My Inquiry
My Account
Taiwan Semiconductor Corporation 1KSMB18A
.jpg)
- Part No.:
- 1KSMB18A
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
1KSMB18A.pdf
- Description:
- TVS DIODE 15.3VWM 25.5VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:4,798
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
1KSMB18A from Taiwan Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in DO-214AA (SMB) package, rated for 1000W peak pulse power, 17.1–18.9V breakdown voltage at 1mA, and 25.5V maximum clamping voltage at 39.2A peak current. It protects DC power rails in switching mode power supplies and consumer displays against ESD and surge transients per ISO 7637-2.
For engineers reviewing the 1KSMB18A datasheet, 1KSMB18A pinout, 1KSMB18A application, or 1KSMB18A equivalent, key selection criteria include unidirectional polarity, 15.3V stand-off voltage, <1.0µA reverse leakage at VWM, 1.0ps response time, and compliance with J-STD-020 moisture sensitivity level 1.
Technical Context
The 1KSMB18A operates as a silicon avalanche diode with glass-passivated junction, delivering fast transient suppression via controlled avalanche breakdown. Its unidirectional configuration enables protection of positive-rail DC systems without bidirectional conduction paths.
It meets ISO 7637-2 Pulse 1/2a/2b/3a/3b automotive transient immunity requirements and supports automated SMT placement. Thermal performance includes RθJL = 20°C/W and RθJA = 100°C/W, enabling reliable operation up to TJ = 175°C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBR min/max | 17.1 V / 18.9 V at IT = 1 mA - defines minimum and maximum guaranteed avalanche onset voltage under standard test conditions |
| VWM | 15.3 V - maximum continuous reverse operating voltage before significant leakage begins |
| IPP | 39.2 A - peak impulse current supported with 10/1000 µs waveform, directly determining surge energy handling |
| VC@IPP | 25.5 V - clamped voltage during full-rated surge, defining worst-case overvoltage seen by protected circuitry |
| PPPSM | 1000 W - non-repetitive peak pulse power rating, critical for transient energy absorption capability |
| TJ max | 175 °C - maximum junction temperature, setting thermal derating limits for high-ambient designs |
| Moisture Sensitivity | Level 1 per J-STD-020 - allows unlimited floor life and standard reflow without baking preconditioning |
Pinout & Package
Package: DO-214AA (SMB), surface-mount, single-die unidirectional TVS diode with cathode band marking. 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 return path; forms current path during reverse-biased clamping |
| Cathode | High-side transient input terminal | Connected to protected line (e.g., +12V rail); avalanche conduction occurs when voltage exceeds VBR |
Key Features
| Feature | Design Value |
|---|---|
| Glass-passivated junction | Ensures stable, repeatable breakdown characteristics and long-term reliability under repeated surge stress |
| Response time <1.0 ps | Enables effective suppression of ultrafast ESD events before downstream ICs experience overstress |
| ISO 7637-2 compliance | Validates suitability for automotive power-line transient protection including load dump and inductive switching pulses |
| RoHS & halogen-free | Meets IEC 61249-2-21 and global environmental directives for industrial and consumer end equipment |
| Automated placement compatibility | DO-214AA outline and lead finish support high-yield, high-speed pick-and-place assembly |
Applications
| Switching Mode Power Supply (SMPS) | AC/DC Adapters |
|---|---|
Use Scenario: Input rectifier output rail protection against line surges and MOSFET switching transients. IC Role / Device Role / Timing Role: Unidirectional TVS clamps positive-going transients on the high-side DC bus. Use Value: Limits voltage excursion to ≤25.5 V during 1000 W surges, preventing damage to PWM controllers and bulk capacitors. | Use Scenario: Secondary-side DC output protection in wall-mounted adapters subject to user-induced ESD and cable coupling. IC Role / Device Role / Timing Role: Standoff-rated TVS absorbs fast transients before they reach USB or barrel-jack output connectors. Use Value: 15.3 V VWM ensures no conduction during normal 12 V or 15 V output operation while clamping >25 V spikes. |
| Television Power Boards | Monitor Backlight Drivers |
Use Scenario: Protection of main 24 V or 48 V power distribution net against inrush and relay bounce transients. IC Role / Device Role / Timing Role: Primary-side TVS placed upstream of DC-DC converters and PFC stages. Use Value: 1000 W rating handles repetitive switching noise and infrequent lightning-induced surges without degradation. | Use Scenario: Surge suppression on CCFL or LED driver enable/control lines exposed to board-level ESD. IC Role / Device Role / Timing Role: Low-leakage (≤1.0 µA) TVS maintains signal integrity while guarding against human-body-model discharges. Use Value: 1.0 ps response ensures clamping activation prior to logic-level IC latch-up thresholds being exceeded. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ18A (Bourns) | Same DO-214AA package, identical 17.1–18.9 V VBR, but VC = 27.7 V (vs. 25.5 V for 1KSMB18A) | Higher clamping voltage reduces protection margin for sensitive 24 V logic interfaces | Select 1KSMB18A where tighter clamping is required; SMBJ18A offers broader distributor availability |
| P6SMB18A (ON Semiconductor) | Identical electrical specs and DO-214AA footprint; VC = 25.5 V, IPP = 39.2 A, same 1000 W rating | No functional difference; validated for same ISO 7637-2 pulse profiles | P6SMB18A is a direct form-fit-function alternative with equivalent performance and qualification history |
Compared with SMBJ18A and P6SMB18A, the 1KSMB18A provides identical surge rating and lower clamping voltage than SMBJ18A, while matching P6SMB18A's exact clamping and leakage performance-making it optimal for space-constrained 24 V systems requiring minimal overvoltage headroom.
