My Inquiry
My Account
Taiwan Semiconductor Corporation SMBJ20AH
- Part No.:
- SMBJ20AH
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ20AH.pdf
- Description:
- TVS DIODE 20VWM 32.4VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:3,182
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMBJ20AH from Taiwan Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode in DO-214AA (SMB) package, rated for 600W peak pulse power, 20V working stand-off voltage (VWM), and 32.4V maximum clamping voltage (VC) at 19.4A peak impulse current - designed to protect automotive power electronics and industrial control inputs against ISO 7637-2 Pulse 1/2a/2b/3a/3b transients.
For engineers reviewing the SMBJ20AH datasheet, SMBJ20AH pinout, SMBJ20AH application, or SMBJ20AH equivalent, this device is selected for high-reliability 24V system rail protection where low clamping voltage, sub-1ps response time, and AEC-Q101 qualification are required - especially in ECU input conditioning, sensor interface surge suppression, and DC-DC converter front-end protection.
Technical Context
The SMBJ20AH operates as a unidirectional avalanche diode with glass-passivated junction, enabling fast transient response (<1.0ps) and stable breakdown behavior under repetitive surge stress. Its 22.2–24.5V breakdown voltage (VBR) at 1mA test current ensures precise triggering above nominal 20V rail voltage while maintaining <1μA leakage at VWM.
Thermally, it features 10°C/W junction-to-case and 55°C/W junction-to-ambient thermal resistance, supporting continuous operation up to +150°C junction temperature. The device meets JESD201 Class 2 whisker resistance and UL 94V-0 flammability requirements, confirming suitability for automated SMT assembly in harsh-environment automotive modules.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 20 V - Maximum continuous reverse operating voltage before clamping begins; sets safe margin above 24V nominal supply rails. |
| VBR min/max | 22.2 / 24.5 V @ 1 mA - Confirmed avalanche onset range ensures reliable turn-on without premature conduction during normal operation. |
| VC @ IPP | 32.4 V @ 19.4 A - Clamping voltage limits downstream IC stress during 10/1000µs transients; enables robust protection of 33V-tolerant interfaces. |
| PPK | 600 W - Peak pulse power rating per 10/1000µs waveform defines maximum transient energy absorption capability. |
| ID @ VWM | <1 µA - Ultra-low leakage preserves signal integrity and minimizes standby power loss in always-on circuits. |
| TJ max | +150 °C - Enables deployment in under-hood automotive environments and industrial enclosures without derating. |
| Package | DO-214AA (SMB) - Standardized surface-mount outline compatible with IPC-7351B footprint; supports automated pick-and-place. |
Pinout & Package
DO-214AA (SMB) package: molded plastic case with matte tin-plated leads; cathode indicated by band marking; polarity-critical for unidirectional operation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side reference terminal | Connected to ground or return path; forms current sink during transient clamp event. |
| Cathode | Protected line input terminal | Connected to protected node (e.g., 24V rail or sensor input); conducts avalanche current when V > VBR. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive-grade reliability including temperature cycling, HTRB, and ESD testing - suitable for Tier-1 ECU designs. |
| Clamping voltage ≤32.4V | Ensures protected ICs (e.g., CAN transceivers, microcontrollers) remain below absolute maximum ratings during ISO 7637-2 Pulse 2b (inductive load dump). |
| Response time <1.0 ps | Fast enough to suppress EFT bursts (IEC 61000-4-4) before sensitive analog front-ends or ADC references are disturbed. |
| Moisture sensitivity level 1 | Eliminates bake requirements prior to reflow; supports standard SMT process flow without handling restrictions. |
| RoHS & halogen-free | Complies with IEC 61249-2-21 and EU RoHS Directive - required for global automotive and industrial market access. |
Applications
| Automotive Body Control Module (BCM) | Industrial PLC Digital Input Protection |
|---|---|
Use Scenario: Protecting 24V supply inputs of BCM microcontrollers and driver ICs against load-dump transients and alternator ripple. IC Role / Device Role: Unidirectional TVS placed between 24V rail and ground, clamping surges exceeding 24V to ≤32.4V. Use Value: Prevents latch-up or permanent damage to 33V-rated MCU I/O and power management ICs during ISO 7637-2 Pulse 5a events. |
Use Scenario: Shielding 24V digital input channels on PLC I/O cards from field-wiring induced transients and EFT coupling. IC Role / Device Role: Front-end surge limiter on optocoupler input side, absorbing energy before signal conditioning circuitry. Use Value: Maintains channel integrity during IEC 61000-4-4 Level 4 EFT testing (4kV contact discharge) without false triggering or degradation. |
| Automotive Lighting Control Unit | DC-DC Converter Input Stage |
Use Scenario: Safeguarding LED driver ICs and MOSFET gate drivers in headlamp modules exposed to battery disconnect transients. IC Role / Device Role: Rail clamp on 12V/24V supply line feeding buck controllers and high-side switches. Use Value: Limits voltage overshoot to <33V during ISO 7637-2 Pulse 1 (inductive switch-off), preserving gate oxide integrity. |
Use Scenario: Protecting synchronous buck controller ICs from input voltage spikes caused by upstream relay switching or cable inductance. IC Role / Device Role: Primary overvoltage clamp on VIN pin of DC-DC ICs operating from 24V vehicle battery. Use Value: Ensures VC remains below 36V - within safe operating area of common 36V-input buck controllers like LM5143A. |
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 SMAJ20A | Same DO-214AC (SMA) package; 33.2V clamping at 18.8A; slightly higher VC (+0.8V) and lower IPP (-0.6A). | Compatible for non-AEC-Q101 industrial use; lacks automotive qualification and moisture level 1 rating. | Select if cost-sensitive and automotive qualification not required; verify PCB pad compatibility (SMA vs SMB). |
| ON Semiconductor 1.5SMC20A | DO-214AB (SMC) package; 32.4V clamping at 19.4A; identical electrical specs but larger footprint and 1.5W steady-state rating. | Preferred where higher thermal mass is needed for sustained surge duty cycles; not suitable for space-constrained SMB layouts. | Choose when board layout allows SMC footprint and enhanced thermal dissipation is prioritized over size. |
Compared with SMAJ20A and 1.5SMC20A, the SMBJ20AH delivers identical clamping performance in a smaller DO-214AA package with AEC-Q101 validation and moisture level 1 - making it the optimal choice for automotive SMT designs requiring zero rework risk and guaranteed qualification compliance.
