Diodes Incorporated 1N5241B-T

Overview

1N5241B-T from Diodes Incorporated is a 11 V, ±5% tolerance, 500 mW surface-mount Zener diode in a hermetic DO-35 glass package, rated for operation from –65°C to +175°C, with 22 Ω zener impedance at 20 mA test current and +0.076 %/°C temperature coefficient-used for precision voltage reference and overvoltage protection in low-power analog circuits.

For engineers reviewing the 1N5241B-T datasheet, 1N5241B-T pinout, 1N5241B-T application, or 1N5241B-T equivalent, this part serves as a legacy discrete voltage regulation device requiring attention to thermal derating above 75°C, RoHS-compliant lead finish (Sn96.5Ag3.5), cathode band polarity marking, and obsolescence status relative to MMSZ52xxB replacements.

Technical Context

This Zener diode operates in reverse breakdown to maintain stable 11 V across its terminals under controlled current conditions. Its 22 Ω dynamic impedance at I_ZT = 20 mA and low 0.25 mA knee current (I_ZK) enable predictable regulation in low-current bias networks and feedback paths.

The DO-35 glass package provides hermetic sealing and high stability, with thermal resistance of 300 °C/W junction-to-ambient (at TL ≤ 75°C, 9.5 mm lead length). Its ±5% V_Z tolerance and +0.076 %/°C temperature coefficient define accuracy limits in temperature-varying environments.

Key Specifications

Pinout & Package

Package: DO-35 glass axial package with hermetic seal, cathode band marking, Sn96.5Ag3.5 solderable leads, and 0.13 g mass. Dimensions: A ≤ 25.4 mm, B ≤ 4.0 mm, C ≤ 0.6 mm, D ≤ 2.0 mm.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMSZ5241B and 1N4741A, the 1N5241B-T offers identical voltage specification and temperature range in a hermetic DO-35 package, but its 500 mW rating and 22 Ω impedance position it between the SMT-optimized MMSZ series and the higher-power 1N47xx family-making it suitable for space-constrained, high-reliability analog references where leaded assembly remains viable.

Availability

1N5241B-T is available at Aetrix Electronics and suitable for industrial sensor signal conditioning, low-power microcontroller reset circuits, and automotive body control modules requiring stable component supply despite obsolescence status.

Supply support for 1N5241B-T 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design and manufacturing operations across Asia and the Americas.

The 1N52xxB series belongs to Diodes' legacy Zener diode product line, engineered for precision voltage regulation in cost-sensitive, high-reliability analog systems where hermetic packaging and wide temperature operation are critical.

FAQ

Is the 1N5241B-T still in active production?

No-the 1N5241B-T is officially obsolete per Diodes Incorporated's DS18006 Rev. 19 (September 2019). It has been superseded by the MMSZ5241B SOD-123 surface-mount variant. Aetrix Electronics maintains limited legacy stock for design continuity and repair programs, with full traceability and date-code documentation.

What is the maximum allowable junction temperature for continuous operation?

The absolute maximum junction temperature is +175°C, but continuous operation requires thermal management to keep lead temperature ≤75°C at 9.5 mm from case. At ambient 25°C, this implies a maximum power dissipation of 500 mW only if R_θJA ≤300°C/W is maintained-derating begins linearly above 75°C lead temperature.

Can the 1N5241B-T be used in place of the 1N4741A?

Electrically, yes-for 11 V reference applications-but mechanical and thermal differences matter. The 1N5241B-T has 500 mW power rating vs. 1 W for the 1N4741A, and uses DO-35 vs. DO-41 packaging. Substitution requires verifying thermal margin and board layout compatibility; it is not a drop-in replacement under high-power or high-surge conditions.

Does the 1N5241B-T meet automotive AEC-Q200 requirements?

No-the 1N5241B-T is not AEC-Q200 qualified. While it operates from –65°C to +175°C and is used in some automotive BCMs, Diodes Incorporated does not list it in their AEC-Q200 stress-tested portfolio. For automotive production, the MMSZ5241B (AEC-Q200 Grade 1) or 1N4741A (unqualified but widely deployed) are more common alternatives.