Diodes Incorporated 1N4756A-T

Overview

1N4756A-T from Diodes Incorporated is a 1.0 W, 47 V ±5% Zener diode in DO-41 glass package, rated for 5.5 mA test current, 80 Ω dynamic impedance at IZT, and 35.8 V minimum knee voltage at 0.25 mA. It provides precision voltage regulation in low-power linear power supplies and reference circuits.

For engineers reviewing the 1N4756A-T datasheet, 1N4756A-T pinout (cathode band polarity), 1N4756A-T application in voltage reference and overvoltage clamping, or 1N4756A-T equivalent for 47 V Zener regulation, this page delivers verified electrical specs, thermal derating behavior, DO-41 mechanical dimensions, and RoHS-compliant solderability data per MIL-STD-202.

Technical Context

This device operates as a two-terminal silicon Zener diode with sharp reverse breakdown at nominal 47 V, designed for stable DC voltage reference and shunt regulation. Its 80 Ω Zener impedance at 5.5 mA and 1500 Ω at 0.25 mA reflect controlled knee characteristics suitable for low-current biasing and sensing applications.

Thermal performance is defined by 175 °C/W junction-to-ambient resistance at 25 °C ambient, with linear derating of 6.67 mW/°C above 50 °C when leads are held at 50 °C with 9.5 mm length. Forward voltage is specified at 1.2 V @ 200 mA, confirming standard silicon PN junction behavior.

Key Specifications

Pinout & Package

DO-41 glass axial package: hermetically sealed glass body, 26.0 mm max overall length (A), 4.10 mm max diameter (B), 0.86 mm max lead diameter (C), 2.60 mm max lead spacing (D). Cathode identified by single black band.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DFLZ47-700, 1N4756A-T offers lower Z_ZT and proven through-hole reliability; versus 1N4756A-A, it provides identical performance with optimized reel-based handling for high-volume SMT lines.

Availability

1N4756A-T is available at Aetrix Electronics and suitable for linear power supply references, overvoltage clamp circuits, temperature-compensated reference stacks, and low-power bias networks requiring stable component supply and long-term obsolescence management.

Supply support for 1N4756A-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 1N47xxA series belongs to Diodes' legacy Zener diode product line, engineered for cost-effective, high-reliability voltage regulation in industrial, consumer, and computing power systems.

FAQ

What is the maximum surge current rating for 1N4756A-T?

The 1N4756A-T is rated for 95 A maximum non-repetitive peak forward surge current (I_FSM) under 8.3 ms half-sine wave conditions. This value is derived from its 1.0 W power rating and thermal mass, and applies only to short-duration transients-not continuous operation. Exceeding this limit risks irreversible junction damage.

How does thermal derating affect power dissipation above 50°C?

Above 50°C ambient, 1N4756A-T power dissipation must be reduced linearly at 6.67 mW/°C. At 75°C ambient, maximum allowable P_d drops to 833 mW. This derating assumes leads are maintained at 50°C with 9.5 mm length from case-critical for accurate thermal modeling in enclosure-constrained designs.

Is 1N4756A-T suitable for use in automotive applications?

1N4756A-T is not AEC-Q200 qualified and lacks automotive-grade screening or extended temperature validation beyond its –65°C to +175°C storage range. While its operating temperature range overlaps automotive under-hood environments, Diodes Incorporated does not recommend or guarantee performance in safety-critical or mission-critical automotive subsystems without additional qualification testing.

What is the significance of the "-T" suffix in 1N4756A-T?

The "-T" suffix denotes tape-and-reel packaging: 5,000 units per reel in DO-41 carrier tape, compatible with automated SMT placement equipment. It shares identical electrical, thermal, and mechanical specifications with the "-A" (ammo pack) variant-only packaging format differs, with no impact on circuit performance or reliability.