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Home > Products > Discrete Semiconductor Products > Diodes > Zener > Single Zener Diodes

Microchip Technology 1N5221BUR-1

Name: 1N5221BUR-1
Brand: Microchip Technology
SKU: 1N5221BUR-1
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: 1N5221BUR-1

Manufacturer:: Microchip Technology

Category:: Single Zener Diodes

Package:: DO-213AA

Datasheet:: 1N5221BUR-1.pdf

Description:: DIODE ZENER 2.4V 500MW DO213AA

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Product details

Overview

1N5221BUR-1 from Microsemi is a 2.4 V, ±5% tolerance, 500 mW surface-mount Zener diode in DO-213AA (SOD-80) MELF package, designed for precision voltage regulation in low-power analog circuits, reference supplies, and overvoltage protection. It delivers 20 mA test current, 30 Ω dynamic impedance at I_ZT, and operates across –65 °C to +175 °C junction temperature.

For engineers reviewing the 1N5221BUR-1 datasheet, 1N5221BUR-1 pinout, 1N5221BUR-1 application, or 1N5221BUR-1 equivalent, key selection criteria include Zener voltage accuracy, thermal resistance (R_θJA = 250 °C/W), low leakage (<100 µA @ 0.95 V), minimal capacitance, and hermetically sealed metallurgically bonded construction for reliability in harsh environments.

Technical Context

The 1N5221BUR-1 functions as a two-terminal, reverse-biased silicon Zener regulator with sharp breakdown knee (I_ZK = 0.25 mA) and stable regulation over wide current (0.25–20 mA) and temperature ranges. Its metallurgically bonded glass package ensures low thermal resistance (R_θJEC = 100 °C/W) and high reliability under thermal cycling.

It exhibits a negative temperature coefficient of –0.085 %/°C, enabling predictable drift compensation in reference designs. The device is RoHS-compliant (e3 suffix option), non-ESD-sensitive per MIL-STD-750 Method 1020, and radiation-hardened per MicroNote 050 - making it suitable for aerospace and industrial control applications requiring long-term stability.

Key Specifications

Parameter	Value and Actual Design Meaning
Zener Voltage V_Z	2.4 V ±5% at 20 mA - defines precise regulation point for low-voltage references and biasing.
Power Dissipation P_D	0.5 W - supports continuous operation up to 20 mA at 25 °C ambient with derating above 50 °C.
Zener Impedance Z_ZT	30 Ω at I_ZT = 20 mA - ensures low output impedance for stable regulation under load variation.
Reverse Leakage I_R	<100 µA at 0.95 V - minimizes standby current in battery-powered or high-impedance sensing circuits.
Junction Temp Range	–65 °C to +175 °C - enables deployment in extended-temperature industrial, automotive, and aerospace systems.
Thermal Resistance R_θJA	250 °C/W on FR4 (1 oz Cu) - dictates PCB layout requirements for thermal management and power handling.

Pinout & Package

DO-213AA (SOD-80 / MLL34) metallurgically bonded glass MELF package: hermetically sealed, cathode band marked, end-cap terminals only - no leads. Dimensions: Ø1.6–1.7 mm × L3.3–3.7 mm. Weight: 0.04 g.

Pin/Terminal	Circuit Role	Design Meaning
Cathode (banded end)	Zener anode connection in reverse-bias configuration	Connected to higher potential node; regulates voltage when reverse-biased - polarity critical for correct operation.
Anode (unbanded end)	Zener cathode connection in reverse-bias configuration	Connected to lower potential (e.g., ground or return path); completes regulation loop with cathode at regulated voltage.

Key Features

Feature	Design Value
Metallurgical bond construction	Enables robust thermal transfer and mechanical integrity in high-reliability MELF packages - eliminates wire bonds prone to fatigue.
Hermetically sealed glass case	Prevents moisture ingress and contamination - maintains long-term Zener voltage stability and leakage performance in humid or corrosive environments.
Negative tempco (–0.085 %/°C)	Allows predictable, compensatable drift in precision references - simplifies temperature compensation circuitry versus positive-coefficient devices.
Low capacitance (typ. <2 pF)	Minimizes signal coupling and high-frequency loading - preserves bandwidth in RF detector, timing, and fast-switching feedback paths.

