1N4740A – VISHAY

Overview

The VISHAY 1N4740A is a 1-watt, 10-volt Zener diode designed for precise voltage regulation in discrete circuits. Its primary function is to maintain a stable output voltage across its terminals when subjected to reverse breakdown, making it ideal for reference voltage generation and overvoltage protection. A critical design consideration when employing this component is its Zzt (Zener Impedance), which at 7 Ohms, directly impacts the transient response and ripple rejection capabilities of the regulated supply; a lower impedance is generally preferred for superior dynamic performance, though this often involves a trade-off with power dissipation.

Key Features

• Zener Voltage (Vz): 10 V
• Power Dissipation (Pmax): 1 W
• Tolerance: ±5%
• Maximum Zener Impedance (Zzt): 7 Ohms
• Reverse Leakage Current: 10 µA @ 7.6 V
• Operating Temperature Range: -65°C to 200°C
• Package: DO-41 (Axial)

Applications

The component is engineered for deployment in systems requiring high reliability and performance under specific operating conditions. It provides functional stability across the stated design envelope.

• Precision voltage reference in linear power supplies.
• Overvoltage clamping for sensitive analog signal paths.
• Voltage stabilization in battery-powered portable equipment.
• Shunt regulation for bias voltage in audio amplifier stages.