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Microchip Technology 1N8149USE3/TR
- Part No.:
- 1N8149USE3/TR
- Manufacturer:
- Microchip Technology
- Category:
- TVS Diodes
- Package:
- SQ-MELF, A
- Datasheet:
-
1N8149USE3/TR.pdf
- Description:
- LOW CAPACITANCE TVS
- Quantity:
- Payment:
- Shipping:
Inventory:2,670
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Product details
Overview
1N8149USE3/TR from Microsemi is a voidless-hermetically-sealed unidirectional transient voltage suppressor (TVS) with 4 pF capacitance, 6.8 V working standoff voltage (VWM), and 150 W peak pulse power at 10/1000 µs. It features an internal series rectifier diode for ultra-low capacitance and Category 1 metallurgical bonding for high-reliability aerospace and defense applications.
For engineers reviewing the 1N8149USE3/TR datasheet, 1N8149USE3/TR pinout, 1N8149USE3/TR application, or 1N8149USE3/TR equivalent, this device is selected for ESD/EFT protection per IEC61000-4-2/4-4, secondary lightning protection per IEC61000-4-5, and high-frequency signal line protection where low capacitance and radiation hardness are critical.
Technical Context
The 1N8149USE3/TR implements a unique dual-element structure: a TVS junction in series with a reverse-oriented rectifier diode, enabling 4 pF total capacitance while maintaining unidirectional clamping behavior. Its breakdown voltage is 7.79 V minimum at 10 mA, with clamping voltage of 12.8 V at 11.7 A peak impulse current.
Designed for hermetic glass packaging with tungsten slugs and axial-leaded terminals, it operates across –55 °C to +175 °C junction temperature and exhibits inherent radiation hardness per MicroNote 050. The RoHS-compliant e3 marking confirms matte tin plating over copper leads.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 6.8 V - Maximum continuous reverse standoff voltage before conduction begins; sets operating margin for protected signal lines. |
| V(BR) min | 7.79 V at 10 mA - Minimum breakdown voltage threshold; ensures reliable triggering above system operating voltage. |
| VC | 12.8 V at IPP = 11.7 A - Clamping voltage during 10/1000 µs surge; defines worst-case voltage seen by downstream circuitry. |
| CT | 4 pF - Total capacitance at 0 V; enables use on >1 GHz RF paths and high-speed data lines without signal degradation. |
| PPP | 150 W at 25 °C - Peak pulse power rating; supports robust protection against IEC61000-4-5 Level 3 surges (1 kV/2 Ω). |
| TJ range | –55 °C to +175 °C - Extended junction temperature range; qualified for military, avionics, and downhole electronics. |
| Radiation Hardness | Inherently radiation hard - No TID or SEE derating required per Microsemi MicroNote 050; eliminates need for shielding or redundancy in space-grade designs. |
Pinout & Package
Package: Axial-leaded, voidless hermetically sealed hard glass case with tungsten slugs; cathode band marking; RoHS-compliant matte tin plating over copper leads; weight ≈ 340 mg.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Positive terminal under forward bias | Connected to protected line side; conducts only during reverse-transient clamping when cathode is held higher. |
| Cathode | Negative terminal; marked with band | Connected to ground or reference rail; establishes unidirectional clamping path and defines polarity of protection. |
Key Features
| Feature | Design Value |
|---|---|
| Low capacitance architecture | 4 pF achieved via integrated series rectifier diode - preserves signal integrity on RF, Ethernet, and USB 2.0+ interfaces. |
| Category 1 metallurgical bond | Internal high-reliability bond per MIL-STD-780 - eliminates wirebond fatigue and ensures >100,000 thermal cycles in mission-critical systems. |
| Voidless hermetic seal | Hard-glass enclosure with zero internal voids - prevents moisture ingress and parametric drift over 20+ year field life. |
| ESD/EFT compliance | Validated per IEC61000-4-2 (±15 kV air/±8 kV contact) and IEC61000-4-4 (40 A, 5/50 ns) - meets industrial and telecom immunity requirements. |
Applications
| Avionics Data Bus Protection | Military Radio Front-End |
|---|---|
Use Scenario: Protecting ARINC 429 or MIL-STD-1553B differential receivers from induced transients during lightning strike events. IC Role / Device Role / Timing Role: Unidirectional TVS placed on each data line to clamp surges before they reach receiver input stages. Use Value: 4 pF capacitance avoids signal rise-time degradation; 12.8 V clamping ensures receiver ICs remain within absolute maximum ratings. | Use Scenario: Shielding HF/VHF transceiver antenna ports from electrostatic discharge and nearby EMP coupling. IC Role / Device Role / Timing Role: Standoff-mounted TVS on coaxial feedline input to absorb fast-rising ESD pulses without loading RF impedance. Use Value: Hermetic glass package withstands thermal shock during high-duty-cycle transmission; radiation hardness prevents latch-up in airborne platforms. |
| Satellite Telemetry Interface | Downhole Oilfield Sensor Node |
Use Scenario: Safeguarding RS-422 telemetry links between satellite subsystems exposed to cosmic radiation and power bus switching noise. IC Role / Device Role / Timing Role: Point-of-entry TVS on differential pair inputs to suppress common-mode surges while preserving skew matching. Use Value: Inherent radiation hardness eliminates need for redundant protection; –55 °C to +175 °C operation covers orbital thermal extremes. | Use Scenario: Protecting pressure/temperature sensor analog outputs in high-temperature (>150 °C) oil well logging tools subject to cable discharge events. IC Role / Device Role / Timing Role: Axial-leaded TVS soldered directly to sensor PCB output traces to shunt transient energy before op-amp inputs. Use Value: Voidless hermetic seal prevents outgassing in vacuum environments; 175 °C max junction temperature matches downhole thermal profiles. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMCJ6.8A | Surface-mount DO-214AB package; 6.8 V VWM; 100 W PPP; 65 pF capacitance - 16× higher than 1N8149USE3/TR. | Not suitable for >100 MHz signal paths; limited to lower-frequency power/signal rails due to capacitance. | Select when board space is constrained and RF performance is not required. |
| 1N6105A | Axial-leaded, 6.8 V VWM, 150 W PPP, but 100 pF capacitance and non-hermetic epoxy package - no radiation hardness or Category 1 bond. | Lacks qualification for aerospace/military use; unsuitable for long-life sealed systems or radiation environments. | Select for cost-sensitive commercial industrial applications where reliability and lifetime are secondary. |
Compared with SMCJ6.8A and 1N6105A, the 1N8149USE3/TR delivers uniquely low 4 pF capacitance in a hermetic, radiation-hard, Category 1-bonded axial package - making it irreplaceable for RF front-ends, avionics buses, and space-grade telemetry where signal fidelity and long-term reliability are non-negotiable.