Applications

Low-Voltage Reference Supply	Overvoltage Clamp Protection
Use Scenario: Providing stable 2.4 V bias for op-amp input stages, ADC reference dividers, or sensor excitation in portable instrumentation. IC Role / Device Role / Timing Role: Two-terminal shunt voltage reference regulating node voltage against supply variation and load changes. Use Value: Delivers ±5% initial accuracy and <30 Ω dynamic impedance to maintain <10 mV regulation error across 1–20 mA load range.	Use Scenario: Clamping transient surges on 3.3 V logic rails or analog sensor inputs exposed to ESD or inductive kickback. IC Role / Device Role / Timing Role: Passive shunt clamp absorbing excess energy by entering controlled reverse breakdown before downstream IC damage. Use Value: Responds within nanoseconds with <100 µA leakage at 0.95 V, limiting clamped voltage to ≤2.6 V during transients.
Temperature-Stable Bias Network	Aerospace Power Monitor Reference
Use Scenario: Generating temperature-compensated bias currents in precision amplifiers or oscillators operating from –40 °C to +125 °C. IC Role / Device Role / Timing Role: Zener element in tempco-matched resistor networks to cancel thermal drift of active devices. Use Value: Predictable –0.085 %/°C coefficient enables direct matching with NTC resistors or complementary transistor V_BE drift.	Use Scenario: Serving as primary voltage reference in satellite power distribution units monitoring 28 V bus health via scaled-down sense lines. IC Role / Device Role / Timing Role: Radiation-hardened, MIL-PRF-19500 up-screenable shunt reference ensuring calibration integrity in space-grade telemetry. Use Value: Inherent radiation hardness per MicroNote 050 and hermetic sealing guarantee no parametric shift after 100 krad(Si) exposure.

Low-Voltage Reference Supply

Overvoltage Clamp Protection

Use Scenario: Providing stable 2.4 V bias for op-amp input stages, ADC reference dividers, or sensor excitation in portable instrumentation.

IC Role / Device Role / Timing Role: Two-terminal shunt voltage reference regulating node voltage against supply variation and load changes.

Use Value: Delivers ±5% initial accuracy and <30 Ω dynamic impedance to maintain <10 mV regulation error across 1–20 mA load range.

Use Scenario: Clamping transient surges on 3.3 V logic rails or analog sensor inputs exposed to ESD or inductive kickback.

IC Role / Device Role / Timing Role: Passive shunt clamp absorbing excess energy by entering controlled reverse breakdown before downstream IC damage.

Use Value: Responds within nanoseconds with <100 µA leakage at 0.95 V, limiting clamped voltage to ≤2.6 V during transients.

Temperature-Stable Bias Network

Aerospace Power Monitor Reference

Use Scenario: Generating temperature-compensated bias currents in precision amplifiers or oscillators operating from –40 °C to +125 °C.

IC Role / Device Role / Timing Role: Zener element in tempco-matched resistor networks to cancel thermal drift of active devices.

Use Value: Predictable –0.085 %/°C coefficient enables direct matching with NTC resistors or complementary transistor V_BE drift.

Use Scenario: Serving as primary voltage reference in satellite power distribution units monitoring 28 V bus health via scaled-down sense lines.

IC Role / Device Role / Timing Role: Radiation-hardened, MIL-PRF-19500 up-screenable shunt reference ensuring calibration integrity in space-grade telemetry.

Use Value: Inherent radiation hardness per MicroNote 050 and hermetic sealing guarantee no parametric shift after 100 krad(Si) exposure.

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener regulation applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
1N5221B-1	Same electrical specs but in axial DO-35 (JEDEC DO-204AH) package - no surface-mount footprint.	Requires through-hole PCB assembly; unsuitable for automated SMT lines or space-constrained layouts.	Select when legacy board compatibility or manual prototyping outweighs SMT efficiency.
BZX55C2V4	2.4 V ±5%, 500 mW, DO-35 package - same Zener voltage and tolerance, but higher Z_ZT (60 Ω) and wider tempco (±0.05 %/°C).	Limited to commercial-grade use; not radiation-hardened or MIL-qualified - excludes aerospace/military deployments.	Choose for cost-sensitive consumer electronics where radiation hardness and extended temp range are unnecessary.

Compared with 1N5221B-1 and BZX55C2V4, the 1N5221BUR-1 uniquely combines SMT MELF packaging, hermetic metallurgical bonding, radiation hardness, and tight –0.085 %/°C tempco - making it the only option qualified for high-reliability, thermally demanding, and space-grade applications requiring long-term parametric stability.

Availability

1N5221BUR-1 is available at Aetrix Electronics and suitable for low-power voltage reference, overvoltage protection, and precision bias network applications requiring stable component supply, consistent parametric performance, and long-lifecycle availability.

