My Inquiry
My Account
Microchip Technology 1N3644
- Part No.:
- 1N3644
- Manufacturer:
- Microchip Technology
- Category:
- Single Diodes
- Package:
- S, Axial
- Datasheet:
-
1N3644.pdf
- Description:
- DIODE GEN PURP S AXIAL
- Quantity:
- Payment:
- Shipping:
Inventory:6,237
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
1N3644 from Microsemi is a military-qualified, voidless hermetically sealed high-voltage standard recovery rectifier diode rated for 1500 V working peak reverse voltage (VRWM), 0.25 A average forward current at 55 °C, and 1050 V reverse voltage (VR). It features triple-layer passivation, low reverse leakage (≤5 µA at VRWM), and operates from –65 °C to +175 °C. It is used in radar transmitters, X-ray power supplies, and high-reliability voltage multiplier circuits.
For engineers reviewing the 1N3644 datasheet, 1N3644 pinout, 1N3644 application, or 1N3644 equivalent, key selection criteria include its MIL-PRF-19500/279 JAN/JANTX qualification, hermetic glass S-package construction, thermal resistance of 38 °C/W, and verified performance under high-temperature, high-voltage stress conditions.
Technical Context
The 1N3644 is a silicon planar junction standard recovery rectifier with a hard-glass hermetic S-package and tungsten slugs for thermal management. Its 1500 V VRWM and 1050 V VR are defined per MIL-PRF-19500/279, with breakdown voltage ≥1800 V at 1 mA and forward voltage ≤5.0 V at 250 mA.
It delivers 14 A non-repetitive surge current (IZSM) at 8.3 ms, maintains ≤5 µA reverse leakage up to 125 °C, and exhibits absolute high-voltage stability across its –65 °C to +175 °C junction temperature range. Its triple-layer passivation ensures robustness in radiation-hardened environments per MicroNote 050.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 1500 V - Maximum continuous peak reverse voltage usable across full operating temperature range. |
| VR | 1050 V - DC-rated reverse blocking voltage without AC component; defines safe steady-state operation limit. |
| IO @ 55 °C | 0.25 A - Average rectified forward current capability at ambient 55 °C; derates to 0.10 A at 100 °C. |
| VF @ 250 mA | ≤5.0 V - Forward voltage drop at rated test current; impacts conduction loss and thermal design margin. |
| IR @ VRWM | ≤5 µA @ 25 °C - Reverse leakage current at max working voltage; critical for high-impedance, low-power-loss circuits. |
| TJ Range | –65 °C to +175 °C - Junction temperature limits enabling use in aerospace, defense, and industrial harsh environments. |
| RθJL | 38 °C/W - Thermal resistance from junction to lead (3/8″ length); determines heatsinking requirements for power dissipation. |
Pinout & Package
Hermetically sealed voidless hard-glass S-package with tungsten slugs; cathode indicated by band; terminals are tin/lead or RoHS-compliant matte tin over copper; weight ≈400 mg.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward current entry point | Connected to input side of rectification path; must withstand surge current and thermal cycling. |
| Cathode | Forward current exit / reverse blocking terminal | Banded end; carries full reverse voltage; requires clean PCB layout to prevent creepage failure at >1 kV. |
Key Features
| Feature | Design Value |
|---|---|
| Voidless hermetic glass seal | Eliminates internal moisture and contaminants, ensuring long-term reliability in vacuum and high-humidity military environments. |
| Triple-layer passivation | Provides enhanced surface stability against ion migration and surface leakage under high electric field stress. |
| JAN/JANTX qualification | Fully qualified per MIL-PRF-19500/279 - includes screening, lot traceability, and extended temperature testing for mission-critical systems. |
| Lowest reverse leakage | ≤5 µA at VRWM and 25 °C - enables stable biasing in high-impedance detector and multiplier circuits. |
| Radiation hardness | Inherently radiation-tolerant per Microsemi MicroNote 050 - suitable for space-qualified and nuclear instrumentation applications. |
Applications
| Radar Transmitter Power Supplies | X-Ray Generator Voltage Multipliers |
|---|---|
Use Scenario: High-voltage DC generation for magnetron and klystron anode supplies in pulsed radar systems. IC Role / Device Role / Timing Role: High-voltage standard recovery rectifier in Cockcroft-Walton ladder networks. Use Value: 1500 V VRWM and 14 A surge rating sustain repetitive pulse loads while maintaining low leakage at elevated temperatures. |
Use Scenario: Cascaded voltage multiplication in medical and industrial X-ray tube power supplies. IC Role / Device Role / Timing Role: Series-connected rectifier in multi-stage doubler circuits requiring stable reverse blocking. Use Value: Hermetic glass package prevents internal arcing at >10 kV cumulative stack voltages; triple passivation suppresses surface flashover. |
| Military Communication Transmitters | High-Reliability Industrial Power Supplies |
Use Scenario: Final-stage rectification in HF/VHF amplifier plate supplies for secure comms equipment. IC Role / Device Role / Timing Role: Catch diode and HV filter feed in Class AB/C RF power supply rails. Use Value: –65 °C to +175 °C operation supports wide environmental deployment; JAN-level screening ensures zero infant mortality. |
Use Scenario: Input rectification in ruggedized AC/DC converters for oilfield telemetry and avionics ground support. IC Role / Device Role / Timing Role: Primary HV rectifier in transformer-isolated front-end stages. Use Value: 38 °C/W RθJL enables conduction-cooled mounting on chassis; low thermal resistance reduces derating penalties. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-voltage rectifier applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N3645 | Higher VRWM (2000 V) and VR (1400 V); same S-package, JAN/JANTX qualification, and thermal specs. | Used where system-level reverse voltage margin exceeds 1500 V but layout and thermal constraints match 1N3644. | Select when higher voltage headroom is required without changing footprint or thermal interface. |
| 1N4254 | Same VRWM (1500 V) and VR (1050 V); lower forward voltage (≤3.5 V @ 100 mA); commercial-grade only; no MIL qualification. | Suitable for cost-sensitive industrial power supplies where MIL screening and radiation tolerance are not required. | Choose for non-military designs needing identical voltage ratings but relaxed reliability and compliance requirements. |
Compared with 1N3645 and 1N4254, the 1N3644 uniquely balances MIL-PRF-19500/279 qualification, 1500 V capability, and proven field reliability in life-critical HV systems-making it the default choice when both voltage rating and assured quality are mandatory.
