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Microchip Technology 1N4148UB
- Part No.:
- 1N4148UB
- Manufacturer:
- Microchip Technology
- Category:
- Single Diodes
- Package:
- 3-SMD, No Lead
- Datasheet:
-
1N4148UB.pdf
- Description:
- SWITCHING DIODE
- Quantity:
- Payment:
- Shipping:
Inventory:5,801
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Product details
Overview
1N4148UB from Microsemi is a ceramic-bodied surface-mount switching diode qualified to MIL-PRF-19500/116 at JAN/JANTX/JANTXV levels, with 75 V working peak reverse voltage, 5 ns reverse recovery time, and 4.0 pF capacitance at 0 V - deployed in high-frequency RS-232 interfaces and Ethernet 10 Base-T data lines.
For engineers reviewing the 1N4148UB datasheet, 1N4148UB pinout, 1N4148UB application, or 1N4148UB equivalent, this military-grade switching diode supports low-profile PCB layouts requiring stable leakage performance (≤25 nA @ 20 V), fast transient response, and thermal robustness up to +200 °C junction temperature.
Technical Context
This 1N4148UB is a unidirectional silicon planar epitaxial switching diode fabricated in a hermetically sealed ceramic UB package with gold-plated nickel terminals. Its design targets high-speed signal routing where low capacitance (4.0 pF @ 0 V) and minimal reverse recovery time (5 ns) are critical for integrity on 10–100 MHz data paths.
The device meets MIL-PRF-19500/116 requirements across JAN, JANTX, and JANTXV reliability levels, with thermal resistance junction-to-solder pad of 120 °C/W and storage temperature range from –65 °C to +200 °C - enabling operation in avionics, ruggedized communications, and space-qualified subsystems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 75 V - maximum continuous reverse voltage before significant leakage or breakdown in normal operation |
| trr | 5 ns - enables clean edge transitions in >20 MHz digital signal routing without tail current distortion |
| C (at 0 V) | 4.0 pF - minimizes capacitive loading on high-speed data lines such as RS-422 or LAN PHY interfaces |
| IR @ 20 V | 25 nA - ensures negligible standby current draw in battery-backed or low-power monitoring circuits |
| TJ Range | –65 °C to +200 °C - supports deployment in extreme environments including engine control units and satellite payload electronics |
| RθJSP | 120 °C/W - allows direct thermal coupling to solder pads for reliable power dissipation without heatsinks |
Pinout & Package
Ceramic surface-mount UB package (2-pin, unidirectional); dimensions: 3.25 mm × 2.74 mm × 1.42 mm (L × W × H), gold-plated nickel terminals, marked with part number and date code.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward current entry point | Connected to source-side of signal path; must be biased positive relative to cathode for conduction |
| Cathode | Forward current exit point | Typically tied to reference plane or return path; polarity marking aligns with cathode band on ceramic body |
Key Features
| Feature | Design Value |
|---|---|
| MIL-PRF-19500/116 qualification | JAN/JANTX/JANTXV screening ensures tested reliability for defense and aerospace deployments |
| Ceramic hermetic packaging | Prevents moisture ingress and parameter drift under thermal cycling or humidity stress |
| Low forward voltage (0.8 V @ 10 mA) | Reduces power loss and self-heating in high-duty-cycle signal clamping applications |
| RoHS-compliant by design | No lead, cadmium, or halogen content - meets IPC-1752A material declaration requirements |
Applications
| RS-232 Interface Protection | Ethernet 10 Base-T Line Clamping |
|---|---|
Use Scenario: Bidirectional ESD and overvoltage protection on serial communication lines between microcontrollers and industrial peripherals. IC Role / Device Role / Timing Role: Signal-level clamping diode placed at transceiver I/O pins to shunt transient energy to ground or VCC rails. Use Value: 5 ns trr prevents signal edge smearing; 25 nA IR avoids DC bias shift in high-impedance receiver inputs. | Use Scenario: Transient suppression on differential pair lanes of legacy Ethernet PHY interfaces operating at 10 Mbps. IC Role / Device Role / Timing Role: Fast-switching clamp limiting line voltage excursions during cable hot-plug or lightning-induced surges. Use Value: 4.0 pF capacitance avoids signal integrity degradation at 10 MHz fundamental frequency; ceramic package withstands reflow and mechanical shock. |
| Avionics Data Bus Isolation | Ruggedized LAN Node Protection |
Use Scenario: Signal conditioning and fault isolation in ARINC 429 or MIL-STD-1553B auxiliary bus nodes exposed to wide ambient temperature swings. IC Role / Device Role / Timing Role: Unidirectional switch isolating logic-level signals while blocking reverse leakage across isolated domains. Use Value: –65 °C to +200 °C TJ range maintains functionality across aircraft cabin-to-engine bay temperature gradients. | Use Scenario: Surge protection on Ethernet ports of outdoor network switches deployed in telecom cabinets or rail signaling systems. IC Role / Device Role / Timing Role: Primary front-end clamp absorbing repetitive 10/1000 µs transients per IEC 61000-4-5 Level 3. Use Value: 2 A non-repetitive surge rating and 120 °C/W RθJSP enable survivability without derating in confined thermal envelopes. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar switching diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4148W | Plastic SOD-123 package; not MIL-qualified; 4.0 pF C @ 0 V; 4 ns trr | Commercial-grade only; unsuitable for extended temperature or radiation-hardened use | Select when cost-sensitive, non-military designs require same electrical specs but relaxed reliability screening |
| 1N4148UR-1 | MELF glass package; DO-213AA; 75 V VRWM; 4 pF C; qualified to MIL-PRF-19500/116 (JANTXV) | Higher vibration resistance than ceramic UB; slightly larger footprint; no tape-and-reel standard option | Choose for mechanically demanding environments where MELF form factor improves board-level shock tolerance |
Compared with 1N4148UB, the 1N4148W offers faster trr but lacks military qualification and thermal range, while the 1N4148UR-1 matches reliability level and key parameters but trades ceramic hermeticity for MELF mechanical resilience - both require layout review due to differing footprints and thermal paths.
