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Microchip Technology MQ1N8149US/TR
- Part No.:
- MQ1N8149US/TR
- Manufacturer:
- Microchip Technology
- Category:
- TVS Diodes
- Package:
- SQ-MELF, A
- Datasheet:
-
MQ1N8149US/TR.pdf
- Description:
- LOW CAPACITANCE TVS
- Quantity:
- Payment:
- Shipping:
Inventory:8,336
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Product details
Overview
MQ1N8149US/TR from Microsemi is a voidless-hermetically-sealed unidirectional transient voltage suppressor (TVS) diode designed for high-reliability, high-frequency signal line protection. It delivers 150 W peak pulse power at 10/1000 µs, 4 pF capacitance, and 6.8 V working standoff voltage (VWM), with clamping voltage of 12.8 V at 11.7 A peak surge current - ideal for ESD/EFT protection in aerospace data links.
For engineers reviewing the MQ1N8149US/TR datasheet, MQ1N8149US/TR pinout, MQ1N8149US/TR application, or MQ1N8149US/TR equivalent, key selection criteria include low-capacitance transient suppression, hermetic glass package robustness, Category 1 metallurgical bonding, IEC61000-4-2/4-4 compliance, and axial-leaded through-hole mounting compatibility.
Technical Context
The MQ1N8149US/TR integrates a unique series-opposed rectifier diode to achieve ultra-low 4 pF capacitance while maintaining unidirectional TVS functionality. Its hard-glass hermetic construction with tungsten slugs enables operation from –55 °C to +175 °C and supports MIL-STD-750 Method 1020 ESD insensitivity.
It operates as a clamping device with 6.8 V working standoff voltage (VWM), 7.79 V minimum breakdown voltage (V(BR)) at 10 mA, and 12.8 V maximum clamping voltage (VC) at 11.7 A peak impulse current (IPP), delivering 150 W peak pulse power under standard 10/1000 µs waveform conditions.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 6.8 V - Maximum continuous reverse-bias voltage before leakage exceeds 20 µA; sets operating margin for protected signal lines. |
| V(BR) min | 7.79 V at 10 mA - Confirmed breakdown threshold ensuring reliable turn-on during transients above nominal rail. |
| VC @ IPP | 12.8 V at 11.7 A - Clamped voltage level limiting downstream IC stress during 150 W surge events. |
| Capacitance | 4 pF at 0 V - Enables use in >1 GHz RF/data paths without signal integrity degradation. |
| PPP | 150 W at 10/1000 µs - Sustains high-energy lightning-induced surges per IEC61000-4-5 Level 3. |
| TJ range | –55 °C to +175 °C - Supports deployment in avionics, downhole, and engine-control environments. |
| RθJA | 150 °C/W - Thermal resistance defines derating requirement above 25 °C ambient for sustained power handling. |
Pinout & Package
MQ1N8149US/TR uses an axial-leaded, hermetically sealed hard-glass package with cathode band marking. Leads are tin/lead or RoHS-compliant matte tin over copper; weight ≈340 mg; dimensions per Microsemi drawing: BD = 0.060–0.085", BL = 0.106–0.175", LD = 0.028–0.032", LL = 0.800–1.300".
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Transient current sink path during forward conduction | Connected to protected line; conducts only during positive overvoltage events relative to cathode. |
| Cathode | Reference terminal with polarity band marking | Connected to system ground or lower-potential rail; defines unidirectional clamping direction. |
Key Features
| Feature | Design Value |
|---|---|
| Voidless hermetic seal | Eliminates internal moisture and particle migration, enabling >20-year field life in vacuum or high-humidity environments. |
| Category 1 metallurgical bond | Internal tungsten-copper interconnect meets MIL-PRF-19500 reliability requirements for space-grade components. |
| Triple-layer passivation | Enhances surface insulation stability and prevents leakage drift under high humidity or bias stress. |
| Low 4 pF capacitance | Preserves signal rise time and impedance matching in USB 3.0, RS-485, and MIL-STD-1553B data buses. |
Applications
| Aerospace Data Bus Protection | Military Radio Front-End |
|---|---|
Use Scenario: Protecting MIL-STD-1553B stubs against induced lightning transients on aircraft avionics bays. IC Role / Device Role / Timing Role: Unidirectional clamping TVS placed between bus transceiver and connector interface. Use Value: 4 pF capacitance avoids signal reflection; 12.8 V clamping ensures transceiver input stays below absolute max rating during 150 W surges. | Use Scenario: Shielding HF/VHF receiver LNA inputs from ESD and antenna-coupled EFT pulses in manpack radios. IC Role / Device Role / Timing Role: Low-capacitance TVS mounted directly at SMA connector feedthrough. Use Value: Hermetic glass package withstands thermal cycling in field-deployed units; 6.8 V VWM aligns with 5 V bias rails. |
| Downhole Sensor Interface | Industrial Ethernet PHY Port |
Use Scenario: Guarding RS-485 transceivers in oil/gas wellhead controllers exposed to electrostatic discharge and switching surges. IC Role / Device Role / Timing Role: Primary transient suppressor on differential pair, mounted before common-mode choke. Use Value: –55 °C to +175 °C junction range supports operation inside sealed pressure housings; 300 VWIB rating handles long-line inductive kickback. | Use Scenario: Securing 10/100BASE-TX PHY pins against ESD per IEC61000-4-2 Level 4 (8 kV contact). IC Role / Device Role / Timing Role: Point-of-entry TVS on transformer center-taps and data lines. Use Value: 4 pF capacitance prevents jitter accumulation across 100 m cable runs; RoHS-compliant plating satisfies industrial compliance mandates. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1.5KE6.8A | Higher 100 pF capacitance; DO-201 package; 600 W PPP but slower response due to junction capacitance. | Suitable for lower-speed power-line or AC-input protection, not RF/data lines. | Select only when capacitance <10 pF is not required and higher surge rating justifies larger footprint. |
| SMCJ6.8A | Surface-mount SMC package; 150 W PPP; 15 pF capacitance; JEDEC-standardized thermal profile. | Better suited for automated assembly and compact PCB layouts, but insufficient for >500 MHz signal integrity. | Prefer for volume production where reflow compatibility and board space outweigh ultra-low capacitance needs. |
Compared with 1.5KE6.8A and SMCJ6.8A, MQ1N8149US/TR uniquely satisfies high-frequency analog and digital interfaces requiring sub-5 pF capacitance, hermetic reliability, and extreme temperature resilience - making it irreplaceable in mission-critical RF and aerospace signal protection.
