onsemi 1N5226B_S00Z

Overview

1N5226B_S00Z from ON Semiconductor is a 3.3 V, ±5% tolerance, 500 mW silicon Zener diode in DO-35 glass package, designed for precision voltage regulation and reference applications in low-power analog circuits, power supply feedback loops, and overvoltage protection. It delivers 28 Ω dynamic impedance at 20 mA test current with -0.07 %/°C temperature coefficient.

For engineers reviewing the 1N5226B_S00Z datasheet, pinout, applications, or equivalent options, this page provides verified electrical parameters, thermal derating behavior, cathode identification, and direct replacement options for legacy Fairchild-designated designs requiring stable 3.3 V reference performance.

Technical Context

This device operates as a two-terminal voltage reference using avalanche breakdown in a planar-diffused silicon junction. Its 3.3 V nominal Zener voltage is specified at I_Z = 20 mA with tight 5% tolerance and measured under controlled thermal equilibrium (T_L = 30°C ± 1°C, 3/8″ lead length).

The 1N5226B_S00Z exhibits a negative temperature coefficient (-0.07 %/°C), indicating decreasing V_Z with rising temperature - critical for biasing stability in temperature-sensitive analog stages. Its 500 mW power rating is derated linearly above 50°C at 4.0 mW/°C to maintain safe junction operation within -65°C to +200°C range.

Key Specifications

Pinout & Package

DO-35 hermetically sealed glass package (JEDEC DO-204AH), 0.533 mm diameter body, 4.56 mm overall length, 0.137 g weight. Cathode identified by single color band near one end.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5226B_S00Z, 1N4728A offers higher power margin but requires layout change and introduces positive tempco drift; BZX55C3V3 matches all key specs while reducing leakage by 250×, making it ideal for energy-constrained designs without altering PCB footprint.

Availability

1N5226B_S00Z is available at Aetrix Electronics and suitable for power supply feedback, overvoltage protection, reference voltage source, and analog sensor biasing applications requiring stable component supply across industrial, automotive, and consumer electronics programs.

Supply support for 1N5226B_S00Z 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient power, analog, sensor, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The 1N52xxB series belongs to ON Semiconductor's legacy Zener diode product line, engineered for general-purpose voltage regulation and reference functions in cost-sensitive, low-power analog circuits.

FAQ

What is the exact Zener voltage tolerance and test condition for 1N5226B_S00Z?

The 1N5226B_S00Z has a ±5% tolerance on its nominal 3.3 V Zener voltage, verified at I_Z = 20 mA under thermal equilibrium conditions (lead temperature T_L = 30°C ± 1°C, 3/8″ lead length). This ensures repeatable regulation performance in production assemblies where thermal management is controlled.

Does 1N5226B_S00Z have a cathode marking, and how is it identified?

Yes, the 1N5226B_S00Z uses a single color band on the DO-35 glass body to denote the cathode terminal. This band is positioned adjacent to the cathode end and must be oriented toward the higher-potential node in Zener operation. The anode is the unmarked end.

Can 1N5226B_S00Z replace older Fairchild 1N5226B parts without redesign?

Yes - 1N5226B_S00Z is the ON Semiconductor–branded continuation of the Fairchild 1N5226B, maintaining identical electrical specifications, DO-35 package dimensions, pinout, and marking convention. No PCB or schematic changes are needed for drop-in replacement.

What is the maximum allowable ambient temperature before derating applies to 1N5226B_S00Z?

The 1N5226B_S00Z operates up to +200°C junction temperature, but its full 500 mW power rating is only valid at T_A = 25°C. Derating begins at +50°C ambient, reducing power by 4.0 mW per °C rise - meaning maximum dissipation drops to 400 mW at +75°C ambient.

How does the -0.07 %/°C temperature coefficient affect circuit performance in a 0–70°C range?

Over a 70°C span, the 1N5226B_S00Z exhibits approximately -0.49 % total V_Z drift (−0.07 %/°C × 70°C), translating to −16.2 mV shift from 3.3 V. This is acceptable for non-critical references but should be compensated in precision instrumentation using matched resistors or active correction.