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Taiwan Semiconductor Corporation 1KSMB91AH
- Part No.:
- 1KSMB91AH
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
1KSMB91AH.pdf
- Description:
- TVS DIODE 77.8VWM 125VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:5,860
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Product details
Overview
1KSMB91AH from Taiwan Semiconductor is a unidirectional 1000W surface-mount Transient Voltage Suppressor (TVS) diode in DO-214AA (SMB) package, with breakdown voltage 86.5–95.5 V, stand-off voltage 77.8 V, clamping voltage 125 V at 8.0 A peak pulse current, and AEC-Q101 qualification for automotive-grade reliability.
For engineers reviewing the 1KSMB91AH datasheet, 1KSMB91AH pinout, 1KSMB91AH application, or 1KSMB91AH equivalent, key selection criteria include unidirectional polarity, ISO 7637-2 Pulse 1/2a/2b/3a/3b compliance, 1.0 ps typical response time, glass-passivated junction, and moisture sensitivity level 1 - all critical for ESD and load-dump protection in automotive power electronics.
Technical Context
The 1KSMB91AH operates as a unidirectional avalanche diode designed to clamp transient overvoltages before they damage downstream circuitry. It features a single-die construction in DO-214AA package, with junction-to-lead thermal resistance of 20°C/W and maximum junction temperature of +175°C.
Its electrical behavior follows ANSI/IEEE C62.35 standards: breakdown voltage is measured at 1.0 mA test current with 30 ms square-wave pulse; clamping occurs at 125 V under 10/1000 µs waveform with 8.0 A peak impulse current; reverse leakage remains ≤1.0 µA at 77.8 V stand-off voltage.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBR min/max | 86.5 V / 95.5 V - defines minimum and maximum voltage at which avalanche conduction begins reliably at 1.0 mA |
| VWM | 77.8 V - maximum continuous reverse operating voltage without significant leakage |
| VC@IPP | 125 V @ 8.0 A - clamping voltage during 10/1000 µs transient, limiting stress on protected ICs |
| PPPSM | 1000 W - non-repetitive peak pulse power handling capability per standard waveform |
| TJ max | +175 °C - enables operation in under-hood automotive environments without derating |
| Response time | <1.0 ps - ensures suppression initiates before most fast transients propagate into sensitive nodes |
Pinout & Package
Package: DO-214AA (SMB), surface-mount, cathode-banded unidirectional configuration. Weight: 0.110 g. Molding compound meets UL 94V-0; matte tin-plated leads compliant with J-STD-002 solderability.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal during forward conduction | Connected to system ground or low-side return path in unidirectional TVS placement |
| Cathode | Current exit terminal during reverse-biased clamping | Connected to protected line (e.g., battery rail); marked by band on package body |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive applications including engine control, body electronics, and infotainment power rails |
| Glass passivated chip junction | Enhances long-term reliability and humidity resistance versus epoxy-passivated alternatives |
| ISO 7637-2 compliance (Pulse 1/2a/2b/3a/3b) | Meets full suite of automotive transient immunity requirements for 12 V systems |
| Moisture sensitivity level 1 | Enables direct placement without baking, reducing manufacturing overhead and floor-life constraints |
Applications
| Automotive Load-Dump Protection | Industrial Power Rail ESD Clamping |
|---|---|
Use Scenario: Protecting microcontroller power inputs during alternator load dump events in 12 V vehicle systems. IC Role / Device Role / Timing Role: Unidirectional TVS placed between battery rail and LDO input to clamp transients up to 125 V. Use Value: Prevents latch-up or permanent damage to 3.3 V/5 V logic supplies when subjected to ISO 7637-2 Pulse 5a (load dump). | Use Scenario: Safeguarding PLC I/O module power lines against electrostatic discharge in factory automation cabinets. IC Role / Device Role / Timing Role: Standoff-rated TVS on 24 V DC supply rail upstream of DC-DC converter. Use Value: Limits transient energy to <100 mJ while maintaining 77.8 V operational margin below system nominal voltage. |
| LED Driver Overvoltage Suppression | Automotive CAN Bus Power Line Protection |
Use Scenario: Shielding constant-current LED driver ICs from inductive kickback during PWM dimming in headlamp modules. IC Role / Device Role / Timing Role: TVS connected across driver output terminals to absorb flyback energy. Use Value: Clamps spikes within 1 ps to prevent gate oxide rupture in MOSFET-based drivers rated ≤100 V. | Use Scenario: Guarding 12 V supply to CAN transceiver against coupled transients from adjacent high-power solenoid switching. IC Role / Device Role / Timing Role: Unidirectional TVS on VCC pin of CAN controller, referenced to chassis ground. Use Value: Maintains CAN signal integrity by limiting supply rail excursions to ≤125 V during ISO 7637-2 Pulse 2b events. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ90A | Breakdown 90–100 V; clamping 129 V @ 7.8 A; same DO-214AA package | Marginally higher VBR and VC; lower IPP rating than 1KSMB91AH | Acceptable where 129 V clamping is acceptable and 7.8 A peak current suffices |
| 1.5SMC91A | Same VBR/VC specs but in larger DO-214AB (SMC) package; RθJA = 60°C/W vs. 100°C/W | Higher thermal mass allows longer pulse handling; less suitable for dense PCB layouts | Preferred for high-reliability industrial designs requiring extended surge endurance |
Compared with SMBJ90A and 1.5SMC91A, the 1KSMB91AH offers tighter VBR tolerance (±5.5% vs. ±6.7%), lower clamping voltage (125 V vs. 129 V), and superior thermal performance in constrained SMB footprints - making it optimal for space-limited automotive modules needing precise voltage clamping.
