Diodes Incorporated 1N4750A-T

Overview

1N4750A-T from Diodes Incorporated is a 1.0 W, 27 V ±5% Zener diode in DO-41 glass package, designed for voltage regulation and reference applications with 35 Ω zener impedance at 9.5 mA test current and 0.25 µA reverse leakage at 20.6 V. It operates across –65°C to +175°C and is RoHS-compliant with Sn96.5Ag3.5 terminations.

For engineers reviewing the 1N4750A-T datasheet, 1N4750A-T pinout, 1N4750A-T application, or 1N4750A-T equivalent, key selection criteria include nominal zener voltage (27 V), power dissipation (1.0 W), zener impedance (35 Ω), temperature coefficient (+0.06 to +0.095 %/°C), and DO-41 mechanical compatibility in legacy power supply and analog reference designs.

Technical Context

This device functions as a precision voltage reference by maintaining a stable 27 V breakdown under reverse bias, with sharp knee characteristics verified via dual-point Zener impedance measurement per JEDEC standards. Its thermal resistance of 175 °C/W (junction-to-ambient) requires lead length control (9.5 mm) above 50°C for full power rating.

The diode exhibits a positive temperature coefficient (+0.06 to +0.095 %/°C), indicating increasing V_Z with temperature - critical for temperature-compensated references. Reverse leakage remains ≤5.0 µA at rated VR (20.6 V), supporting low-power standby regulation.

Key Specifications

Pinout & Package

DO-41 glass axial package with two terminals: anode and cathode. Cathode identified by a distinct color band. Leads are Sn96.5Ag3.5 plated and solderable per MIL-STD-202, Method 208. Mechanical dimensions: overall length 26.0 mm max, body diameter 0.86–2.60 mm, weight ≈0.35 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DFLZ27-7, the 1N4750A-T offers proven axial-leaded reliability in serviceable or high-vibration environments; compared with 1N4750A-A, it provides identical performance with optimized pick-and-place compatibility for SMT lines.

Availability

1N4750A-T is available at Aetrix Electronics and suitable for industrial power supplies, analog instrumentation, overvoltage protection circuits, and legacy control system repairs requiring stable component supply and long-term obsolescence mitigation.

Supply support for 1N4750A-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 semiconductor company specializing in discrete, analog, and mixed-signal devices, with design and manufacturing operations across Asia and the Americas.

The 1N47xx series belongs to Diodes' legacy Zener diode product line, engineered for general-purpose voltage regulation and reference in cost-sensitive, high-reliability industrial and consumer power systems.

FAQ

What is the maximum continuous reverse voltage that can be safely applied to the 1N4750A-T?

The 1N4750A-T is rated for a nominal Zener voltage of 27 V at 9.5 mA test current. Its absolute maximum reverse voltage is defined by its 20.6 V rated voltage (V_R) - applying ≥20.6 V will produce ≤5.0 µA leakage, while stable regulation begins near 27 V. Exceeding 27 V continuously risks thermal runaway unless current is strictly limited by external series resistance.

How does the +0.06 to +0.095 %/°C temperature coefficient affect circuit performance?

This positive coefficient means the Zener voltage increases by 0.06–0.095% per °C rise in junction temperature. For example, a 50°C rise adds ~0.0825%/°C × 50°C × 27 V ≈ 110 mV to V_Z. Designers must account for this drift in precision references or use complementary negative-coefficient devices for compensation.

Can the 1N4750A-T replace the 1N4750A-A in existing assemblies?

Yes - the 1N4750A-T and 1N4750A-A share identical electrical specifications, DO-41 package dimensions, and marking. The only difference is packaging format: tape-and-reel (–T) versus ammo pack (–A). No circuit or layout changes are needed; both are fully interchangeable at the board level.

Why is the 1N4750A-T marked "Not Recommended for New Design"?

Diodes Incorporated designates the 1N47xx series as "Not Recommended for New Design" due to the availability of more efficient, smaller-footprint alternatives like the DFLZ series. This reflects strategic portfolio focus-not reliability concerns. The 1N4750A-T remains fully qualified, in production, and supported for repair, legacy, and cost-driven applications.