My Inquiry
My Account
Taiwan Semiconductor Corporation SMBJ28A
- Part No.:
- SMBJ28A
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ28A.pdf
- Description:
- TVS DIODE 28VWM 45.4VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:10,862
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMBJ28A from Taiwan Semiconductor is a unidirectional 600W surface-mount transient voltage suppressor (TVS) diode designed for robust ESD and surge protection in DC power rails and signal lines. It features a 28V working stand-off voltage (VWM), 31.1–34.4V breakdown voltage (VBR), 45.4V maximum clamping voltage (VC) at 13.8A peak pulse current, and DO-214AA (SMB) package - ideal for automotive power supply input protection.
For engineers reviewing the SMBJ28A datasheet, SMBJ28A pinout, SMBJ28A application, or SMBJ28A equivalent, key selection criteria include clamping performance under ISO 7637-2 Pulse 1/2a/2b/3a/3b, leakage current ≤1µA at 28V, and thermal resistance (RθJA = 55°C/W) for board-level reliability in industrial control modules.
Technical Context
The SMBJ28A operates as a unidirectional avalanche diode with glass-passivated junction, enabling sub-1ps response to transients and stable clamping during 10/1000µs surge events. Its 600W non-repetitive peak pulse power rating is defined per ANSI/IEEE C62.35 and derated above 25°C ambient using the published pulse derating curve.
Junction temperature range spans −55°C to +150°C, with thermal resistance values of RθJC = 10°C/W and RθJA = 55°C/W confirming suitability for high-density PCB layouts. Polarity is marked by cathode band; no internal series impedance or integrated filtering is present - it functions strictly as a shunt-clamping device.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 28 V - Maximum continuous reverse operating voltage before significant leakage; defines safe DC rail margin. |
| VBR min/max | 31.1 V / 34.4 V @ IT = 1 mA - Confirmed avalanche onset range; ensures predictable turn-on during overvoltage. |
| VC @ IPP | 45.4 V @ 13.8 A - Clamped voltage during 10/1000µs surge; limits downstream IC stress to <46 V. |
| ID @ VWM | ≤1 µA - Ultra-low leakage preserves battery life and avoids false triggering in low-power systems. |
| PPK | 600 W - Peak impulse power handling per single 10/1000µs waveform; meets ISO 7637-2 compliance. |
| TJ max | +150 °C - Enables operation in under-hood automotive or industrial enclosures without derating. |
| RθJA | 55 °C/W - Thermal resistance from junction to ambient; guides copper pour and airflow requirements. |
Pinout & Package
Package: DO-214AA (SMB), surface-mount, matte tin-plated leads, polarity indicated by cathode band. Case meets UL 94V-0 flammability rating and JESD 201 Class 2 whisker resistance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side reference terminal | Connected to system ground or return path; forms shunt path during transient. |
| Cathode | High-side connection terminal | Connected to protected line (e.g., 24V rail); clamps to anode when voltage exceeds VBR. |
Key Features
| Feature | Design Value |
|---|---|
| Glass-passivated junction | Ensures stable VBR tolerance and long-term reliability under thermal cycling and humidity exposure. |
| Sub-1 ps response time | Enables suppression of fast ESD events (IEC 61000-4-2) before sensitive logic or analog circuitry reacts. |
| ISO 7637-2 compliance | Validated for automotive load-dump and inductive-switching immunity (Pulse 1/2a/2b/3a/3b). |
| Moisture sensitivity level 1 | Eliminates bake requirement prior to reflow; supports standard SMT assembly without special handling. |
| Halogen-free & RoHS compliant | Meets IEC 61249-2-21 and EU directives for environmentally constrained industrial and automotive programs. |
Applications
| Automotive Power Input Protection | Industrial PLC I/O Protection |
|---|---|
Use Scenario: 24V battery-fed ECUs exposed to load dump and alternator ripple. IC Role / Device Role / Timing Role: Shunt-clamping TVS placed between power rail and chassis ground. Use Value: Limits transient voltage to ≤45.4V, protecting downstream DC-DC converters and microcontrollers rated for 36V absolute max. |
Use Scenario: Digital input channels on programmable logic controllers interfacing with 24V sensors. IC Role / Device Role / Timing Role: Unidirectional overvoltage clamp on field-side signal lines. Use Value: Blocks >30V surges while maintaining <1µA leakage at 24V, preserving signal integrity and reducing false triggers. |
| LED Driver Supply Rail Protection | Medical Equipment DC Power Entry |
Use Scenario: Constant-current LED drivers powered from 28V telecom supplies subject to lightning-induced surges. IC Role / Device Role / Timing Role: Primary surge suppression at DC input stage before bulk capacitor. Use Value: Absorbs 600W pulses without degradation, ensuring driver IC survival during 10/1000µs transients per IEC 61000-4-5. |
Use Scenario: Auxiliary 28V DC power entry in diagnostic imaging subsystems requiring low EMI and high reliability. IC Role / Device Role / Timing Role: Secondary overvoltage guard after primary filter stage. Use Value: Provides certified clamping with ≤1µA leakage, avoiding interference with precision analog front-ends and meeting IEC 60601-1 creepage/clearance constraints. |
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 SMAJ28A | Same DO-214AC (SMA) package; 45.4V VC @ 13.8A, but RθJA = 65°C/W vs. SMBJ28A's 55°C/W. | Lower thermal efficiency requires larger copper area; not drop-in due to smaller SMA footprint. | Select SMAJ28A only if board space is constrained and thermal margin allows higher junction rise. |
| ON Semiconductor SMCJ28A | DO-214AB (SMC) package; identical 28V VWM and 45.4V VC, but PPK = 1500W and IPP = 33.1A. | Higher surge capacity suits harsher environments (e.g., railway traction), but larger footprint increases layout cost. | Choose SMCJ28A where multi-pulse or repeated surge exposure is expected and PCB real estate permits SMC size. |
Compared with SMAJ28A, SMBJ28A offers better thermal dissipation in the same general SMB form factor; versus SMCJ28A, it trades peak surge capacity for compactness and lower profile - optimal for space-constrained 24V industrial modules needing ISO 7637-2 compliance.
