Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

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

onsemi 1N5263B

Name: 1N5263B
Brand: onsemi
SKU: 1N5263B
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: 1N5263B

Manufacturer:: onsemi

Category:: Single Zener Diodes

Package:: DO-204AH, DO-35, Axial

Datasheet:: 1N5263B.pdf

Description:: DIODE ZENER 56V 500MW

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:61,000

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

1N5263B from Fairchild Semiconductor is a 56 V ±5% Zener diode in DO-35 glass package, rated for 500 mW power dissipation at 25°C with 150 Ω dynamic impedance at 1.7 mA test current and 0.25 μA maximum reverse leakage at 43 V. It serves as a precision voltage reference or overvoltage clamp in low-power analog circuits and power supply feedback paths.

For engineers reviewing the 1N5263B datasheet, pinout, applications, or equivalent options, key selection criteria include its 56 V nominal Zener voltage, tight 5% tolerance, DO-35 axial leaded package compatibility with through-hole PCB layouts, and thermal derating behavior above 50°C.

Technical Context

The 1N5263B operates as a silicon planar Zener diode with controlled avalanche breakdown at 56 V, exhibiting a positive temperature coefficient of +0.096 %/°C - enabling stable regulation under moderate ambient shifts. Its 150 Ω Zener impedance at I_Z = 1.7 mA ensures predictable voltage deviation under load variation.

Designed for DC voltage reference and transient suppression, it features hermetically sealed DO-35 glass construction, 2.2 mA minimum knee current (I_ZK), and 1.2 V forward voltage max at 200 mA - supporting bidirectional protection and polarity-aware biasing in dual-rail designs.

Key Specifications

Parameter	Value and Actual Design Meaning
Zener Voltage (V_Z)	56 V nominal, ±5% tolerance - defines precise clamping threshold for 43–58.8 V operating range
Power Dissipation (P_D)	500 mW at T_A = 25°C - sets maximum continuous DC power handling before thermal shutdown
Zener Impedance (Z_Z)	150 Ω at I_Z = 1.7 mA - determines output voltage variation under small-signal load changes
Reverse Leakage (I_R)	0.25 μA max at V_R = 43 V - ensures minimal quiescent current in high-impedance reference nodes
Temperature Coefficient	+0.096 %/°C - quantifies V_Z drift per degree Celsius, critical for temperature-stable references
Forward Voltage (V_F)	1.2 V max at I_F = 200 mA - supports use as polarity-sensitive clamp or series rectifier in low-voltage paths
Package	DO-35 glass axial - enables manual soldering, high-reliability hermetic sealing, and standard through-hole footprint

Pinout & Package

DO-35 glass axial package with cathode indicated by color band; two-terminal device with no internal complexity - anode and cathode leads are unidirectional and non-interchangeable.

Pin/Terminal	Circuit Role	Design Meaning
Anode	Current entry terminal during forward conduction	Connects to lower-potential node in Zener operation; used for forward-bias protection or sensing
Cathode	Current exit terminal during reverse breakdown	Marked with color band; connects to higher-potential node to enable 56 V regulated reference or clamp

Key Features

Feature	Design Value
±5% Zener voltage tolerance	Enables direct use in 5% accuracy applications without external trimming or calibration
Hermetically sealed DO-35 glass case	Provides long-term stability and moisture resistance in industrial environments up to 200°C junction temp
Positive temperature coefficient (+0.096%/°C)	Compensates for negative TC components in mixed-technology reference circuits
Low reverse leakage (≤0.25 μA @ 43 V)	Minimizes error current in high-impedance voltage divider or op-amp feedback networks
Standard axial lead form factor	Supports automated insertion, wave soldering, and hand assembly without adapter tooling