Availability
1KSMB18A is available at Aetrix Electronics and suitable for switching mode power supplies, AC/DC adapters, and television power boards requiring stable component supply with consistent parametric performance across production lots.
Supply support for 1KSMB18A 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, and power devices since 1979.
The 1KSMB series was developed specifically for high-energy, surface-mount transient suppression in automotive and industrial power systems, emphasizing robustness, AEC-Q200 readiness, and automated assembly compatibility.
FAQ
What is the polarity configuration of the 1KSMB18A?
The 1KSMB18A is a unidirectional TVS diode, configured with anode and cathode terminals marked by a cathode band on the DO-214AA package body. It conducts only during reverse-bias overvoltage events and blocks forward current like a standard rectifier diode. This polarity must be observed during PCB layout to ensure correct protection orientation on positive-rail lines.
Does the 1KSMB18A meet automotive transient standards?
Yes, the 1KSMB18A meets ISO 7637-2 Pulse 1, 2a, 2b, 3a, and 3b requirements for 12 V automotive electrical systems. Its 1000 W peak pulse rating, fast <1.0 ps response, and specified clamping behavior under standardized waveforms validate its use in front-end protection for ECUs, infotainment power modules, and body control units.
What is the maximum clamping voltage of the 1KSMB18A at rated surge current?
The maximum clamping voltage (VC) of the 1KSMB18A is 25.5 V when subjected to its rated 39.2 A peak impulse current with a 10/1000 µs waveform. This value is guaranteed across the full operating temperature range and defines the upper voltage limit imposed on protected circuitry during worst-case surge events.
Is the 1KSMB18A RoHS and halogen-free compliant?
Yes, the 1KSMB18A is RoHS compliant and halogen-free per IEC 61249-2-21. The molding compound contains no brominated flame retardants or chlorine-based additives, and all metallization and plating meet EU Directive 2011/65/EU requirements for restricted substances in electronic components.
What is the moisture sensitivity level (MSL) rating for the 1KSMB18A?
The 1KSMB18A has a moisture sensitivity level (MSL) of Level 1 per J-STD-020, meaning it may be stored indefinitely at ambient conditions (<30°C / 60% RH) without baking prior to reflow soldering. This eliminates floor-life constraints and simplifies SMT manufacturing flow for high-volume production.
1KSMB18A 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:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AA (SMB)
1KSMB18A FAQ
1.How can I place an order for 1KSMB18A through Aetrix?
Please submit a Request for Quotation (RFQ) for 1KSMB18A 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 1KSMB18A reliable?
The price and inventory of 1KSMB18A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1KSMB18A is usually 5 days.
3.What payment methods are accepted for 1KSMB18A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1KSMB18A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1KSMB18A?
1KSMB18A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1KSMB18A 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 1KSMB18A?
For technical support, including 1KSMB18A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1KSMB18A requirements.
6.How does Aetrix verify that 1KSMB18A is sourced from the original manufacturer or authorized distributors?
All 1KSMB18A 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 1KSMB18A meets industry standards.
7.What is the process for return or replacement of 1KSMB18A?
All 1KSMB18A units undergo pre-shipment inspection (PSI). If there is an issue with 1KSMB18A, 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 1KSMB18A part is unused and in its original packaging.
Return procedure for 1KSMB18A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1KSMB18A 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
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 …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
