KSMB18AH are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1KSMB18AH is usually 5 days.
3.What payment methods are accepted for 1KSMB18AH?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1KSMB18AH transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1KSMB18AH?
1KSMB18AH orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1KSMB18AH 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 1KSMB18AH?
For technical support, including 1KSMB18AH datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1KSMB18AH requirements.
6.How does Aetrix verify that 1KSMB18AH is sourced from the original manufacturer or authorized distributors?
All 1KSMB18AH 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 1KSMB18AH meets industry standards.
7.What is the process for return or replacement of 1KSMB18AH?
All 1KSMB18AH units undergo pre-shipment inspection (PSI). If there is an issue with 1KSMB18AH, 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 1KSMB18AH part is unused and in its original packaging.
Return procedure for 1KSMB18AH:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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