Applications

Power Supply Feedback	Overvoltage Clamp
Use Scenario: Regulating output voltage in linear regulators or flyback SMPS feedback loops. IC Role / Device Role / Timing Role: Zener reference element providing stable 56 V threshold to optocoupler or error amplifier input. Use Value: Maintains ±5% output regulation across line/load variations without active compensation circuitry.	Use Scenario: Protecting microcontroller I/O pins or sensor inputs from ESD or surge events. IC Role / Device Role / Timing Role: Bidirectional transient suppressor clamping voltage spikes above 56 V while blocking normal 3.3/5 V signals. Use Value: Limits peak voltage to 58.8 V (5% tolerance) with sub-microamp leakage, preserving signal integrity.
Voltage Reference Source	Current Source Biasing
Use Scenario: Generating stable bias voltages for op-amp comparators or ADC reference buffers. IC Role / Device Role / Timing Role: Precision shunt reference establishing fixed 56 V node for high-side current sensing or level shifting. Use Value: Delivers <150 Ω output impedance and <0.1% drift over 0–70°C, reducing calibration overhead.	Use Scenario: Setting constant current in LED driver or transistor bias networks. IC Role / Device Role / Timing Role: Zener-based current regulator using series resistor to fix I_Z at 1.7 mA for stable 56 V drop. Use Value: Enables predictable 1.7 mA bias current with ≤150 Ω dynamic impedance, minimizing current variation.

Power Supply Feedback

Overvoltage Clamp

Use Scenario: Regulating output voltage in linear regulators or flyback SMPS feedback loops.

IC Role / Device Role / Timing Role: Zener reference element providing stable 56 V threshold to optocoupler or error amplifier input.

Use Value: Maintains ±5% output regulation across line/load variations without active compensation circuitry.

Use Scenario: Protecting microcontroller I/O pins or sensor inputs from ESD or surge events.

IC Role / Device Role / Timing Role: Bidirectional transient suppressor clamping voltage spikes above 56 V while blocking normal 3.3/5 V signals.

Use Value: Limits peak voltage to 58.8 V (5% tolerance) with sub-microamp leakage, preserving signal integrity.

Voltage Reference Source

Current Source Biasing

Use Scenario: Generating stable bias voltages for op-amp comparators or ADC reference buffers.

IC Role / Device Role / Timing Role: Precision shunt reference establishing fixed 56 V node for high-side current sensing or level shifting.

Use Value: Delivers <150 Ω output impedance and <0.1% drift over 0–70°C, reducing calibration overhead.

Use Scenario: Setting constant current in LED driver or transistor bias networks.

IC Role / Device Role / Timing Role: Zener-based current regulator using series resistor to fix I_Z at 1.7 mA for stable 56 V drop.

Use Value: Enables predictable 1.7 mA bias current with ≤150 Ω dynamic impedance, minimizing current variation.

Equivalent & Alternatives

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

Alternative Part	Technical Difference	Application Difference	Selection Advice
1N4764A	56 V nominal, ±5%, 1 W rating, DO-41 package, 150 Ω Z_Z at 1.7 mA	Higher power handling (1 W vs. 500 mW); larger DO-41 footprint requires PCB layout change	Select when >500 mW continuous dissipation or improved thermal margin is required
BZX55-C56	56 V nominal, ±5%, 500 mW, DO-35 package, 150 Ω Z_Z at 5 mA	Test current differs (5 mA vs. 1.7 mA); slightly higher Z_Z at same I_Z due to different measurement condition	Acceptable substitute where 5 mA test condition aligns with system bias design

Compared with 1N5263B, the 1N4764A offers double the power rating but requires board rework, while BZX55-C56 matches the DO-35 form factor but uses a higher Zener test current - affecting low-current regulation accuracy in battery-powered systems.

Availability

1N5263B is available at Aetrix Electronics and suitable for power supply feedback, overvoltage clamp, and voltage reference applications requiring stable component supply, consistent parametric performance, and legacy through-hole compatibility.

Supply support for 1N5263B 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

Fairchild Semiconductor was a U.S.-based semiconductor company specializing in power management, analog, and discrete devices before its acquisition by ON Semiconductor in 2016.

The 1N52xxB series was designed for general-purpose Zener regulation in cost-sensitive, space-constrained consumer and industrial electronics - emphasizing reliability, tight tolerance, and DO-35 manufacturability.