Availability
MQ1N8149US/TR is available at Aetrix Electronics and suitable for aerospace data bus protection, military radio front-end shielding, and downhole sensor interface applications requiring stable component supply and long-term obsolescence management.
Supply support for MQ1N8149US/TR 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
Microsemi Corporation (now part of Microchip Technology) designs high-reliability analog and mixed-signal semiconductors for aerospace, defense, and industrial markets, with emphasis on radiation-hardened and hermetically packaged components.
The MQ1N8149US/TR belongs to Microsemi's legacy 1N81xx series of voidless-hermetic TVS diodes, engineered specifically for ultra-low-capacitance transient suppression in high-frequency, high-reliability signal chains where failure is not an option.
FAQ
What is the maximum clamping voltage of MQ1N8149US/TR at its rated peak surge current?
The MQ1N8149US/TR has a maximum clamping voltage (VC) of 12.8 V at 11.7 A peak impulse current (IPP), measured under the standard 10/1000 µs waveform. This value ensures protected circuitry remains within safe voltage limits during transient events. The MQ1N8149US/TR achieves this performance while maintaining only 4 pF capacitance - critical for preserving signal fidelity in high-speed interfaces.
Is MQ1N8149US/TR compliant with IEC61000-4-2 and IEC61000-4-4 standards?
Yes, MQ1N8149US/TR provides ESD protection per IEC61000-4-2 and EFT protection per IEC61000-4-4, as confirmed in Microsemi's T4-LDS-xxxx datasheet. Its low 4 pF capacitance and fast response enable effective suppression without distorting test waveforms. The MQ1N8149US/TR is also validated for secondary lightning protection per select levels of IEC61000-4-5.
What is the operating temperature range for MQ1N8149US/TR?
The MQ1N8149US/TR is rated for junction and storage temperatures from –55 °C to +175 °C, enabled by its voidless hermetic glass package and Category 1 metallurgical bonds. This range supports deployment in extreme environments such as jet engine compartments, downhole tools, and satellite payload bays. The MQ1N8149US/TR maintains specified electrical parameters across this full range when properly derated.
Does MQ1N8149US/TR have RoHS compliance?
Yes, MQ1N8149US/TR is RoHS compliant, indicated by the "e3" suffix in its nomenclature. Its terminals feature RoHS-compliant matte tin plating over copper, meeting EU Directive 2011/65/EU requirements. Non-RoHS versions are available without the "e3" designation, but MQ1N8149US/TR specifically conforms to modern environmental regulations for industrial and aerospace supply chains.
How does the unique series-opposed diode structure in MQ1N8149US/TR reduce capacitance?
The MQ1N8149US/TR incorporates a rectifier diode in series and opposite polarity to the TVS junction, effectively canceling parasitic capacitance contributions and achieving a total device capacitance of just 4 pF. This architecture is distinct from standard TVS diodes and is explicitly documented in Microsemi's application schematics (Figure 4). The MQ1N8149US/TR leverages this design to enable protection in RF and high-speed digital circuits where conventional TVS devices would degrade signal integrity.
MQ1N8149US/TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Package/Case:
- SQ-MELF, A
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 6.8V
- Voltage - Breakdown (Min):
- 7.79V
- Voltage - Clamping (Max) @ Ipp:
- 12.8V
- Current - Peak Pulse (10/1000µs):
- 11.7A
- Power - Peak Pulse:
- 150W
- 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:
- A, SQ-MELF
MQ1N8149US/TR FAQ
1.How can I place an order for MQ1N8149US/TR through Aetrix?
Please submit a Request for Quotation (RFQ) for MQ1N8149US/TR 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 MQ1N8149US/TR reliable?
The price and inventory of MQ1N8149US/TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MQ1N8149US/TR is usually 5 days.
3.What payment methods are accepted for MQ1N8149US/TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MQ1N8149US/TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MQ1N8149US/TR?
MQ1N8149US/TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MQ1N8149US/TR 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 MQ1N8149US/TR?
For technical support, including MQ1N8149US/TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MQ1N8149US/TR requirements.
6.How does Aetrix verify that MQ1N8149US/TR is sourced from the original manufacturer or authorized distributors?
All MQ1N8149US/TR 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 MQ1N8149US/TR meets industry standards.
7.What is the process for return or replacement of MQ1N8149US/TR?
All MQ1N8149US/TR units undergo pre-shipment inspection (PSI). If there is an issue with MQ1N8149US/TR, 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 MQ1N8149US/TR part is unused and in its original packaging.
Return procedure for MQ1N8149US/TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MQ1N8149US/TR Tags
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ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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onsemi
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Diodes Incorporated
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D5V0P1B2LP-7B
Diodes Incorporated
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DESD5V0U1BA-7
Diodes Incorporated
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ESD5Z5.0T1G
onsemi
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DESD5V0U1BB-7
Diodes Incorporated
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D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
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DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
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Diodes Incorporated
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