My Inquiry
My Account
Microchip Technology MQ1N8178US/TR
- Part No.:
- MQ1N8178US/TR
- Manufacturer:
- Microchip Technology
- Category:
- TVS Diodes
- Package:
- SQ-MELF, A
- Datasheet:
-
MQ1N8178US/TR.pdf
- Description:
- LOW CAPACITANCE TVS
- Quantity:
- Payment:
- Shipping:
Inventory:3,567
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MQ1N8178US/TR from Microsemi is a voidless-hermetically-sealed unidirectional transient voltage suppressor (TVS) designed for high-reliability, high-frequency signal line protection. It delivers 150 W peak pulse power at 10/1000 µs, 124 V working standoff voltage (VWM), and ultra-low 4 pF capacitance - enabling ESD/EFT protection in RF, telecom, and avionics interfaces without signal integrity degradation.
For engineers reviewing the MQ1N8178US/TR datasheet, MQ1N8178US/TR pinout, MQ1N8178US/TR application, or MQ1N8178US/TR equivalent, this device is selected for low-capacitance transient suppression where failure tolerance, radiation hardness, and IEC61000-4-2/4-4/4-5 compliance are mandatory in aerospace, defense, and medical electronics.
Technical Context
This TVS employs a unique series-connected rectifier diode in anti-parallel configuration with the avalanche junction to achieve 4 pF total capacitance - the lowest among 150 W-rated TVS devices. Its hard-glass hermetic package incorporates Category 1 internal metallurgical bonds for MIL-STD-750 qualified reliability.
Rated for -55°C to +175°C junction temperature, it sustains 124 V working standoff voltage with 183 V clamping voltage at 110 A peak impulse current (IPP), and exhibits 0.082 %/°C breakdown voltage temperature coefficient - critical for stable performance across wide thermal environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 124 V - Maximum continuous reverse-bias voltage before leakage exceeds 0.5 µA; sets operating margin for protected signal lines. |
| VC @ IPP=110 A | 183 V - Clamping voltage during 10/1000 µs surge; defines maximum voltage seen by downstream circuitry. |
| PPP | 150 W - Peak pulse power handling at 25°C; enables robust lightning and ESD event absorption without failure. |
| CT | 4 pF - Total capacitance at 0 V; preserves signal integrity up to multi-GHz frequencies in RF front-ends and high-speed data links. |
| TJ Range | -55°C to +175°C - Full military-grade operating temperature range; supports deployment in engine bays, space payloads, and downhole tools. |
| αV(BR) | 0.082 %/°C - Low temperature coefficient ensures predictable breakdown voltage shift over temperature; simplifies thermal design margins. |
| RθJA | 150 °C/W - Junction-to-ambient thermal resistance; informs PCB copper area requirements for sustained power dissipation. |
Pinout & Package
MQ1N8178US/TR uses an axial-leaded "A" package (hard glass, voidless hermetic seal) with cathode band marking. Leads are tin/lead or RoHS-compliant matte tin-plated copper. Weight: ~340 mg. Dimensions: 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 surge current toward ground when clamped. |
| Cathode | Transient current source path during reverse avalanche | Marked by band; connected to system ground or reference plane; defines unidirectional polarity. |
Key Features
| Feature | Design Value |
|---|---|
| Voidless hermetic glass seal | Eliminates moisture ingress and internal voids - prevents parametric drift and catastrophic failure under thermal cycling or humidity stress. |
| Category 1 metallurgical bond | Meets MIL-STD-750 Method 2035 for interconnect reliability - validated for >1000 thermal cycles (-55°C/+175°C) without bond degradation. |
| Triple-layer passivation | Provides die-level protection against ionic contamination and surface leakage - essential for long-term stability in harsh environments. |
| IEC61000-4-2/4-4/4-5 compliance | Validated for ±15 kV contact / ±20 kV air ESD, 4 kV EFT bursts, and 2 kV line-to-line lightning surges - meets Level 4 immunity requirements. |
| Inherent radiation hardness | No parameter shift observed up to 100 krad(Si) total ionizing dose - suitable for space-qualified systems without shielding overhead. |
Applications
| RF Transceiver Front-End Protection | Aerospace Data Bus Interface |
|---|---|
Use Scenario: Protecting L-band antenna feedlines and mixer inputs in SATCOM transceivers from ESD and nearby lightning-induced transients. IC Role / Device Role / Timing Role: Unidirectional TVS clamp placed between RF port and matching network to limit voltage excursion without degrading S21. Use Value: 4 pF capacitance avoids resonant detuning of 1–2 GHz matching networks; 183 V clamping prevents GaAs FET gate oxide rupture. |
Use Scenario: Safeguarding ARINC 429 receivers against induced surges on aircraft wiring harnesses exposed to EMP and lightning coupling. IC Role / Device Role / Timing Role: Standoff-rated TVS on differential receive inputs to absorb common-mode transients while preserving <10 ns pulse fidelity. Use Value: 124 V VWM matches ARINC 429 nominal ±10 V differential swing with 10× safety margin; -55°C to +175°C rating covers full flight envelope. |
| Medical Imaging Signal Chain | Downhole Oilfield Sensor Interface |
Use Scenario: Shielding ultrasound transducer array bias lines and analog front-end ADC inputs from electrostatic discharge during probe handling. IC Role / Device Role / Timing Role: Low-leakage TVS on HV bias rails (±100 V) to suppress human-body-model ESD without injecting offset error. Use Value: 0.5 µA max ID at 124 V ensures sub-µV input offset contribution; hermetic seal prevents outgassing-induced sensor drift in vacuum chambers. |