Availability
1N8149USE3/TR is available at Aetrix Electronics and suitable for avionics data bus protection, military radio front-end hardening, and satellite telemetry interface design requiring stable component supply across extended product lifecycles.
Supply support for 1N8149USE3/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) is a U.S.-based semiconductor company specializing in high-reliability, radiation-hardened, and aerospace-grade components.
The 1N8149USE3/TR belongs to Microsemi's legacy "LDS" series of hermetic TVS diodes, engineered specifically for mission-critical protection in defense, space, and nuclear instrumentation systems where failure is not an option.
FAQ
What is the clamping voltage of the 1N8149USE3/TR at its rated peak impulse current?
The 1N8149USE3/TR has a maximum clamping voltage (VC) of 12.8 V at a peak impulse current (IPP) of 11.7 A under the standard 10/1000 µs waveform. This value is measured at 25 °C and defines the upper voltage limit imposed on protected circuits during surge events. The 1N8149USE3/TR maintains this clamping performance across its full operating temperature range due to its hermetic construction and stable junction characteristics.
Is the 1N8149USE3/TR suitable for bidirectional transient protection?
No - the 1N8149USE3/TR is strictly unidirectional. For bidirectional protection, two 1N8149USE3/TR devices must be connected in anti-parallel, as documented in Figure 5 of the Microsemi datasheet. This configuration doubles the effective capacitance to 8 pF but retains the same clamping performance in both polarities. The 1N8149USE3/TR itself does not conduct in forward bias beyond its 1.0 W steady-state rating.
Does the 1N8149USE3/TR meet IEC61000-4-5 for lightning surge immunity?
Yes - the 1N8149USE3/TR provides secondary lightning protection per select levels of IEC61000-4-5, validated through its 150 W peak pulse power rating at 10/1000 µs and clamping voltage of 12.8 V. When used with appropriate series impedance (e.g., 2 Ω source), it limits induced surge voltages to safe levels for downstream receivers. Its hermetic seal ensures consistent performance across repeated surges without parameter drift.
What is the meaning of "e3" in the 1N8149USE3/TR part number?
The "e3" suffix in 1N8149USE3/TR indicates RoHS-compliant matte tin plating over copper leads, per JEDEC Standard J-STD-609. This replaces traditional tin/lead plating while maintaining solderability and thermal cycling reliability. The "TR" denotes tape-and-reel packaging per EIA-296, and "US" identifies the axial-leaded hermetic glass package variant. The full designation confirms full compliance with environmental and mechanical specifications in the original Microsemi LDS datasheet.
How does the 4 pF capacitance of the 1N8149USE3/TR compare to standard TVS diodes?
The 4 pF capacitance of the 1N8149USE3/TR is the lowest commercially available for a 150 W-rated TVS diode - typically 10–20× lower than standard axial or surface-mount alternatives (e.g., 65–100 pF). This is achieved via Microsemi's patented series-rectifier architecture. As a result, the 1N8149USE3/TR introduces negligible loading on high-speed signals up to 2 GHz, unlike conventional TVS devices that distort eye diagrams or attenuate RF carriers.
1N8149USE3/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
1N8149USE3/TR FAQ
1.How can I place an order for 1N8149USE3/TR through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N8149USE3/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 1N8149USE3/TR reliable?
The price and inventory of 1N8149USE3/TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N8149USE3/TR is usually 5 days.
3.What payment methods are accepted for 1N8149USE3/TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N8149USE3/TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N8149USE3/TR?
1N8149USE3/TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N8149USE3/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 1N8149USE3/TR?
For technical support, including 1N8149USE3/TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N8149USE3/TR requirements.
6.How does Aetrix verify that 1N8149USE3/TR is sourced from the original manufacturer or authorized distributors?
All 1N8149USE3/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 1N8149USE3/TR meets industry standards.
7.What is the process for return or replacement of 1N8149USE3/TR?
All 1N8149USE3/TR units undergo pre-shipment inspection (PSI). If there is an issue with 1N8149USE3/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 1N8149USE3/TR part is unused and in its original packaging.
Return procedure for 1N8149USE3/TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N8149USE3/TR Tags
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onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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Diodes Incorporated
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Diodes Incorporated
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Diodes Incorporated
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onsemi
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Diodes Incorporated
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Diodes Incorporated
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Nexperia USA Inc.
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Toshiba Semiconductor and Storage
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Diodes Incorporated
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