Availability
1N4148UB is available at Aetrix Electronics and suitable for RS-232 interface protection, Ethernet 10 Base-T line clamping, and avionics data bus isolation requiring stable component supply across extended temperature and long-lifecycle programs.
Supply support for 1N4148UB 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 analog and mixed-signal ICs, discrete devices, and RF solutions for aerospace, defense, and industrial markets.
The 1N4148UB belongs to Microsemi's military-qualified discrete diode product line, engineered specifically for signal integrity and environmental resilience in mission-critical electronic subsystems.
FAQ
What is the maximum junction temperature rating for the 1N4148UB?
The 1N4148UB has a specified junction and storage temperature range of –65 °C to +200 °C. This rating is validated per MIL-PRF-19500/116 and reflects its ceramic hermetic construction, making it suitable for engine bay electronics and space-qualified payloads where thermal extremes occur. The 1N4148UB maintains parametric stability across this full range when operated within its derated current limits.
Is the 1N4148UB RoHS compliant?
Yes, the 1N4148UB is RoHS compliant by design, containing no lead, cadmium, mercury, hexavalent chromium, polybrominated biphenyls (PBB), or polybrominated diphenyl ethers (PBDE). Compliance is confirmed in Microsemi's T4-LDS-0281-2 datasheet and verified through material declarations aligned with IPC-1752A standards. The 1N4148UB meets EU Directive 2011/65/EU requirements without exemptions.
What does "UB" signify in the 1N4148UB part number?
The "UB" suffix in 1N4148UB denotes Microsemi's ceramic surface-mount package variant conforming to MIL-PRF-19500/116. It distinguishes the device from axial (DO-35), MELF (DO-213AA), and plastic SMD variants. The 1N4148UB uses a two-terminal ceramic body with gold-plated nickel terminations and is marked with polarity and date code - all defined in the official Microsemi nomenclature guide.
How does the reverse recovery time of the 1N4148UB compare to commercial 1N4148 variants?
The 1N4148UB has a reverse recovery time (trr) of 5 ns under standard test conditions (IF = IR = 10 mA, RL = 100 Ω), matching or exceeding most commercial 1N4148 variants. Unlike plastic-packaged versions, this value is guaranteed across –65 °C to +150 °C due to MIL-qualified screening. The 1N4148UB's consistency makes it preferred for timing-critical signal routing where trr variation could induce jitter.
Can the 1N4148UB be used in place of the 1N4148UR-1?
The 1N4148UB and 1N4148UR-1 share identical electrical specifications and MIL-PRF-19500/116 JANTXV qualification, but differ in package: UB is ceramic SMD, UR-1 is MELF glass. They are not pin-compatible - footprint, thermal path, and mounting process differ. Substitution requires PCB redesign. The 1N4148UB offers superior hermeticity; the 1N4148UR-1 provides higher mechanical shock resistance. Both are valid options depending on system-level constraints.
1N4148UB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 3-SMD, No Lead
- Packaging:
- Bulk
- Product Status:
- Active
- Technology:
- Standard
- Voltage - DC Reverse (Vr) (Max):
- 75 V
- Current - Average Rectified (Io):
- 200mA
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 100 mA
- Speed:
- Small Signal =< 200mA (Io), Any Speed
- Reverse Recovery Time (trr):
- 5 ns
- Current - Reverse Leakage @ Vr:
- 500 nA @ 75 V
- Capacitance @ Vr, F:
- 4pF @ 0V, 1MHz
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- UB
- Operating Temperature - Junction:
- -65°C ~ 200°C
1N4148UB FAQ
1.How can I place an order for 1N4148UB through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4148UB 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 1N4148UB reliable?
The price and inventory of 1N4148UB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4148UB is usually 5 days.
3.What payment methods are accepted for 1N4148UB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4148UB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4148UB?
1N4148UB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4148UB 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 1N4148UB?
For technical support, including 1N4148UB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4148UB requirements.
6.How does Aetrix verify that 1N4148UB is sourced from the original manufacturer or authorized distributors?
All 1N4148UB 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 1N4148UB meets industry standards.
7.What is the process for return or replacement of 1N4148UB?
All 1N4148UB units undergo pre-shipment inspection (PSI). If there is an issue with 1N4148UB, 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 1N4148UB part is unused and in its original packaging.
Return procedure for 1N4148UB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4148UB Tags
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1N4448X-TP
Micro Commercial Co
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1N4148WX-TP
Micro Commercial Co
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1N4148TR
onsemi
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MMSD4148T1G
onsemi
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MMBD914LT3G
onsemi
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BAS16HT1G
onsemi
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1N914BWT
onsemi
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BAS21LT1G
onsemi
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LL4148
onsemi
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BAS16LT1G
onsemi
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MMSD914T1G
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BAV21W-7-F
Diodes Incorporated
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