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Microchip Technology 1N5229B
- Part No.:
- 1N5229B
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-204AH, DO-35, Axial
- Datasheet:
-
1N5229B.pdf
- Description:
- DIODE ZENER 4.3V 500MW DO204AH
- Quantity:
- Payment:
- Shipping:
Inventory:9,970
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Product details
Overview
1N5229B from Microsemi is a 500 mW, 4.3 V ±5% glass axial-lead Zener diode in DO-35 (DO-204AH) package, rated for 20 mA test current, 22 Ω dynamic impedance at IZT, and -65°C to +175°C operating temperature range. It provides stable voltage regulation in low-power reference and protection circuits.
For engineers reviewing the 1N5229B datasheet, 1N5229B pinout, 1N5229B application, or 1N5229B equivalent, key selection factors include its tight 5% tolerance, low 22 Ω Zener impedance at 20 mA, minimal temperature coefficient of ±0.055 %/°C, and robust thermal performance up to 175°C in axial-leaded through-hole mounting.
Technical Context
This discrete Zener diode operates in reverse breakdown to maintain a stable 4.3 V reference across a broad current range (0.25 mA to 20 mA), with specified dynamic impedance measured at both IZT (20 mA) and IZK (0.25 mA). Its DO-35 glass package ensures hermetic sealing and radiation hardness per MicroNote 050.
The device exhibits low capacitance (typical <2 pF at VR = 1 V), nonsensitive ESD behavior (MIL-STD-750 Method 1020), and thermal resistance of 250 °C/W junction-to-lead at 3/8" lead length - enabling reliable operation in high-temperature industrial and aerospace environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Nominal Zener Voltage | 4.3 V ±5% at 20 mA - defines precise regulation point for low-voltage reference design |
| Power Dissipation | 500 mW at 25°C - sets maximum continuous power handling before derating |
| Zener Impedance | 22 Ω at IZT = 20 mA - indicates low AC impedance for stable regulation under varying load |
| Reverse Current | 5.0 μA max at VR = 1.0 V - ensures low leakage in standby or precision biasing |
| Temperature Coefficient | ±0.055 %/°C - enables predictable voltage drift over -65°C to +175°C operating range |
| Forward Voltage | ≤1.5 V at 200 mA - supports use as clamp or rectifier in dual-polarity circuits |
| Package | DO-35 (DO-204AH) glass axial-leaded - provides hermetic seal, MIL-compatibility, and through-hole reliability |
Pinout & Package
DO-35 (DO-204AH) hermetically sealed glass axial-leaded package with cathode band marking; leads are tin-lead or RoHS-compliant matte-tin plated, solderable per MIL-STD-750 Method 2026.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Non-banded end | Connected to lower potential during Zener operation; used for forward conduction or clamping |
| Cathode | Banded end | Connected to higher potential during Zener regulation; defines polarity for voltage reference |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered Zener | Complies with JEDEC 1N5221–1N5281B standard for interchangeability and testing consistency |
| 5% voltage tolerance (B suffix) | Guarantees VZ within ±5% at 20 mA - tighter than generic 10% (A) or 20% (no suffix) variants |
| Radiation-hardened construction | Inherently radiation hard per MicroNote 050 - suitable for space-qualified and high-reliability systems |
| ESD-insensitive | Passes MIL-STD-750 Method 1020 - eliminates need for external ESD protection in handling and assembly |
| Low capacitance | Typical <2 pF at 1 V reverse bias - preserves signal integrity in RF and high-speed timing applications |
Applications
| Overvoltage Protection Circuit | Low-Power Voltage Reference |
|---|---|
Use Scenario: Clamping transient spikes on 5 V logic supply rails in industrial PLC I/O modules. IC Role / Device Role: Shunt regulator that conducts excess current when voltage exceeds 4.3 V, protecting downstream CMOS inputs. Use Value: 22 Ω Zener impedance ensures fast response to transients while maintaining stable clamping threshold across temperature. | Use Scenario: Providing stable 4.3 V bias for op-amp comparators in battery-powered sensor nodes. IC Role / Device Role: Precision voltage reference source drawing only 20 mA, minimizing quiescent current drain. Use Value: ±5% tolerance and ±0.055 %/°C tempco enable accurate trip-point setting over extended temperature ranges. |
| Temperature-Stable Bias Network | Aerospace Power Monitor |
Use Scenario: Generating temperature-compensated bias for transistor amplifiers in avionics RF front-ends. IC Role / Device Role: Zener element in compensated voltage divider network with NTC thermistor. Use Value: Predictable ±0.055 %/°C drift allows precise cancellation of amplifier gain drift up to 175°C ambient. | Use Scenario: Monitoring regulated bus voltage in satellite power distribution units with radiation exposure. IC Role / Device Role: Radiation-hardened shunt reference in fault-detection comparator circuitry. Use Value: Inherent radiation hardness per MicroNote 050 eliminates need for shielding or redundancy in LEO missions. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4733A (ON Semiconductor) | 5.1 V nominal, 1 W rating, DO-41 package, ±5% tolerance, 17 Ω Zz at 49 mA | Higher power and voltage; requires PCB layout change due to larger DO-41 footprint | Select when 5.1 V reference and >500 mW dissipation are required; not drop-in for 4.3 V or DO-35 constraints |
| MMBZ5229BS (Diodes Inc.) | 4.3 V, ±5%, SOT-23 surface-mount, 225 mW, 22 Ω Zz at 20 mA | Same VZ and Zz but lower power and SMT-only; no axial-leaded option | Choose for space-constrained PCBs where reflow compatibility and smaller size outweigh through-hole reliability needs |
Compared with 1N4733A and MMBZ5229BS, the 1N5229B offers unique value in hermetically sealed DO-35 packaging, full -65°C to +175°C operation, and radiation hardness - making it irreplaceable in high-reliability, high-temperature, or radiation-exposed designs where SMT or higher-voltage alternatives fall short.