Availability
1N3644 is available at Aetrix Electronics and suitable for radar transmitter power supplies, X-ray generator voltage multipliers, and military communication transmitters requiring stable component supply, long-term obsolescence mitigation, and traceable MIL-spec sourcing.
Supply support for 1N3644 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 military-qualified analog and mixed-signal components.
The 1N3644 belongs to Microsemi's legacy high-voltage rectifier family designed specifically for defense, aerospace, and industrial systems demanding guaranteed performance under extreme voltage, temperature, and reliability stress.
FAQ
What is the maximum working peak reverse voltage (VRWM) for the 1N3644?
The 1N3644 has a VRWM of 1500 V, defined per MIL-PRF-19500/279 as the maximum peak reverse voltage sustainable across its full operating temperature range (–65 °C to +175 °C). This rating is validated through standardized high-potential and temperature-cycle testing, and is distinct from its 1050 V DC reverse voltage (VR) rating.
Is the 1N3644 qualified to military specifications?
Yes, the 1N3644 is qualified to MIL-PRF-19500/279 at both JAN and JANTX reliability levels. This includes rigorous screening for parameter limits, burn-in, temperature cycling, and lot traceability. Only the 1N3644 through 1N3647 series in this family carry this qualification - commercial variants lack these tests.
What package type does the 1N3644 use, and how is polarity marked?
The 1N3644 uses a hermetically sealed voidless hard-glass S-package with tungsten slugs for thermal conduction. Polarity is marked by a visible cathode band on the glass body; the banded end is the cathode terminal, and the unmarked end is the anode. Lead finish is tin/lead (Pb-free options available for commercial grade only).
What is the forward voltage drop of the 1N3644 at rated current?
The 1N3644 exhibits a maximum forward voltage (VF) of 5.0 V at 250 mA and 25 °C, as specified in the Electrical Characteristics table. This value increases with temperature and current; designers must account for it in thermal modeling, especially given its 1.5 W steady-state power dissipation limit and 38 °C/W junction-to-lead thermal resistance.
Can the 1N3644 be used in radiation-intensive environments?
Yes, the 1N3644 is inherently radiation-hardened per Microsemi MicroNote 050. Its planar junction structure, triple-layer passivation, and hermetic glass packaging provide tolerance to total ionizing dose (TID) and displacement damage, making it suitable for satellite power systems, nuclear instrumentation, and high-altitude avionics where radiation exposure is expected.
1N3644 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- S, Axial
- Packaging:
- Bulk
- Product Status:
- Active
- Technology:
- Standard
- Voltage - DC Reverse (Vr) (Max):
- -
- Current - Average Rectified (Io):
- -
- Voltage - Forward (Vf) (Max) @ If:
- 5 V @ 250 mA
- Speed:
- Standard Recovery >500ns, > 200mA (Io)
- Reverse Recovery Time (trr):
- -
- Current - Reverse Leakage @ Vr:
- -
- Capacitance @ Vr, F:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- S, Axial
- Operating Temperature - Junction:
- -65°C ~ 175°C
1N3644 FAQ
1.How can I place an order for 1N3644 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N3644 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 1N3644 reliable?
The price and inventory of 1N3644 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N3644 is usually 5 days.
3.What payment methods are accepted for 1N3644?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N3644 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N3644?
1N3644 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N3644 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 1N3644?
For technical support, including 1N3644 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N3644 requirements.
6.How does Aetrix verify that 1N3644 is sourced from the original manufacturer or authorized distributors?
All 1N3644 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 1N3644 meets industry standards.
7.What is the process for return or replacement of 1N3644?
All 1N3644 units undergo pre-shipment inspection (PSI). If there is an issue with 1N3644, 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 1N3644 part is unused and in its original packaging.
Return procedure for 1N3644:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N3644 Tags
-
1N4448X-TP
Micro Commercial Co
-
1N4148WX-TP
Micro Commercial Co
-
1N4148TR
onsemi
-
MMSD4148T1G
onsemi
-
MMBD914LT3G
onsemi
-
BAS16HT1G
onsemi
-
1N914BWT
onsemi
-
BAS21LT1G
onsemi
-
LL4148
onsemi
-
BAS16LT1G
onsemi
-
MMSD914T1G
onsemi
-
BAV21W-7-F
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…