Supply support for 1N5221BUR-1 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, mixed-signal, and radiation-hardened components for aerospace, defense, and industrial markets.

The 1N5221BUR-1 belongs to Microsemi's legacy 1N52xxUR-1 series of metallurgically bonded Zener regulators - engineered specifically for applications demanding hermetic sealing, extended temperature operation, and MIL-PRF-19500 qualification readiness.

FAQ

What is the Zener voltage and tolerance of the 1N5221BUR-1?

The 1N5221BUR-1 has a nominal Zener voltage of 2.4 V with a tolerance of ±5% at 20 mA test current (I_ZT). This value is guaranteed per the "B" suffix in the part number and confirmed in the Electrical Characteristics table on page 3 of the T4-LDS-0232-1 datasheet. The 1N5221BUR-1 maintains this regulation point across its specified operating temperature and current range.

What package type does the 1N5221BUR-1 use, and is it RoHS compliant?

The 1N5221BUR-1 uses the DO-213AA (SOD-80 or MLL34) metallurgically bonded glass MELF package. RoHS-compliant versions are available with the "e3" suffix (e.g., 1N5221BUR-1e3), but only for commercial-grade units - the base 1N5221BUR-1 may be non-RoHS unless explicitly ordered with e3. Plating is annealed matte-tin for solderability per MIL-STD-750.

What is the maximum power dissipation and thermal resistance of the 1N5221BUR-1?

The 1N5221BUR-1 has a steady-state power dissipation rating of 0.5 W at end cap temperature <125 °C or ambient <50 °C on FR4. Its thermal resistance junction-to-ambient (R_θJA) is 250 °C/W under standard mounting conditions (1 oz Cu, recommended footprint), and junction-to-end-cap (R_θJEC) is 100 °C/W - critical for thermal design validation in the 1N5221BUR-1 application.

Does the 1N5221BUR-1 have radiation hardness, and is it ESD sensitive?

Yes, the 1N5221BUR-1 is inherently radiation-hardened per Microsemi MicroNote 050, and it is non-sensitive to ESD per MIL-STD-750 Method 1020. These attributes are intrinsic to its metallurgically bonded glass construction and are documented in the Applications/Benefits section of the T4-LDS-0232-1 datasheet - key differentiators for the 1N5221BUR-1 in mission-critical systems.

What is the temperature coefficient of the 1N5221BUR-1, and how does it affect regulation?

The 1N5221BUR-1 has a temperature coefficient (αV_Z) of –0.085 %/°C, meaning its Zener voltage decreases predictably with rising temperature. This negative coefficient allows designers to compensate for thermal drift in precision references - a verified characteristic confirmed in Note 3 on page 4 of the 1N5221BUR-1 datasheet and essential for stable 1N5221BUR-1 performance across –65 °C to +175 °C.

1N5221BUR-1 Specifications

Product attributes: Attribute value

Manufacturer:: Microchip Technology

Series:: -

Package/Case:: DO-213AA

Packaging:: Bulk

Product Status:: Active

Voltage - Zener (Nom) (Vz):: 2.4 V

Tolerance:: ±5%

Power - Max:: 500 mW

Impedance (Max) (Zzt):: 30 Ohms

Current - Reverse Leakage @ Vr:: 100 µA @ 1 V

Voltage - Forward (Vf) (Max) @ If:: 1.1 V @ 200 mA

Operating Temperature:: -65°C ~ 175°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: DO-213AA

1N5221BUR-1 FAQ

1.How can I place an order for 1N5221BUR-1 through Aetrix?

Please submit a Request for Quotation (RFQ) for 1N5221BUR-1 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 1N5221BUR-1 reliable?

The price and inventory of 1N5221BUR-1 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5221BUR-1 is usually 5 days.

3.What payment methods are accepted for 1N5221BUR-1?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5221BUR-1 transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for 1N5221BUR-1?

1N5221BUR-1 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 1N5221BUR-1 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 1N5221BUR-1?

For technical support, including 1N5221BUR-1 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5221BUR-1 requirements.

6.How does Aetrix verify that 1N5221BUR-1 is sourced from the original manufacturer or authorized distributors?

All 1N5221BUR-1 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 1N5221BUR-1 meets industry standards.

7.What is the process for return or replacement of 1N5221BUR-1?

All 1N5221BUR-1 units undergo pre-shipment inspection (PSI). If there is an issue with 1N5221BUR-1, 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 1N5221BUR-1 part is unused and in its original packaging.

Return procedure for 1N5221BUR-1:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

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