Availability
SMBJ20AH is available at Aetrix Electronics and suitable for automotive body electronics, industrial PLC input stages, lighting control units, and DC-DC converter front-end protection requiring stable component supply across multi-year production programs.
Supply support for SMBJ20AH 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 Taiwanese 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 12V/24V automotive systems - emphasizing low clamping voltage, high surge robustness, and seamless SMT manufacturability.
FAQ
What is the clamping voltage of SMBJ20AH and how is it measured?
The SMBJ20AH has a maximum clamping voltage (VC) of 32.4 V, measured at 19.4 A peak impulse current using a standardized 10/1000 µs double-exponential waveform per ANSI/IEEE C62.35. This value represents the upper limit of voltage seen by downstream circuitry during worst-case transient events - critical for ensuring protected ICs remain within their absolute maximum ratings. The SMBJ20AH achieves this clamping performance while maintaining tight VBR tolerance (22.2–24.5 V) and ultra-low leakage.
Is SMBJ20AH suitable for bidirectional transient protection?
No, SMBJ20AH is a unidirectional TVS diode intended only for DC rail protection with defined polarity. For bidirectional applications such as AC lines or data bus protection, Taiwan Semiconductor offers the SMBJ20CAH variant - which uses the same DO-214AA package but provides symmetrical clamping in both directions. Using SMBJ20AH in reverse-biased configurations risks permanent damage due to lack of reverse avalanche capability.
Does SMBJ20AH meet automotive qualification standards?
Yes, SMBJ20AH is explicitly AEC-Q101 qualified per the manufacturer's documentation, covering stress tests including high-temperature reverse bias (HTRB), temperature cycling, and mechanical shock. It also complies with ISO 7637-2 Pulse 1/2a/2b/3a/3b immunity requirements - confirming its suitability for engine control units, body modules, and other automotive subsystems where reliability under harsh electrical conditions is mandatory.
What is the thermal resistance profile of SMBJ20AH and why does it matter?
SMBJ20AH has a junction-to-case thermal resistance (RθJC) of 10°C/W and junction-to-ambient resistance (RθJA) of 55°C/W. These values determine how effectively heat generated during surge events is transferred away from the silicon die. In high-duty-cycle or repeated transient scenarios, low RθJC enables efficient heat sinking through the PCB copper pour, while RθJA informs ambient temperature derating - both essential for sustaining 600W peak power capability without thermal runaway.
How does SMBJ20AH compare to SMBJ20H in terms of electrical performance?
SMBJ20AH offers tighter breakdown voltage tolerance (22.2–24.5 V) versus SMBJ20H (22.2–27.1 V), resulting in more predictable clamping onset and reduced risk of premature conduction. Its clamping voltage is also lower (32.4 V vs 35.8 V at same IPP), improving protection margin for 33V-rated components. Both share identical package, power rating, and AEC-Q101 qualification - making SMBJ20AH the preferred choice where precision clamping and lower VC are design priorities.
SMBJ20AH 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):
- 20V
- Voltage - Breakdown (Min):
- 22.2V
- Voltage - Clamping (Max) @ Ipp:
- 32.4V
- Current - Peak Pulse (10/1000µs):
- 19.4A
- 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)
SMBJ20AH FAQ
1.How can I place an order for SMBJ20AH through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ20AH 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 SMBJ20AH reliable?
The price and inventory of SMBJ20AH are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ20AH is usually 5 days.
3.What payment methods are accepted for SMBJ20AH?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ20AH transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ20AH?
SMBJ20AH orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ20AH 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 SMBJ20AH?
For technical support, including SMBJ20AH datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ20AH requirements.
6.How does Aetrix verify that SMBJ20AH is sourced from the original manufacturer or authorized distributors?
All SMBJ20AH 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 SMBJ20AH meets industry standards.
7.What is the process for return or replacement of SMBJ20AH?
All SMBJ20AH units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ20AH, 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 SMBJ20AH part is unused and in its original packaging.
Return procedure for SMBJ20AH:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ20AH 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…