Availability
1N5229B is available at Aetrix Electronics and suitable for overvoltage protection, low-power voltage reference, temperature-stable bias networks, and aerospace power monitoring requiring stable component supply across extended temperature and radiation environments.
Supply support for 1N5229B 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 (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability, radiation-hardened, and high-temperature analog and mixed-signal components.
The 1N5229B belongs to Microsemi's legacy 1N52xxB Zener series designed for precision voltage regulation in military, aerospace, and industrial systems demanding long-term stability and extreme environmental resilience.
FAQ
What is the nominal Zener voltage and tolerance of the 1N5229B?
The 1N5229B has a nominal Zener voltage of 4.3 V with a guaranteed tolerance of ±5% at 20 mA test current (IZT), as confirmed by Microsemi's official electrical characteristics table. This B-suffix designation ensures tighter regulation than A-suffix (±10%) or unsuffixed (±20%) variants in the same family. The 1N5229B maintains this specification across its full operating temperature range.
What package type and marking does the 1N5229B use?
The 1N5229B uses the DO-35 (DO-204AH) hermetically sealed glass axial-leaded package with cathode indicated by a single band on the banded end. The device is marked with its full part number "1N5229B" on the glass body. Lead finish is tin-lead or RoHS-compliant matte-tin, solderable per MIL-STD-750 Method 2026.
What is the Zener impedance of the 1N5229B and why does it matter?
The 1N5229B has a maximum Zener impedance (ZZT) of 22 Ω at IZT = 20 mA, measured per JEDEC-standard AC superposition method. This low dynamic impedance ensures minimal output voltage variation under changing load currents - critical for stable reference generation in precision analog circuits and fast transient suppression in protection applications.
Can the 1N5229B operate reliably at high temperatures?
Yes, the 1N5229B is rated for continuous operation from -65°C to +175°C, with thermal resistance of 250 °C/W junction-to-lead at 3/8" lead length. Its glass DO-35 package and internal construction support full-spec performance across this range, validated per Microsemi's derating curve (Figure 1) and referenced in MicroNote 050 for high-temperature reliability.
Is the 1N5229B radiation-hardened and ESD-safe?
Yes, the 1N5229B is inherently radiation-hardened per MicroNote 050 and ESD-insensitive per MIL-STD-750 Method 1020. These attributes are built into its DO-35 glass construction and process - no additional screening or qualification is needed. This makes the 1N5229B suitable for space, nuclear, and high-reliability defense applications without supplemental hardening.
1N5229B Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-204AH, DO-35, Axial
- Packaging:
- Bulk
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 4.3 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- 22 Ohms
- Current - Reverse Leakage @ Vr:
- 5 µA @ 1 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.5 V @ 200 mA
- Operating Temperature:
- -65°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-204AH (DO-35)
1N5229B FAQ
1.How can I place an order for 1N5229B through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N5229B 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 1N5229B reliable?
The price and inventory of 1N5229B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5229B is usually 5 days.
3.What payment methods are accepted for 1N5229B?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5229B transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N5229B?
1N5229B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N5229B 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 1N5229B?
For technical support, including 1N5229B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5229B requirements.
6.How does Aetrix verify that 1N5229B is sourced from the original manufacturer or authorized distributors?
All 1N5229B 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 1N5229B meets industry standards.
7.What is the process for return or replacement of 1N5229B?
All 1N5229B units undergo pre-shipment inspection (PSI). If there is an issue with 1N5229B, 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 1N5229B part is unused and in its original packaging.
Return procedure for 1N5229B:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N5229B Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
-
MMSZ5231B-7-F
Diodes Incorporated
-
BZT52C15-7-F
Diodes Incorporated
-
BZX84C3V3LT1G
onsemi
-
MMSZ5245BS-7-F
Diodes Incorporated
-
MMSZ4682T1G
onsemi
-
BZT52C15S-7-F
Diodes Incorporated
-
MM5Z5V1ST1G
onsemi
-
SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
Diodes Incorporated
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