Availability
1KSMB91AH is available at Aetrix Electronics and suitable for automotive power management, industrial PLC I/O protection, and LED lighting surge suppression requiring stable component supply and AEC-Q101-compliant sourcing.
Supply support for 1KSMB91AH 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 validation capabilities.
The 1KSMB series is engineered specifically for automotive and industrial transient suppression, emphasizing robustness under ISO 7637-2 pulses, low leakage, and high surge current capability in compact SMB packages.
FAQ
What is the polarity configuration of the 1KSMB91AH?
The 1KSMB91AH is a unidirectional TVS diode, meaning it conducts only in reverse bias during overvoltage events. Its cathode is marked by a band on the DO-214AA package body, and it must be oriented with cathode toward the protected line and anode to ground. This configuration provides asymmetrical clamping optimized for DC power rail protection, unlike bidirectional variants (e.g., 1KSMB91CAH) used for AC or data-line applications.
Does the 1KSMB91AH meet automotive qualification standards?
Yes, the 1KSMB91AH is AEC-Q101 qualified and explicitly tested to meet ISO 7637-2 Pulse 1, 2a, 2b, 3a, and 3b transient immunity requirements for 12 V automotive systems. Its glass-passivated junction, moisture sensitivity level 1, and operation up to +175°C junction temperature confirm suitability for under-hood and body-control module deployments where reliability under thermal and electrical stress is critical.
What is the maximum clamping voltage of the 1KSMB91AH and under what test condition?
The maximum clamping voltage of the 1KSMB91AH is 125 V, measured at a peak pulse current (IPP) of 8.0 A using the standardized 10/1000 µs double-exponential waveform. This value represents the upper limit of voltage seen by downstream components during worst-case transients and is guaranteed across the full operating temperature range per the manufacturer's electrical specifications table.
Can the 1KSMB91AH be used in bidirectional signal line protection?
No, the 1KSMB91AH is strictly unidirectional and unsuitable for bidirectional signal lines such as USB, CAN, or RS-485. For those applications, the bidirectional variant 1KSMB91CAH must be selected. Using the 1KSMB91AH on AC or differential signals would result in forward conduction during half-cycles, causing malfunction or damage due to lack of symmetrical clamping capability.
What is the standoff voltage rating and why does it matter for circuit design?
The standoff voltage (VWM) of the 1KSMB91AH is 77.8 V - the maximum continuous reverse voltage it can withstand without exceeding 1.0 µA leakage. This rating ensures reliable operation on 72 V nominal systems (e.g., commercial vehicle batteries) while preserving margin against ripple and tolerance drift. Exceeding VWM risks premature conduction and increased power loss, so designers must verify system operating voltage stays ≥15% below this value during all conditions.
1KSMB91AH 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):
- 77.8V
- Voltage - Breakdown (Min):
- 86.5V
- Voltage - Clamping (Max) @ Ipp:
- 125V
- Current - Peak Pulse (10/1000µs):
- 8A
- 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)
1KSMB91AH FAQ
1.How can I place an order for 1KSMB91AH through Aetrix?
Please submit a Request for Quotation (RFQ) for 1KSMB91AH 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 1KSMB91AH reliable?
The price and inventory of 1KSMB91AH are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1KSMB91AH is usually 5 days.
3.What payment methods are accepted for 1KSMB91AH?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1KSMB91AH transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1KSMB91AH?
1KSMB91AH orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1KSMB91AH 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 1KSMB91AH?
For technical support, including 1KSMB91AH datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1KSMB91AH requirements.
6.How does Aetrix verify that 1KSMB91AH is sourced from the original manufacturer or authorized distributors?
All 1KSMB91AH 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 1KSMB91AH meets industry standards.
7.What is the process for return or replacement of 1KSMB91AH?
All 1KSMB91AH units undergo pre-shipment inspection (PSI). If there is an issue with 1KSMB91AH, 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 1KSMB91AH part is unused and in its original packaging.
Return procedure for 1KSMB91AH:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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