Diodes Incorporated 1N4732A-T

Overview

1N4732A-T from Diodes Incorporated is a 1.0W, 4.7V ±5% Zener diode in DO-41 glass package, designed for voltage regulation and reference applications with 8.0Ω zener impedance at 53mA test current and -0.03 to +0.04%/°C temperature coefficient. It operates across -65°C to +175°C and supports surge current up to 970mA (8.3ms).

For engineers reviewing the 1N4732A-T datasheet, 1N4732A-T pinout, 1N4732A-T application, or 1N4732A-T equivalent, this part serves as a precision low-voltage shunt regulator in power supply feedback loops, overvoltage protection circuits, and analog reference generation where stable 4.7V clamping under varying thermal conditions is required.

Technical Context

This Zener diode functions as a two-terminal shunt voltage regulator, maintaining a nominal 4.7V breakdown voltage at 53mA test current (IZT) with sharp knee characteristics verified by dual-point impedance measurement. Its 8.0Ω dynamic impedance (ZZT) at IZT and 500Ω at knee current (IZK = 1.0mA) ensures stable regulation across load and line variations.

The device uses a glass-passivated DO-41 package with Sn96.5Ag3.5 terminations, rated for 1.0W dissipation at 25°C and derated linearly above 50°C (6.67mW/°C), achieving 175°C/W junction-to-ambient thermal resistance with 9.5mm lead length.

Key Specifications

Pinout & Package

DO-41 glass axial package with cathode band marking; two-terminal device with no internal polarity-sensitive circuitry beyond standard diode junction orientation.

Key Features

Applications

Availability

1N4732A-T is available at Aetrix Electronics and suitable for switch-mode power supplies, overvoltage protection circuits, analog sensor references, and microcontroller reset circuits requiring stable component supply and long-lifecycle support.

Supply support for 1N4732A-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, serving industrial, computing, consumer, and communications markets with high-reliability components.

The 1N47xxA series belongs to Diodes' legacy Zener diode product line, engineered specifically for general-purpose voltage regulation and reference applications where robustness, consistency, and wide temperature operation are critical.

FAQ

What is the maximum continuous power dissipation for 1N4732A-T at 70°C ambient?

At 70°C ambient, the 1N4732A-T is derated to 0.87W. This is calculated from its 1.0W rating at 25°C and 6.67mW/°C derating above 50°C: 1.0W − (6.67mW/°C × 20°C) = 0.867W. Thermal performance assumes 9.5mm lead length per datasheet Note 1.

How does the temperature coefficient affect regulation accuracy over -40°C to +125°C?

With a TC of -0.03 to +0.04%/°C, the 1N4732A-T exhibits a maximum VZ shift of ±6.3mV over a 165°C span (from -40°C to +125°C), resulting in total variation of ±0.13% around 4.7V. This enables stable reference use without active compensation in many industrial applications.

Can 1N4732A-T replace 1N4732A-A in the same PCB footprint?

Yes - both share identical DO-41 glass package dimensions, cathode band marking, and electrical specifications. The "-T" suffix denotes tape-and-reel packaging for automated assembly, while "-A" indicates ammo pack; mechanical fit and function are fully interchangeable.

Is 1N4732A-T suitable for use in automotive applications?

No - although it operates from -65°C to +175°C, the 1N4732A-T is not AEC-Q200 qualified and lacks automotive-specific qualification testing (e.g., vibration, extended temperature cycling, sulfur resistance). Diodes Incorporated lists it as obsolete with no automotive-grade replacement.