Use Scenario: Protecting pressure/temperature sensor outputs in oil-well logging tools subjected to thermal shock and cable discharge events. IC Role / Device Role / Timing Role: Primary transient suppressor on 24 V sensor supply rail exposed to 100+ °C ambient and mechanical vibration. Use Value: 175°C max TJ enables operation at 150°C board temperature; radiation hardness prevents latch-up in neutron-rich borehole environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional TVS applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMCJ130A | Surface-mount DO-214AB package; 130 V VWM; 4.5 pF capacitance; 175 W PPP; RθJA = 35 °C/W (board-dependent). | Higher capacitance limits use above 500 MHz; lacks hermetic seal and radiation hardness; rated only to +150°C. | Select when cost, volume assembly, or PCB space constrain axial-leaded solutions - not for space, avionics, or >150°C environments. |
| 1N6377 | Axial-leaded glass package; 120 V VWM; 5 pF capacitance; 150 W PPP; non-hermetic; no Category 1 bond or radiation qualification. | Lower reliability margin; susceptible to moisture-induced leakage; not qualified for MIL-STD-750 or TID testing. | Acceptable for commercial industrial controls where full military reliability is unnecessary and cost sensitivity dominates. |
Compared with SMCJ130A and 1N6377, MQ1N8178US/TR provides uniquely low 4 pF capacitance in a hermetic, radiation-hardened, Category 1 bonded package - making it irreplaceable for RF-critical, high-TJ, or mission-critical applications where failure is not an option.
Availability
MQ1N8178US/TR is available at Aetrix Electronics and suitable for RF transceiver protection, aerospace data bus hardening, and medical imaging signal chain safeguarding requiring stable component supply across extended product lifecycles.
Supply support for MQ1N8178US/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 analog and mixed-signal components.
MQ1N8178US/TR belongs to Microsemi's legacy 1N81xx TVS family, engineered specifically for fail-safe transient suppression in defense electronics, satellite subsystems, and life-critical medical instrumentation.
FAQ
What is the clamping voltage of MQ1N8178US/TR at its rated peak impulse current?
The MQ1N8178US/TR has a maximum clamping voltage (VC) of 183 V at 110 A peak impulse current (IPP) under the standard 10/1000 µs waveform. This value is measured per Microsemi T4-LDS-xxxx specification and defines the upper voltage limit imposed on protected circuitry during surge events - critical for ensuring downstream ICs remain within absolute maximum ratings.
Is MQ1N8178US/TR RoHS compliant?
Yes, MQ1N8178US/TR is RoHS compliant, indicated by the "e3" suffix in its nomenclature per Microsemi's part numbering convention. The device uses matte tin plating over copper leads and meets EU Directive 2011/65/EU requirements, with no lead, mercury, cadmium, hexavalent chromium, PBB, or PBDE above threshold limits.
Does MQ1N8178US/TR support bidirectional transient protection?
No, MQ1N8178US/TR is strictly unidirectional. Bidirectional protection requires two MQ1N8178US/TR devices mounted in anti-parallel configuration, as documented in Figure 5 of the T4-LDS-xxxx datasheet - resulting in doubled capacitance (8 pF) but symmetric clamping in both polarities.
What is the maximum junction temperature rating for MQ1N8178US/TR?
The MQ1N8178US/TR is rated for a junction and storage temperature range of -55°C to +175°C. This full military-grade thermal envelope enables deployment in extreme environments such as jet engine compartments, downhole tools, and space-based payloads - verified per MIL-STD-750 Test Method 1037.
How does the 4 pF capacitance of MQ1N8178US/TR impact high-frequency circuit design?
The 4 pF total capacitance of MQ1N8178US/TR minimizes insertion loss and phase distortion in RF paths up to 2 GHz, allowing direct placement on antenna feedlines and high-speed serial links without retuning matching networks. This value is confirmed at 0 V bias and remains stable across temperature, unlike polymer-based TVS alternatives.
MQ1N8178US/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):
- 110V
- Voltage - Breakdown (Min):
- 124V
- Voltage - Clamping (Max) @ Ipp:
- 183V
- Current - Peak Pulse (10/1000µs):
- 820mA
- 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
MQ1N8178US/TR FAQ
1.How can I place an order for MQ1N8178US/TR through Aetrix?
Please submit a Request for Quotation (RFQ) for MQ1N8178US/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 MQ1N8178US/TR reliable?
The price and inventory of MQ1N8178US/TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MQ1N8178US/TR is usually 5 days.
3.What payment methods are accepted for MQ1N8178US/TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MQ1N8178US/TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MQ1N8178US/TR?
MQ1N8178US/TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MQ1N8178US/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 MQ1N8178US/TR?
For technical support, including MQ1N8178US/TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MQ1N8178US/TR requirements.
6.How does Aetrix verify that MQ1N8178US/TR is sourced from the original manufacturer or authorized distributors?
All MQ1N8178US/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 MQ1N8178US/TR meets industry standards.
7.What is the process for return or replacement of MQ1N8178US/TR?
All MQ1N8178US/TR units undergo pre-shipment inspection (PSI). If there is an issue with MQ1N8178US/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 MQ1N8178US/TR part is unused and in its original packaging.
Return procedure for MQ1N8178US/TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MQ1N8178US/TR 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
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…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