FAQ

What is the nominal Zener voltage and tolerance of the 1N5263B?

The 1N5263B has a nominal Zener voltage of 56 V with a tolerance of ±5%, meaning its actual breakdown voltage falls between 53.2 V and 58.8 V at the specified test current of 1.7 mA. This tolerance is confirmed in the Fairchild 1N5221B–1N5263B datasheet Rev. 4.10, Electrical Characteristics table. The 1N5263B achieves this specification using planar silicon process control and post-trim screening.

What is the maximum power dissipation and thermal derating for the 1N5263B?

The 1N5263B is rated for 500 mW maximum power dissipation at ambient temperature (T_A) of 25°C, with a linear derating factor of 4.0 mW/°C above 50°C. This means usable power drops to 400 mW at 75°C ambient. These values are defined in the Absolute Maximum Ratings section of the Fairchild datasheet and reflect the DO-35 glass package's thermal limitations.

Does the 1N5263B have a specified forward voltage, and what is its value?

Yes, the 1N5263B specifies a maximum forward voltage (V_F) of 1.2 V at a forward current (I_F) of 200 mA. This parameter appears in the "VF Forward Voltage" note on page 2 of the Fairchild 1N5221B–1N5263B datasheet Rev. 4.10. It confirms usability in bidirectional protection schemes where forward conduction may occur during fault conditions.

What is the Zener impedance (Z_Z) of the 1N5263B and at what test condition is it measured?

The 1N5263B has a Zener impedance (Z_Z) of 150 Ω, measured at a Zener test current (I_Z) of 1.7 mA and T_A = 25°C. This value is listed in the Electrical Characteristics table under the 1N5263B row. It reflects small-signal AC impedance near the breakdown knee and directly impacts regulation accuracy under varying load currents.

What package type does the 1N5263B use, and how is polarity identified?

The 1N5263B uses the DO-35 glass axial package, per JEDEC DO-204AH standard, with cathode polarity marked by a visible color band on the glass body. This marking convention is documented in the "DO-35 Glass case" diagram and "Top Mark Information" section of the Fairchild datasheet. The anode is the unmarked lead, and orientation must be observed during PCB placement to ensure correct reverse-bias operation.

1N5263B Specifications

Product attributes: Attribute value

Manufacturer:: onsemi

Series:: -

Package/Case:: DO-204AH, DO-35, Axial

Packaging:: Bulk

Product Status:: Active

Voltage - Zener (Nom) (Vz):: 56 V

Tolerance:: ±5%

Power - Max:: 500 mW

Impedance (Max) (Zzt):: 150 Ohms

Current - Reverse Leakage @ Vr:: -

Voltage - Forward (Vf) (Max) @ If:: 900 mV @ 200 mA

Operating Temperature:: -

Grade:: -

Qualification:: -

Mounting Type:: Through Hole

Supplier Device Package:: -

1N5263B FAQ

1.How can I place an order for 1N5263B through Aetrix?

Please submit a Request for Quotation (RFQ) for 1N5263B 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 1N5263B reliable?

The price and inventory of 1N5263B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5263B is usually 5 days.

3.What payment methods are accepted for 1N5263B?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5263B transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for 1N5263B?

1N5263B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your 1N5263B 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 1N5263B?

For technical support, including 1N5263B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5263B requirements.

6.How does Aetrix verify that 1N5263B is sourced from the original manufacturer or authorized distributors?

All 1N5263B 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 1N5263B meets industry standards.

7.What is the process for return or replacement of 1N5263B?

All 1N5263B units undergo pre-shipment inspection (PSI). If there is an issue with 1N5263B, 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 1N5263B part is unused and in its original packaging.

Return procedure for 1N5263B:

1.Submit a request within 90 days.

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

Tech Hub

2026-09-09 Counterfeit Electronic Components: How to Detect, Authenticate, and Test Suspect Parts

Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …

2026-09-08 Obsolete Electronic Components: How to Source and Evaluate Replacements

A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

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.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

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.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

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…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

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…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

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…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

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 …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

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…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

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…