Availability
SMBJ28A is available at Aetrix Electronics and suitable for automotive body control modules, industrial PLC I/O cards, LED lighting drivers, and medical auxiliary power supplies requiring stable component supply across extended production lifecycles.
Supply support for SMBJ28A 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 for industrial and automotive markets.
The SMBJ series was engineered specifically for high-reliability, surface-mount transient suppression in 12V–170V DC systems - emphasizing low clamping voltage, tight VBR tolerance, and AEC-Q200 readiness for under-hood use.
FAQ
What is the maximum clamping voltage of SMBJ28A under a 10/1000µs surge?
The SMBJ28A has a maximum clamping voltage (VC) of 45.4 V when subjected to its rated peak pulse current of 13.8 A with a 10/1000µs waveform. This value is guaranteed per the datasheet's electrical specifications table and reflects worst-case device behavior at TA = 25°C. The SMBJ28A maintains this clamping performance across its full operating temperature range, making it suitable for protecting 24V-rated ICs against ISO 7637-2 transients.
Is SMBJ28A unidirectional or bidirectional?
SMBJ28A is a unidirectional TVS diode, indicated by the absence of "C" or "CA" suffix and confirmed by its cathode-band marking and forward voltage specification. It conducts only during reverse overvoltage events and blocks forward current up to 3.5 V at 50 A (per SMBJ series note). Bidirectional variants like SMBJ28CA exist but are distinct part numbers - SMBJ28A must be used with correct polarity orientation on the PCB.
Does SMBJ28A meet automotive surge immunity standards?
Yes, SMBJ28A meets ISO 7637-2 Pulse 1, 2a, 2b, 3a, and 3b requirements for transient immunity in 12V and 24V automotive systems. Its 600W peak pulse power rating, 45.4V clamping voltage, and sub-1ps response time are validated for these waveforms. While not AEC-Q200 certified out-of-box, Taiwan Semiconductor qualifies SMBJ-series devices to AEC-Q200 stress test levels upon request - confirm qualification status with Aetrix for automotive production programs.
What is the leakage current of SMBJ28A at its working voltage?
At its 28 V working stand-off voltage (VWM), the SMBJ28A exhibits a maximum blocking leakage current (ID) of 1 µA at TA = 25°C. This ultra-low leakage remains stable across its full operating temperature range (−55°C to +150°C) and ensures minimal power loss in always-on systems such as battery-backed sensors or standby power rails. The SMBJ28A's leakage performance supports energy-sensitive designs without compromising surge protection capability.
What package type does SMBJ28A use, and what are its mounting requirements?
SMBJ28A uses the DO-214AA (SMB) surface-mount package, with matte tin-plated leads compatible with standard J-STD-002 soldering processes. Its recommended pad layout follows Taiwan Semiconductor's suggested footprint in the package outline drawing, and it carries moisture sensitivity level 1 (MSL-1), meaning no baking is required before reflow. The SMBJ28A's 0.090 g weight and UL 94V-0 molding compound support automated placement and high-reliability end-use environments.
SMBJ28A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-214AA, SMB
- Series:
- SMBJ
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 28V
- Voltage - Breakdown (Min):
- 31.1V
- Voltage - Clamping (Max) @ Ipp:
- 45.4V
- Current - Peak Pulse (10/1000µs):
- 13.3A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- Yes
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AA (SMBJ)
SMBJ28A FAQ
1.How can I place an order for SMBJ28A through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ28A 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 SMBJ28A reliable?
The price and inventory of SMBJ28A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ28A is usually 5 days.
3.What payment methods are accepted for SMBJ28A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ28A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ28A?
SMBJ28A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ28A 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 SMBJ28A?
For technical support, including SMBJ28A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ28A requirements.
6.How does Aetrix verify that SMBJ28A is sourced from the original manufacturer or authorized distributors?
All SMBJ28A 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 SMBJ28A meets industry standards.
7.What is the process for return or replacement of SMBJ28A?
All SMBJ28A units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ28A, 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 SMBJ28A part is unused and in its original packaging.
Return procedure for SMBJ28A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ28A 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…
