Diodes Incorporated 1N4754A-T

Overview

1N4754A-T from Diodes Incorporated is a 1.0 W, 39 V ±5% Zener diode in DO-41 glass package, designed for precision voltage regulation and reference applications with 60 Ω zener impedance at 6.5 mA test current and -65°C to +175°C operating temperature range. It delivers stable clamping in power supply feedback loops and overvoltage protection circuits.

For engineers reviewing the 1N4754A-T datasheet, 1N4754A-T pinout, 1N4754A-T application, or 1N4754A-T equivalent, key selection criteria include nominal Zener voltage (39 V), power dissipation (1.0 W), zener impedance (60 Ω), reverse leakage (≤5 µA at 29.7 V), and thermal resistance (175 °C/W).

Technical Context

This discrete Zener diode operates in reverse breakdown mode to maintain a stable reference voltage across its terminals under varying load and temperature conditions. Its 39 V nominal Zener voltage is specified at 6.5 mA test current (IZT), with a sharp knee ensured by dual-point impedance measurement per JEDEC standards.

The device exhibits a positive temperature coefficient (+0.06 to +0.095 %/°C) and low capacitance (~15 pF typical), making it suitable for DC voltage reference and transient suppression where minimal parasitic effects are required. Thermal performance is defined for lead length = 9.5 mm at TL = 50°C.

Key Specifications

Pinout & Package

Package: DO-41 glass axial package with cathode band marking; case material rated UL 94V-0; weight ≈ 0.35 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 1N4754A-T, DFLZ39-7-F offers superior manufacturability and surge robustness in SMT layouts, while 1N4754A-A provides identical performance in legacy through-hole production-both preserve the 39 V reference function but address distinct assembly and lifecycle requirements.

Availability

1N4754A-T is available at Aetrix Electronics and suitable for switch-mode power supplies, overvoltage protection circuits, analog reference generation, and microcontroller reset supervision requiring stable component supply and long-term obsolescence management.

Supply support for 1N4754A-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, specializing in high-reliability, industry-standard components for power management, signal integrity, and protection.

The 1N47xxA series belongs to Diodes' legacy Zener diode product line, engineered for general-purpose voltage regulation and reference applications across consumer, industrial, and computing markets.

FAQ

What is the maximum steady-state power dissipation for 1N4754A-T at 70°C ambient?

At 70°C ambient, the 1N4754A-T must be derated from its 1.0 W rating at 25°C using the 6.67 mW/°C slope above 50°C. This yields 1.0 W − (6.67 mW/°C × 20°C) = 866 mW maximum continuous power dissipation. Derating assumes leads held at 50°C with 9.5 mm length from case per datasheet Note 1.

Is 1N4754A-T suitable for use in automotive under-hood applications?

No-while the 1N4754A-T operates from −65°C to +175°C, it is not AEC-Q200 qualified and lacks automotive-specific screening, traceability, or PPAP documentation. For under-hood use, Diodes' AEC-Q200-certified DFLZ series or automotive-grade Zeners should be selected instead.

How does the 39 V Zener voltage relate to the 29.7 V reverse test voltage (VR)?

The 29.7 V reverse test voltage (VR) is 76% of the nominal 39 V Zener voltage and is used to measure reverse leakage current (IR ≤ 5 µA). This standardized test point ensures consistent leakage evaluation across the 1N47xxA family and reflects operation well below breakdown, confirming low off-state conduction.

Can 1N4754A-T replace 1N4753A or 1N4755A in existing designs?

Yes-1N4754A-T is electrically interchangeable with adjacent parts in the series (e.g., 1N4753A = 36 V, 1N4755A = 43 V) if the circuit tolerates ±3 V shift in regulation point. However, zener impedance increases from 50 Ω (1N4753A) to 60 Ω (1N4754A-T) to 70 Ω (1N4755A), affecting regulation stiffness under dynamic loads.