Microchip Technology 1N5233A

Overview

1N5233A from Microsemi is a 6.0 V, ±10% tolerance, 500 mW glass axial-lead Zener diode in DO-35 (DO-204AH) package, rated for 20 mA test current, 7.0 Ω dynamic impedance at IZT, and -65°C to +175°C operating temperature - used for precision voltage reference and low-power regulation in analog sensor signal conditioning circuits.

For engineers reviewing the 1N5233A datasheet, 1N5233A pinout, 1N5233A application, or 1N5233A equivalent, this page delivers verified electrical specs, thermal derating behavior, Zener voltage temperature coefficient (+0.038 %/°C), cathode band polarity marking, and RoHS-compliant e3 variant availability.

Technical Context

The 1N5233A operates as a two-terminal voltage reference device with reverse-biased breakdown governed by controlled avalanche and Zener mechanisms. Its 6.0 V nominal Zener voltage is specified at 20 mA test current (IZT), with dynamic impedance measured at both IZT and 0.25 mA (IZK) to ensure stable knee characteristics.

Thermal performance is defined by 250 °C/W junction-to-lead resistance at 10 mm lead length and 310 °C/W junction-to-ambient on FR4 board; forward voltage is capped at 1.5 V @ 200 mA, and it exhibits minimal capacitance per Figure 2 - enabling use in low-noise biasing and feedback networks.

Key Specifications

Pinout & Package

DO-35 (DO-204AH) hermetically sealed glass axial-leaded package with cathode indicated by colored band; leads are tin-lead or RoHS-compliant matte-tin plated, solderable per MIL-STD-750 Method 2026.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N5233A, the 1N5233B improves initial accuracy without changing thermal or dynamic behavior, while MMBZ5233BS trades power rating and impedance for miniaturization - making 1N5233A optimal for through-hole, high-stability, and high-temp applications.

Availability

1N5233A is available at Aetrix Electronics and suitable for instrumentation reference, power supply feedback, and sensor bias networks requiring stable component supply across extended temperature ranges and long-lifecycle programs.

Supply support for 1N5233A 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-voltage analog components for aerospace, defense, and industrial markets.

The 1N52xx series was designed as a JEDEC-standardized family of general-purpose Zener diodes delivering consistent regulation performance across 2.4–200 V with military-grade screening options and extended temperature capability.

FAQ

What is the nominal Zener voltage and tolerance of the 1N5233A?

The 1N5233A has a nominal Zener voltage of 6.0 V with a ±10% tolerance, as designated by the "A" suffix per Microsemi's documentation. This means the actual breakdown voltage falls between 5.4 V and 6.6 V at 20 mA test current and 25°C ambient. The 1N5233A is not rated for tighter tolerances - those require the "B" (±5%), "C" (±2%), or "D" (±1%) suffix variants.

Does the 1N5233A have a specified Zener impedance, and what does it mean for circuit design?

Yes, the 1N5233A has a maximum Zener impedance (ZZT) of 7.0 Ω at 20 mA test current. This value reflects the incremental resistance near the breakdown knee and directly impacts regulation stability: lower ZZT means less output voltage variation under changing load current. In practice, this allows the 1N5233A to maintain tighter voltage control in feedback loops and reference buffers without additional filtering.

What is the temperature coefficient of the 1N5233A, and how does it affect long-term accuracy?

The 1N5233A has a Zener voltage temperature coefficient (αVZ) of +0.038 %/°C, meaning its regulated voltage increases by approximately 2.28 mV per °C rise above 25°C. This positive drift is typical for Zeners above 5 V and must be accounted for in wide-temperature applications - for example, over a -40°C to +85°C range, the 1N5233A's VZ shifts by roughly ±480 mV, which influences total system error budgets.

Can the 1N5233A be used in surface-mount designs?

No - the 1N5233A is exclusively packaged in the axial-leaded DO-35 (DO-204AH) glass case and is not compatible with SMT assembly. For surface-mount equivalents, Microsemi offers the MLL5233B in DO-213AA (MELF) package, and third-party alternatives like the MMBZ5233BS in SOT-23 exist - but these differ in power rating, impedance, and thermal behavior, so direct substitution requires revalidation.

Is the 1N5233A RoHS compliant, and how is compliance indicated?

Yes, RoHS-compliant versions of the 1N5233A are available with the "e3" suffix (e.g., 1N5233Ae3), indicating annealed matte-tin plating per J-STD-609. The base 1N5233A may use traditional tin-lead plating unless otherwise specified; therefore, designers requiring RoHS conformance must explicitly order the e3 variant to ensure compliance with EU Directive 2011/65/EU and related environmental standards.